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Introduction: Amyloidosis is a disorder where misfolded proteins get deposited in different tissues. The most common of them is immunoglobulin light chain (AL) deposition, otherwise known as AL amyloidosis. Cardiac involvement generally correlates with poor prognosis, and treatment options are limited if presented late. Novel disease-modifying agents are being studied in on-going trials to optimize treatment strategy. This review aims to summarize the updates on upcoming treatment options for AL amyloidosis, particularly involving the heart. Methodology: We performed a comprehensive literature search on PubMed, clinicaltrials.gov, and Cochrane databases (last updated on May 20, 2020). We used MeSH terms along with their keywords and combined their results. The literature search generated a total of 652 references. Two independent reviewers screened the articles and shortlisted 21 clinical trials that were included in our final review. Results: Monoclonal antibodies (daratumumab, isatuximab, elotuzumab and birtamimab) are being studied as monotherapy and combinations in relapsed/refractory (RR) AL amyloidosis. Despite good data on efficacy and safety, Daratumumab has not been approved yet in this category for advanced cardiac amyloidosis patients. Isatuximab showed the overall hematological response (HR) of 56% in phase I trial in a combination regimen and is now being evaluated as monotherapy in phase II. In a recent phase III trial of RR AL amyloidosis patients, the median progression-free survival was assessed over 24.5 months. It was increased from 14.9 months (lenalidomide and dexamethasone alone) to 19.4 months (elotuzumab, lenalidomide, and dexamethasone). Immunomodulators (lenalidomide, pomalidomide, thalidomide) are well studied for safety in other malignancies. Lenalidomide in various combinations has shown hematological response of greater than 60% in AL amyloidosis. Similarly, pomalidomide has shown an overall hematological response of 48-50% in two different early phase trials. Moreover, thalidomide was associated with significant toxicity in phase I/II trials and was discontinued. Second-generation proteasome inhibitors (ixazomib and carfilzomib) were assessed in RR cases of AL amyloidosis. Ixazomib achieved a hematological response of 52%. However, carfilzomib has been associated with cardiovascular toxicity and a higher risk of hospitalization in phase I trials, making it unsuitable. Venetoclax has shown encouraging results in multiple myeloma, particularly in t(11:14). 50% of AL amyloidosis cases have t(11:14) in whom venetoclax can be beneficial. A trial [NCT03000660] was suspended halfway citing clinical hold from regulatory authorities. Alkylating agents, mainly bendamustine, are currently under study after it showed a survival advantage in heavily pretreated cases [NCT01222260]. Underexplored venues: Small interfering RNAs (siRNAs) have a favorable response and excellent toxicity profile in AL amyloidosis. Issues regarding half-life and delivery systems have limited their use. CAEL-101, a novel chimeric fibril-reactive monoclonal antibody (gG1κ 11-1F4), tolerated well with improved organ function in AL amyloidosis in an early phase trial where it improved global longitudinal strain from baseline -9.58 to -13.39. SB203580 + rapamycin combination works in synergy with the former inhibiting the p38 MAPK pathway markedly reducing the toxicity of light chain immunoglobulins on cardiac myocytes and the latter restoring the SB203580-induced autophagic dysregulation. Epigallocatechin-3-gallate (EGCG) was well tolerated and found non-inferior to standard chemotherapy in a small phase II trial [NCT01511263]. Serum amyloid P (SAP) is a chaperone protein in amyloid fibril formation. Anti-SAP antibodies have shown promising results with safe toxicity profile in phase I trial [NCT01777243] in non-cardiac involved patients. However, another trial in cardiac involved cases was terminated due to significant toxicity. Table 1 Conclusion: Numerous drugs with novel mechanisms of actions are being studied, and results so far offer hope for improving the therapy & outcomes, especially in patients with cardiac involvement. The drug combination regimens lead to slow down the disease progression by interfering at multiple steps in the cascade of light chain synthesis, secretion, deposition, and organ clearance. Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.: Honoraria, Research Funding, Speakers Bureau.

Introduction . In multiple myeloma (MM), the presence of translocation t(4;14) and/or 17p deletion, found in around 10 to 15% of the patients, is considered as high-risk feature associated with adverse survival. Despite recent advances in the treatment of MM, t(4;14) and del(17p) are still associated with poor outcome. The aim of this study was to analyze the trends of survival in patients with newly diagnosed MM harboring t(4;14) and or 17p deletion over the past two decades. Methods . Patients from five French centers with newly-diagnosed MM from 2001 to 2019 and displaying del(17p) and/or t(4;14) were retrospectively included. Cytogenetics abnormalities were detected by interphase fluorescence in situ hybridization (FISH) and del(17p) positivity cut-off was 30%. New agents were defined as: pomalidomide, carfilzomib, ixazomib and anti-CD38 monoclonal antibodies. Results . 246 patients carrying either t(4;14) (n=106 patients), del(17p) (n=121 patients) or both (n=19 patients) were included. Median age was 64 years (range, 35-91). ISS and R-ISS score were 3 in 88 patients (36%). Eighty-seven patients (35%) were diagnosed in 2001-2010 period, and 159 (65%) in 2011-2019 period. Front-line autologous stem-cell transplantation (ASCT) was performed in 121 (49%) patients. Among transplant eligible patients, 112 patients (n=93%) received triplet induction, 78 patients (64%) a consolidation regimen and 15 patients (12%) a maintenance therapy. Double-ASCT was decided in 21 patients (17%). Among transplant ineligible patients, 61 patients (49%) received melphalan-based regimen in first line, 36 (29%) a bortezomib-based and 15 patients (14%) a lenalidomide-based regimen. At any line, 92 patients (37%) received at least one of the new agents with only 12 patients (5%) in frontline therapy. Median follow-up was 41 months (IQR: 21-69). Median overall survival (OS) was 58.4 months (IQR: 50.1-66.5) for the entire cohort, 55.5 months (IQR: 46.6-78.3) for del(17p), 62.5 months (IQR: 54.2-76.1) for t(4;14) and 48.6 months (18.1-not reached) for patients with both (p=0.2). Median of first progression-free survival (PFS1) was 25.6 months (IQR: 22.2-29.8), with no difference between del(17p), t(4;14) or both (p=0.57). Importantly, no improvement of median OS was observed in patients diagnosed between 2001-2010 in comparison with patients diagnosed between 2011-2019 (63.7 versus 53.2 months, p=0.32). In univariate and multivariate analysis: age (continuous and cut-off 71 years-old) and ASCT significantly were associated with risk of death (HR: 1.03, 1.09 and 0.45, respectively). Median OS of patients eligible to ASCT was 76.1 months (IQR: 62.5-90.3) vs 42.5 months (IQR: 36.8-54.6) for patients not eligible (HR 0.45, 95%CI 0.28-0.0.71; p Conclusion . This large multicenter real-world study confirms that patients with newly diagnosed MM carrying del(17p) and/or t(4;14) remain a therapeutic challenge with no significant overall survival improvement in the past decades despite the use of novel agents. The definition of high-risk MM patients is evolving with incorporation of new markers (i.e chromosome 1 abnormalities, PET-imaging). Minimal-residual disease achievement will also re-defined risk stratification. Nonetheless, the need for innovative approaches such as earlier strategies using new agents or immunotherapy (CAR-T cells, bispecific T-cell engager antibodies) may significantly improve outcomes. Figure captions Table 1. Clinical, biological characteristics, treatment and survival of the 246 included patients based on period of diagnosis. IQR: interquartile range; FISH: fluorescence in situ hybridization; ISS: international score system; LDH: lactate dehydrogenase; ASCT: autologous stem cell transplantation; len: lenalidomide; Poma: pomalidomide; Carfil: carfilzomib; Ixa: ixazomib; mAb: monoclonal antibodies; OS: overall survival Figure 1. Kaplan-Meier curves for overall survival for the 246 included patients based on period of diagnosis. Figure 1 Disclosures Moreau: Amgen: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Celgene/Bristol-Myers Squibb: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Novartis: Honoraria; Takeda: Honoraria. Touzeau:Takeda: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; Sanofi: Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Research Funding; Amgen: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; GlaxoSmithKline: Honoraria, Research Funding.

Background Long-term PI-based treatment is associated with improved outcomes in MM. Nonetheless, prolonged therapy with parenteral PIs (e.g. bortezomib) can be challenging in the real world, with median duration of therapy (DOT) of 4-7 months. Barriers to this long-term approach may include the burden of repeated intravenous/subcutaneous administration, difficulty travelling to/accessing treatment centers (e.g. due to environmental factors, travel restrictions, social/family situations), patient preference for treatment outside of a hospital or clinic setting, comorbidities, and toxicity. The US MM-6 study (NCT03173092) is investigating in-class transition (iCT) from parenteral bortezomib-based induction to all-oral ixazomib-based therapy (ixazomib-lenalidomide-dexamethasone; IRd) in the diverse US community population with the aim of increasing PI-based treatment duration while maintaining quality of life and improving outcomes. We report updated efficacy and safety for the first 101 patients. Methods Transplant-ineligible/delayed-transplant (>24 months) NDMM patients with stable disease or better after 3 cycles of bortezomib-based induction are being enrolled at US community sites (including Veterans Affairs hospitals) to receive IRd (ixazomib 4 mg, days 1, 8, 15; lenalidomide 25 mg, days 1-21; dexamethasone 40 mg, days 1, 8, 15, 22) for up to 39 x 28-day cycles or until progression/toxicity. The primary endpoint is progression-free survival (PFS); key secondary endpoints include rates of partial (PR), very good PR (VGPR), and complete response (CR), and DOT. Results As of June 1 2020, 101 patients had been treated at 21 sites. Median age was 73 years (range 48-90), with 46% aged ≥75 years; 16% and 10% were of African American and Hispanic ethnicity, respectively. Table 1 summarizes the key characteristics of these real-world patients. A total of 95% of patients had ≥1 comorbidity at the start of IRd therapy including renal and urinary disorders (38%), cardiac disorders (29%), peripheral neuropathy (PN; 14%), and diabetes mellitus (13%) (Table 2). With 53 (52%) patients remaining on therapy and enrollment ongoing, mean duration of PI therapy from the start of bortezomib-based induction was 12.4 months, and mean duration of IRd therapy after iCT was 9.2 months (Table 3). Patients have received up to 29.4 months (31 cycles) of IRd to date. The overall response rate (ORR) after bortezomib-based induction was 62% (7% CR, 32% ≥VGPR). After iCT to IRd, the ORR increased to 71%, with the CR and ≥VGPR rates increasing to 29% and 53%, respectively (Figure); of 33 patients with stable disease following bortezomib-based induction, 14 (42%) achieved CR (n=10) or VGPR (n=4) after iCT. With a median follow-up of 12 months and enrollment ongoing, 13 patients had progressed and two had died during PFS analysis. The 12-month PFS rate was 84% (95% CI, 73-91) from the start of bortezomib-based induction and 80% (95% CI, 69-88) from the start of IRd. During IRd treatment to date, 91% of patients have had treatment-emergent adverse events (TEAEs) (54% grade ≥3). Grade 3 TEAEs (≥5% of patients) were diarrhea (8%), pneumonia (7%), and syncope (5%). TEAEs led to study drug modification in 52% of patients and discontinuation in 7% of patients; 37% had serious TEAEs. Diarrhea, nausea, and vomiting occurred in 43%, 23%, and 14% of patients (8%, 2%, 2% grade 3), and led to dose modification in 11%, 5%, and 2%. PN (not elsewhere classified; high-level term) occurred in 32% of patients (2% grade 3) and led to dose modification in 9%. There were three on-study deaths (i.e. occurring Conclusions US MM-6 patients reflect the heterogeneous real-world US MM population; the population for this study includes patients from the community who may not be eligible for traditional clinical trials. These updated data in mostly elderly, comorbid, NDMM patients treated in the community setting demonstrate the feasibility and tolerability of iCT to IRd after 3 cycles of bortezomib-based induction; approximately half of patients remain on treatment, and enrollment is ongoing. iCT to IRd resulted in improved responses, with increased rates of ≥VGPR, and prolonged DOT and may thereby improve outcomes for real-world patients. iCT to an all oral regimen could also prevent treatment interruptions for patients who are unable to or prefer not to travel in the context of travel restrictions or other factors. Disclosures Girnius: Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Yimer:TG Therapeutics: Consultancy; AstraZeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Speakers Bureau; Sanofi: Speakers Bureau; Texas Oncology: Current Employment; BeiGene: Other: TRAVEL, ACCOMODATIONS, EXPENSES (paid by any for-profit health care company), Research Funding, Speakers Bureau; Janssen: Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Research Funding, Speakers Bureau; Takeda: Speakers Bureau; Celgene, a Bristol-Myers Squibb Company: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Speakers Bureau; Karyopharm: Consultancy, Divested equity in a private or publicly-traded company in the past 24 months, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Speakers Bureau; Epizyme: Consultancy, Divested equity in a private or publicly-traded company in the past 24 months. Noga:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Manda:AbbVie: Other: Investigator in AbbVie-sponsored clinical trials. Lyons:Texas Oncology/US Oncology: Current Employment; Novartis: Honoraria. Bogard:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Whidden:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Cherepanov:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Lu:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Aiello:Takeda: Honoraria; Travera: Honoraria; Celgene: Honoraria; Karyopharm: Honoraria. Richter:Celgene: Consultancy, Speakers Bureau; Adaptive Biotechnologies: Consultancy, Speakers Bureau; Janssen: Speakers Bureau; Sanofi: Consultancy; Karyopharm: Consultancy; Takeda: Consultancy; AstraZeneca: Consultancy; Secura Bio: Consultancy; Bristol Myers Squibb: Consultancy; X4 Pharmaceuticals: Consultancy; Oncopeptides: Consultancy; Antengene: Consultancy. Rifkin:McKesson: Current equity holder in publicly-traded company, Ended employment in the past 24 months, Other: Stock ownership; Takeda, Amgen, Celgene, BMS, Mylan, Coherus BioSciences, Fresenius: Consultancy; AbbVie: Other: Investigator in AbbVie sponsored clinical trials; Takeda, Amgen, BMS (Celgene): Membership on an entity's Board of Directors or advisory committees. OffLabel Disclosure: Real-world evaluation of long-term proteasome inhibition with ixazomib in combination with lenalidomide and dexamethasone for the treatment of newly diagnosed multiple myeloma in non-transplant patients with stable disease after 3 cycles of a bortezomib-based induction.

Background It is becoming increasingly important in the treatment of MM to improve our understanding of routine clinical practice and of the effectiveness of new agents and regimens outside the clinical trial setting. UVEA-IXA is a European, multicenter, observational, longitudinal cohort study of RRMM pts who received therapy with ixazomib, the first oral proteasome inhibitor (PI), at MM specialist centers via an Early Access Program (EAP) in 8 European countries (Czech Republic, Greece, Hungary, Italy, Slovakia, Slovenia, Spain, UK). Ixazomib was available in Europe via the EAP from Nov 2015, when it was initially approved in the US in combination with lenalidomide and dexamethasone for the treatment of MM pts who have received ≥1 prior therapy, until European approval in Nov 2016. Approvals were based on the results of the phase 3 TOURMALINE-MM1 study (Moreau NEJM 2016). We report data from the second interim analysis of pts enrolled in the UVEA-IXA study. Methods The UVEA-IXA observation period comprises two parts: a retrospective chart review, starting from ixazomib therapy initiation in the EAP, followed by a 1-yr prospective follow-up period from the date of chart abstraction, with data captured quarterly per local regulations. Pts eligible for the UVEA-IXA study were adult MM pts in biochemical and/or symptomatic relapse after 1-3 prior lines of therapy, who had not received any anti-MM therapy for >3 cycles (except steroids) at the time of ixazomib therapy initiation, and who had an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-2. Lenalidomide- or PI-refractory (disease progression on treatment or within 60 d after last dose) pts were excluded from UVEA-IXA. The primary endpoints of UVEA-IXA were response (per International Myeloma Working Group criteria) and progression-free survival (PFS; from ixazomib therapy initiation in the EAP to first documented disease progression/death during the observation period). Results A total of 359 pts were enrolled into UVEA-IXA. At data cutoff (May 22, 2020), 302 pts were evaluable for analysis; 55% were male; median age at enrollment was 68 yrs (range 36-92), with 39% aged ≥70 yrs. At the time of initiating ixazomib therapy, 36/117 (31%) pts had International Staging System (ISS) stage III disease, and 61/301 (20%) had an ECOG PS of 2; 60% of all evaluable pts had ≥1 comorbidity, including hypertension (26%), renal disease (23%), and diabetes (10%). Median time from MM diagnosis was 37.0 mos (range 4.9-231.7), and 39%, 43%, and 18% of pts had received 1, 2, and 3 prior lines of therapy. These included (in any line) bortezomib (89%), thalidomide (52%), transplant (47%), melphalan (22%), lenalidomide (17%), carfilzomib (5%), and pomalidomide (2%). The median follow-up period among 295 pts with available data was 24.9 mos (range 0.2-49.3); of all evaluable pts, 160 (53%) discontinued the study (of these, 88% discontinued due to death). Pts received ixazomib for a median of 10.8 mos (range 0.2-49.3), and most pts also received lenalidomide (97%) and dexamethasone (96%). Among 275 pts with data on best response, the overall response rate (ORR) was 60% (Table 1). Median PFS was 15.6 mos (95% CI 11.8-20.0; Figure). Ixazomib and lenalidomide dose reductions and discontinuations are summarized in Table 2. In 187 pts who received ≥4 cycles of ixazomib, rates of any-grade, grade ≥3, and serious adverse events (AEs) were 60%, 33%, and 23%; the most common AEs of any grade were diarrhea and thrombocytopenia (14% each), rash (7%), peripheral neuropathy (6%), and nausea/vomiting (5%); the most common grade ≥3 AE was thrombocytopenia (6%). Conclusions Data from the second interim analysis of UVEA-IXA demonstrate that ixazomib-based therapy is effective outside the clinical trial setting, with an ORR of 60% and a median PFS of 15.6 mos. Compared with TOURMALINE-MM1 pts (ixazomib arm; ORR 78%, median PFS 20.6 mos), UVEA-IXA pts have higher rates of ECOG PS 2 (20% vs 5%) and ISS stage III MM (31% vs 12%), and had received more prior therapies (61% vs 38% had ≥2 prior therapies). The most common AEs were gastrointestinal and hematologic AEs, in line with the well-characterized and manageable safety profile of ixazomib, although data are not directly comparable with clinical trial safety data due to the retrospective/infrequent prospective collection schedule. Ixazomib-based therapy is an effective and tolerable treatment option outside the clinical trial setting. Disclosures Ludwig: Celgene: Speakers Bureau; Amgen: Other: Advisory Boards, Research Funding, Speakers Bureau; Takeda: Research Funding; Seattle Genetics: Other: Advisory Boards; Janssen: Other: Advisory Boards, Speakers Bureau; Bristol Myers: Other: Advisory Boards, Speakers Bureau; Sanofi: Other: Advisory Boards, Speakers Bureau. Terpos:Genesis: Research Funding; Sanofi: Honoraria; Genesis: Honoraria; Amgen: Honoraria; Janssen: Honoraria; Takeda: Honoraria; Janssen: Research Funding; Takeda: Research Funding; BMS: Honoraria; Amgen: Research Funding; Celgene: Honoraria. Mateos:Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Honoraria; Regeneron: Honoraria, Membership on an entity's Board of Directors or advisory committees. Boccadoro:Mundipharma: Research Funding; Amgen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; GlaxoSmithKline: Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria; Bristol-Myers Squibb: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Kishore:Celgene: Other. Ramasamy:Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; BMS: Consultancy, Research Funding, Speakers Bureau; Takeda: Consultancy, Research Funding, Speakers Bureau; Oncopeptides: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Research Funding. Fernandez:MediNeos Observational Research: Current Employment. Ferri:MediNeos Observational Research: Current Employment. Bent-Ennakhil:Takeda Pharmaceuticals International AG: Current Employment. Zomas:Takeda Pharmaceuticals International AG: Current Employment. Gavini:Takeda Pharmaceuticals International AG: Current Employment. Hajek:Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharma MAR: Consultancy, Honoraria; BMS: Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Oncopeptides: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding.

With the advent new proteasome inhibitors (carfilzomib, ixazomib), new immune-modulatory drugs (pomalidomide), and new monoclonal antibodies (elotuzimab, daratumumab) as approved treatments for myeloma, the therapeutic landscape for this disease has changed. In this chapter, using a case-based approach, I will provide a personal guide of how I approach myeloma therapy in a transplant eligible patient in 2018.

Introduction: Treatment of relapsed and refractory multiple myeloma (RRMM) continues to evolve as most patients are lenalidomide (LEN) refractory at the time of first relapse with its widespread use in both induction and maintenance therapy. Pomalidomide, bortezomib and dexamethasone in RRMM has demonstrated significant activity and improvement in progression-free survival in LEN-refractory patients (Richardson et al Lancet Oncol 2019 Jun;20(6):781-794). Ixazomib is a novel oral proteasome inhibitor (PI) that is currently approved in combination with LEN and dexamethasone in RRMM. Ixazomib is administered on a once weekly schedule and its oral route of administration is particularly attractive, not least in the context of the current COVID-19 pandemic. Twice weekly dosing of ixazomib has been studied in combination with LEN demonstrating promising activity in NDMM (Richardson et al, Br J Haematol. 2018 Jul;182(2):231-244). Moreover, safety and efficacy has been shown in RRMM as twice weekly monotherapy on this schedule (Richardson et al, Blood 2014 Aug 14;124(7):1038-46). We hypothesized that a twice weekly ixazomib schedule in combination with pomalidomide and dexamethasone will lead to enhanced efficacy and comparable safety in RRMM. Methods: This is a phase I/II multicenter, single-arm, open label study evaluating the combination of twice weekly ixazomib with pomalidomide and dexamethasone in RRMM. Primary objective for phase I portion is to determine safety and the maximum tolerated dose (MTD) of this combination using a standard 3+3 dose escalation design. Ixazomib is studied at doses of 3mg or 4mg on days 1, 4, 8, 11, pomalidomide at a dose of 2mg, 3mg and 4mg on days 1-14 and dexamethasone is administered at a dose of 12mg on days 1, 2, 4, 5, 8, 9, 11, 12 (8mg for patients > 75 years old) on a 21 day cycle (Table 1). Patients were included if they received 2 prior lines of therapy, but 1 prior line was allowed if first line treatment included a PI and an immunomodulatory agent and disease relapse occurred within 60 days of last therapy. Patients who received prior ixazomib were excluded. Results: At the time of data cutoff, 12 patients have been enrolled across cohorts 0, 1 and 2 and enrollment in the final cohort 3 is ongoing. Median age at the time of enrollment was 70 years old with slight male predominance (58%). ISS stage at diagnosis was II or greater in 75% of patients and 9 out of 12 (75%) patients had high-risk FISH as follows: del 17p (17%), gain 1q (50%), and t(4;14) (8%). Median prior lines of therapy was 2 (range 1-3) with 100% of patients having prior treatment with lenalidomide and 92% with prior bortezomib. Forty-two percent of patients had a prior autologous stem cell transplant. Most common treatment-related toxicities were mainly low grade and included neutropenia (58%), hyperglycemia (42%), fatigue (33%), anemia (25%), thrombocytopenia (25%), and rash (25%). Grade 3 or greater toxicities included neutropenia (17%), anemia (8%), bacterial lung infection (8%), and atrial fibrillation (8%). There was 1 dose limiting toxicity (DLT) in cohort 2 due to lung infection necessitating a delay in initiation of cycle 2 and no further DLTs have been noted. Dose reductions occurred in 4 patients and predominantly involved dexamethasone due to weight gain, insomnia, atrial fibrillation and fatigue. There have been no discontinuations due to toxicity and no treatment related mortality at the time of data cutoff. In response evaluable patients, 5 out of 12 patients have demonstrated a partial response or better (42%), with 1 very good partial response (VGPR) and all patients at least achieving stable disease. Conclusions: Twice weekly ixazomib in combination with pomalidomide and dexamethasone is a generally well-tolerated regimen with promising early activity in a high-risk RRMM cohort. Maximal tolerated dose and recommend phase II dose has not yet been reached and this study continues to accrue robustly, reflecting in part the convenience and safety of an all oral approach in the current era of COVID-19. Moreover, the ability to perform remote laboratory testing, telemedicine visits and to send medications directly to patients has been an additional value-add to this trial. Updated data will be presented at the meeting. Disclosures Nadeem: Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Adaptive: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES. Mo:Celgene: Membership on an entity's Board of Directors or advisory committees. Barth:Sanofi: Membership on an entity's Board of Directors or advisory committees. Sanchorawala:Takeda: Research Funding; Celgene: Research Funding; Prothena: Research Funding; Caelum: Research Funding; Oncopeptide: Research Funding; Regeneron: Other: advisory board; Caleum: Other: advisory board; Proclara: Other: advisory board; Abbvie: Other: advisory board; UpToDate: Patents & Royalties; Janssen: Research Funding. Munshi:BMS: Consultancy; OncoPep: Consultancy, Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties; C4: Current equity holder in private company; Janssen: Consultancy; Adaptive: Consultancy; Legend: Consultancy; Amgen: Consultancy; AbbVie: Consultancy; Karyopharm: Consultancy; Takeda: Consultancy. Ghobrial:Celgene: Consultancy, Honoraria; GlaxoSmithKline: Consultancy; Genentech: Consultancy; Novartis: Consultancy; Noxxon Pharma: Consultancy; Adaptive Biotechnologies: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Cellectar: Honoraria; Karyopharm Therapeutics: Consultancy, Honoraria; GNS Healthcare: Consultancy; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; AbbVie: Consultancy; Takeda: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria. Anderson:Oncopep and C4 Therapeutics.: Other: Scientific Founder of Oncopep and C4 Therapeutics.; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Sanofi-Aventis: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Millenium-Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Richardson:Celgene/BMS, Oncopeptides, Takeda, Karyopharm: Research Funding.

The management of Waldenström macroglobulinemia (WM) has evolved tremendously with recent genomic discoveries that correlate with clinical presentation and could help to tailor treatment approaches. The current diagnosis of WM requires clinicopathological criteria, including bone marrow involvement by lymphoplasmacytic lymphoma cells, a serum immunoglobulin M (IgM) monoclonal paraprotein, and presence of the MYD88 L265P mutation. Once the diagnosis is established, the relationship between the patient’s symptoms and WM should be carefully investigated, because therapy should be reserved for symptomatic patients. Bone marrow involvement and serum levels of IgM, albumin, and β2-microglobulin can be used to estimate the time until treatment initiation. The treatment of WM patients should be highly personalized, and the patient’s clinical presentation, comorbidities, genomic profile, and preferences, as well as toxicity of the treatment regimens, should be taken into account. Alkylating agents (bendamustine, cyclophosphamide), proteasome inhibitors (bortezomib, carfilzomib, ixazomib), anti-CD20 monoclonal antibodies (rituximab, ofatumumab), and Bruton tyrosine kinase (BTK) inhibitors (ibrutinib, acalabrutinib, zanubrutinib) are safe and highly effective treatment options in patients with WM. Because novel covalent and noncovalent BTK inhibitors (tirabrutinib, vecabrutinib, LOXO-305, ARQ-531), BCL2 antagonists (venetoclax), and CXCR4-targeting agents (ulocuplumab, mavorixafor) are undergoing clinical development in WM, the future of WM therapy certainly appears bright and hopeful.

Proteasome inhibition results in extensive immunomodulatory effects that augment natural killer cell cytotoxicity and inhibit aspects of T-cell, B-cell, and dendritic cell function. We performed a phase 2 study that examined the effects of ixazomib for graft-versus-host disease (GVHD) prophylaxis (up to 12 cycles) with posttransplant cyclophosphamide and tacrolimus after standard nonmyeloablative haploidentical donor transplantation (HIDT). Ixazomib was started on day +5 (4 mg on days 1, 8, and 15 of a 28-day cycle), with dose reductions allowed in future cycles for toxicity. All patients received peripheral blood stem cells. Twenty-five patients were enrolled with a median age of 62 years (range, 35-77 years) who had acute leukemia (4), myelodysplastic syndrome (7), non-Hodgkin lymphoma/Hodgkin lymphoma/chronic lymphocytic leukemia (8), and myeloma (6). The hematopoietic cell transplant comorbidity index was ≥3 in 68% of the patients. After a median follow-up of 33.5 months, the cumulative incidence of relapse/progression at 1 year was 24% and 44% at 3 years, which failed to meet the statistically predefined goal of decreasing 1-year risk of relapse. Engraftment occurred in all patients with no secondary graft failure, and 3-year nonrelapse mortality (NRM) was 12%. Cumulative incidence of grade 3 to 4 acute GVHD was 8%, whereas moderate-to-severe chronic GVHD occurred in 19%. Nineteen patients survive with an estimated 1-year overall survival (OS) of 84% and 3-year OS of 74%. Hematologic and cutaneous toxicities were common but manageable. The substitution of ixazomib for mycophenolate mofetil (MMF) post-HIDT results in reliable engraftment, comparable rates of clinically significant GVHD, relapse and NRM, and favorable OS. This trial was registered at www.clinicaltrials.gov as # NCT02169791.

Proteasome inhibitors bortezomib, carfilzomib and ixazomib (approved by the US Food and Drug Administration [FDA]) induce remissions in patients with multiple myeloma (MM), but most patients eventually become resistant. MM and other hematologic malignancies express ubiquitous constitutive proteasomes and lymphoid tissue–specific immunoproteasomes; immunoproteasome expression is increased in resistant patients. Immunoproteasomes contain 3 distinct pairs of active sites, β5i, β1i, and β2i, which are different from their constitutive β5c, β1c, and β2c counterparts. Bortezomib and carfilzomib block β5c and β5i sites. We report here that pharmacologically relevant concentrations of β5i-specific inhibitor ONX-0914 show cytotoxicity in MM cell lines similar to that of carfilzomib and bortezomib. In addition, increasing immunoproteasome expression by interferon-γ increases sensitivity to ONX-0914 but not to carfilzomib. LU-102, an inhibitor of β2 sites, dramatically sensitizes MM cell lines and primary cells to ONX-0914. ONX-0914 synergizes with all FDA-approved proteasome inhibitors in MM in vitro and in vivo. Thus, immunoproteasome inhibitors, currently in clinical trials for the treatment of autoimmune diseases, should also be considered for the treatment of MM.

Background: Clinical data support the combination of an immunomodulatory drug, a proteasome inhibitor, and a glucocorticoid for the treatment of newly diagnosed multiple myeloma (NDMM). The combination of lenalidomide, bortezomib, and low-dose dexamethasone is a very active, well-tolerated standard of care in the transplant-ineligible NDMM population. Ixazomib, an oral proteasome inhibitor is approved by the US Food and Drug Administration in combination with lenalidomide and dexamethasone for the treatment of relapsed MM. Given that ixazomib has improved binding kinetics and pharmacologic profile compared with bortezomib, it is expected that these differences will translate into similar, if not improved, efficacy and safety profiles in the upfront setting. A phase l/ll study of lenalidomide, ixazomib, and dexamethasone in previously untreated patients with MM demonstrated that this combination was well-tolerated and active (NCT01217957). More recently, the GRIFFIN study evaluated the addition of the anti-CD38 monoclonal antibody, daratumumab to lenalidomide, bortezomib, and dexamethasone in transplant-eligible NDMM and demonstrated the ability of daratumumab to improve efficacy of the three-drug combination with an acceptable safety profile. Building upon these data, our study evaluates the addition of daratumumab to the all-oral regimen of lenalidomide, ixazomib, and dexamethasone in transplant-ineligible NDMM. The combination proposed in this study has been evaluated in NDMM irrespective of transplant eligibility and has demonstrated excellent efficacy and tolerability. Responses were rapid with 88% achieving a partial response (PR) or better after 2 cycles (33% very good partial response (VGPR) and 52% VGPR for 29 patients who had completed 4 cycles) with an overall response rate of 95%. 1 In our study, transplant-ineligible NDMM patients will be randomized to receive 12 cycles of induction with lenalidomide, ixazomib, dexamethasone, and daratumumab followed by lenalidomide alone versus lenalidomide, ixazomib, and daratumumab. Study Design and Methods: A randomized, phase II clinical trial (NCT04009109) is being conducted to assess the impact on progression-free survival (PFS) of the addition of ixazomib and daratumumab to lenalidomide as maintenance treatment following induction with lenalidomide, ixazomib, dexamethasone, and daratumumab. In this ongoing trial, eligible patients are randomized 1:1 to Arm A (12 cycles of lenalidomide, ixazomib, dexamethasone, and daratumumab followed by lenalidomide until disease progression or unacceptable toxicity or a maximum of 2 years of maintenance therapy) vs. Arm B (12 cycles of lenalidomide, ixazomib, dexamethasone, and daratumumab, followed by lenalidomide, ixazomib, and daratumumab until disease progression or unacceptable toxicity or a maximum of 2 years maintenance therapy). Eligible patients have NDMM requiring treatment, are ≥18 years, have ECOG PS of 0-2, and must have been deemed ineligible for stem cell transplantation. The primary endpoint is PFS. With a sample size of 188 patients (94 patients per arm) enrolled over a 36-month period and followed for a minimum of 24 months after the close of enrollment, a one-sided alpha=0.10 log rank test will have an 85% chance of detecting an increase in median PFS time from 30 months to 48 months (a hazard ratio of 0.625) with the addition of ixazomib and daratumumab to lenalidomide as a maintenance treatment following induction with ixazomib, lenalidomide, dexamethasone, and daratumumab. Secondary outcomes of interest include minimal residual disease, overall survival, changes in body composition, quality of life, psychosocial measures of functional status including social activity and support, psychological state, and nutrition using a geriatric assessment tool, and the association of these psychosocial measures with therapy-associated toxicities. 1Kapoor et al. Blood (2019) 134 (Supplement_1): 864. Support: Alliance Foundation Trials; Janssen, Takeda, Celgene; https://acknowledgments.alliancefound.org Figure 1 Figure 1. Disclosures O'Donnell: Bristol Myer Squibb: Consultancy; Janssen: Consultancy; Takeda: Consultancy; Oncopeptide: Consultancy; Adaptive: Consultancy; Karyopharm: Consultancy. Nadeem: GSK: Consultancy; Karyopharm: Consultancy; Adaptive: Consultancy; Takeda: Consultancy; Bristol Myer Squibb: Consultancy. Dinner: Kite/Gilead: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria. Yee: Takeda: Consultancy; Sanofi: Consultancy; Bristol Myers Squibb: Consultancy; Oncopeptides: Consultancy; Janssen: Consultancy; Karyopharm: Consultancy; Amgen: Consultancy; Adaptive: Consultancy; GSK: Consultancy. Mo: Karyopharm: Honoraria, Membership on an entity's Board of Directors or advisory committees; Epizyme: Consultancy; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Eli Lilly: Consultancy. Tuchman: Karyopharm: Research Funding; Shattuck Labs: Consultancy; Sanofi / Genzyme: Consultancy, Research Funding; Caelum: Consultancy, Research Funding; Oncopeptides: Consultancy. Raje: Caribou: Other; Janssen: Other; bluebird bio: Other; Amgen: Other; Celgene: Other; BMS: Other. Richardson: AstraZeneca: Consultancy; Regeneron: Consultancy; Janssen: Consultancy; Celgene/BMS: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; Oncopeptides: Consultancy, Research Funding; GlaxoSmithKline: Consultancy; Secura Bio: Consultancy; Sanofi: Consultancy; Protocol Intelligence: Consultancy; Karyopharm: Consultancy, Research Funding; AbbVie: Consultancy; Jazz Pharmaceuticals: Consultancy, Research Funding.

Introduction Non-transplant eligible newly diagnosed multiple myeloma (NTE-NDMM) patients have a heterogeneous clinical outcome, which can be partly explained by differences in frailty level. Accordingly, intermediate-fit patients, according to the IMWG frailty index, have an inferior survival and higher rates of treatment discontinuation as compared to fit NTE-NDMM patients. The aim of this study was to prospectively investigate the efficacy and tolerability of the novel regimen ixazomib-daratumumab-low dose dexamethasone in intermediate-fit NTE-NDMM patients. This trail is registered at www.trialregister.nl as NTR6297. Methods In the phase II HOVON 143 study, intermediate-fit NTE-NDMM patients were treated with nine 28-day induction cycles, consisting of ixazomib 4mg (day 1, 8, 15), daratumumab 16mg/kg (cycle 1-2 on day 1, 8, 15, 22; cycle 3-6 on day 1, 15; cycle 7-9 on day 1) and dexamethasone (on days of daratumumab; cycle 1-2 20mg, subsequent cycles 10mg), followed by maintenance therapy of 8-week cycles with ixazomib (days 1, 8, 15, 29, 36, 43), and daratumumab (day 1), of maximum 2 years or until earlier progression. Inclusion criteria were NTE-NDMM patients who were intermediate-fit according to the IMWG frailty index. Main exclusion criteria were severe cardiac dysfunction, chronic obstructive pulmonary disease with an FEV1 The primary endpoint was overall response rate (ORR) after nine induction cycles, defined by having at least a partial response (≥PR). Secondary endpoints were PFS, OS, event free survival (EFS, defined as either treatment discontinuation, progressive disease (PD), death, hematological adverse events (AE) grade 4 or non-hematological AE grade 3/4), and health-related quality of life (using the EORTC-QLQ C30 and -MY20). Results Sixty-five NTE-NDMM patients were included in the study of whom the demographics are described in Table 1. Median age was 76 years (range 65-80), 14% had a WHO≥2, 18% had ISS3 and 14% had high-risk cytogenetic abnormalities. The ORR was 71% (95% CI 63-73), including 23 (35%) patients with a very good partial response and 1 (2%) with a complete response. After a median follow-up time of 18.1 months (range 9.5-27.8), the median PFS was 17.4 months (95% CI 10.4-22.6), the median OS was not reached and 12-month OS was 92% (95% CI 82-97)(Figure 1). Eight patients died, 3/65 (5%) due to relapse and 5/65 (8%) due to other reasons, including one early death (≤60 days from registration). The median EFS was 5.3 months (95% CI 2.8-8.3). EFS defining events were non-hematological AEs grade 3/4 in 31 (48%), PD in 15 (23%), hematological AEs grade 4 in 2 (3%), treatment discontinuation in 2 (3%) and death in 1 (2%) patients (Figure 1). Thirty/65 (46%) patients did not proceed to maintenance therapy, due to PD (19/65 (29%)), toxicity (4/65 (6%)), incompliance (3/65 (5%)), sudden death (1/65 (2%)) or other reasons (3/65 (5%)). In addition, 7/65 (11%) patients had to discontinue ixazomib-only, all 7 due to PNP. Cumulative grade 3 or higher hematological AEs occurred in 8/65 (12%), mainly neutropenia (6%), whereas grade ≥3 non-hematological AEs were reported in 33/65 (51%) patients. Most common non-hematological grade ≥3 AEs were gastro-intestinal (14%), central nervous system AEs (11%) or infections (9%). Of 27/65 (42%) patients experiencing PNP, 4 (8%) had PNP grade 3. During induction, patients experienced a statistically and clinically (reaching minimal important difference thresholds) significant improvement in GHS/QoL, role functioning, and future perspective. In contrast, PNP worsened over time. Conclusion In intermediate-fit patients, ixazomib, daratumumab and dexamethasone is an effective and feasible regime, which improves QoL. However, treatment discontinuation due to toxicity (either the whole regimen (6%), but especially ixazomib only (11%)) or incompliance, which negatively affects PFS, remains a concern. This underscores the need to investigate novel monoclonal antibody-based treatment combinations with a higher efficacy to tolerability balance for intermediate-fit patients with NDMM. Figure 1 Figure 1. Disclosures Vekemans: Amgen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees. van de Donk: Janssen Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; Cellectis: Research Funding; Servier: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive Biotechnologies: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees. Timmers: Gilead Sciences: Other: Travel, Accommodations, Expenses; Daiichi Sankyo Ned: Membership on an entity's Board of Directors or advisory committees; Servier: Speakers Bureau; Janssen-Cilag: Membership on an entity's Board of Directors or advisory committees; Novartis: Speakers Bureau. Sonneveld: Karyopharm: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Celgene/BMS: Consultancy, Honoraria, Research Funding; SkylineDx: Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding. van der Spek: Amgen: Other. De Waal: Celgene: Speakers Bureau; Roche: Other: Travel, Accommodations, Expenses. Nijhof: Janssen: Membership on an entity's Board of Directors or advisory committees; Celgene/Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees. Levin: Roche, Janssen, Abbvie: Other: Travel Expenses, Ad-Board. Zweegman: Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding.

Purpose: Frail patients with multiple myeloma have an inferior outcome, especially in the relapse setting. This adverse prognosis is mainly related to a high discontinuation rate due to treatment related adverse events. The aim of this phase 2 study is to evaluate efficacy and tolerability of Ixazomib-Daratumumab (I-Dara) without Dexamethasone in elderly frail patients with relapsed myeloma (NCT03757221). Methods: Fifty Ixa-Dara naïve RRMM patients (1-2 prior therapy) were planned to receive oral Ixa (4 mg: days 1, 8, 15), IV Dara (16 mg/kg; days 1, 8, 15, 22, cycles 1-2; days 1, 15, cycles 3-6; days 1, cycles 7+) and IV Methylprednisolone before Dara (100 mg at day 1, 8, cycle 1 and then 60 mg). They were enrolled if frailty score was ≥2 by IMWG score and FIRST proxy score (Facon T et al, Leukemia, 2020). The primary endpoint was ≥very good partial response rate at one year. Secondary endpoints included ORR, PFS, OS & toxicity according to NCI-CTCAE version 5.0. Results: Among 52 patients screened during this ongoing trial, 44 were included between 03/2018 and 05/2021. Patient were at first (n=28) or second relapse (n=16). Thirty -eight patients (86%) were previously exposed to bortezomib and 8 (18%) were previously refractory to lenalidomide. Median age was 82 (80-84). All patients had a frailty score ≥2. In 22 patients ISS was stage I (n=5), II (n=10) or III (n=7). Eleven (32%) patients harbored high-risk cytogenetic, including t(4;14) (n=3) or del17p (n=8). The median duration of Tx among 23 pts with ongoing Tx was 6 months [0-27] at data cutoff (July 19)]. The median duration of Tx among 21 pts who stopped Tx was 7 months [0-21]: 13 had progressive disease. Six patients died during the study: Daratumumab-related bronchospasm (D1C1); Ixazomib-related overdose (C2); progressive disease (C2 & C4), sepsis (C1 & C2). Regarding toxicity, 28 ≥grade 3 AE occurred amongst 24 pts (54%). The most common grade 3-4 toxicities were thrombocytopenia (n=5), other cytopenias (n=4), infection (n=4) and gastrointestinal disorders (n=2). Fourteen out of 28 were SAE including 1 bronchospasm, 1 acute respiratory failure and 2 ixazomib overdoses. Overall response rate, including minimal response, was 86 % in pts with ongoing treatment and 71% in pts who stopped Tx; ≥VGPR rate was 33% and 6% respectively. Conclusions: These preliminary results show a favorable safety profile of ixazomib and daratumumab combination, without dexamethasone, in this specific population of very elderly frail patients with RRMM and high risk cytogenetic for almost one third of them. Efficacy results will be analyzed when the 50 patients will be enrolled in the study and evaluable for the primary endpoint. Disclosures Macro: GSK: Honoraria; Sanofi: Honoraria; Celgen/BMS: Honoraria; Janssen: Honoraria, Other: Travel accomodation, Research Funding; Takeda: Honoraria, Other: Travel accomodation, Research Funding. Manier: Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive Biotechnologies: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Regeneron: Consultancy, Research Funding; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene - Bristol Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Vincent: Celgene: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees. Decaux: Amgen BMS Celgene Janssen Sanofi Takeda: Honoraria. Leleu: Bristol-Myers Squibb: Honoraria; Carsgen Therapeutics Ltd: Honoraria; Celgene: Honoraria; Gilead Sciences: Honoraria; Janssen-Cilag: Honoraria; Karyopharm Therapeutics: Honoraria; Merck: Honoraria; Mundipharma: Honoraria; Novartis: Honoraria; Oncopeptides: Honoraria; Pierre Fabre: Honoraria; Roche: Honoraria; Sanofi: Honoraria; Amgen: Honoraria; AbbVie: Honoraria; Takeda: Honoraria, Other: Non-financial support. OffLabel Disclosure: Ixazomib and Daratumumab association is not approved in NDMM or in RRMM

Background: Use of long-term PI-based therapy can improve outcomes across treatment settings in MM. However, there are various physical, geographical, and/or socioeconomic barriers to prolonged therapy with parenteral PIs in community practice. The US MM-6 study (NCT03173092) is assessing in-class transition (iCT) from parenteral bortezomib (V)-based induction to all-oral ixazomib-based therapy with ixazomib-lenalidomide-dexamethasone (IRd) in the diverse US community population. The objective of the study is to increase the duration of PI-based treatment, while maintaining quality of life and improving outcomes. We previously reported efficacy and safety results for the first 101 US MM-6 patients (Girnius Blood 2020). Here we have analyzed updated data for this patient subset with an additional 11 months of follow-up to further evaluate efficacy and safety, and to determine reasons for premature (within 4 cycles of IRd) discontinuation. Methods: Transplant-ineligible/delayed-transplant (≥24 months) NDMM patients at US community sites, who had achieved stable disease or better after 3 cycles of V-based induction, received IRd (ixazomib 4 mg, days 1, 8, 15; lenalidomide 25 mg, days 1-21; dexamethasone 40 mg, days 1, 8, 15, 22) for up to 39 × 28-day cycles or until disease progression or unacceptable toxicity. The primary endpoint is 2-year progression-free survival (PFS). Rates of partial response (PR), very good PR (VGPR), and complete response (CR), and duration of therapy are key secondary endpoints. For the current analysis, sites with patients who discontinued US MM-6 were queried for more detailed information. Results: As of June 1, 2020, 101 patients had been enrolled and treated at 21 sites. Median age was 73 years (range, 48-90 years), with 81% aged >65 years; 97% had ≥1 comorbidity at the start of IRd therapy. Efficacy data after an additional 11 months of follow-up (data cut-off: May 4, 2021) showed that iCT to IRd improved responses (Table 1). Overall response rate (ORR) had improved from 65% (CR 9%, VGPR 25%, PR 32%), at the end of 3 cycles of V-based induction, to 78% (molecular CR [mCR] 1%, stringent CR [sCR] 3%, CR 32%, VGPR 25%, PR 17%) following iCT to IRd. Thirty-three patients (33%) were still ongoing on therapy at the latest data cut-off; median duration of IRd was 11.7 months and overall median duration of therapy (for all PI-based therapy, including V-based induction) was 14.6 months. At a median follow-up of 18.5 months, the 18-month PFS rate was 84%. The safety profile of IRd was consistent with previous clinical studies. Grade ≥3 treatment-emergent adverse events (TEAEs) were reported in 64% of patients and treatment-related serious TEAEs in 12% (including 4 on-study deaths), while 16% of TEAEs led to study drug discontinuation. Sixty-eight patients (67%) had completed or discontinued the study since first patient enrolment on November 15, 2017. Among these patients, 14 (21%) discontinued within 2 cycles of IRd and 27 (40%) discontinued within 4 cycles; reasons for discontinuation are presented in Table 2. Conclusions: With longer follow-up, use of iCT from V-based induction to IRd to achieve long-term PI-based therapy in NDMM patients demonstrates efficacy via improved response rates and acceptable PFS in this real-world setting. Over 80% of US MM-6 patients were aged >65 years and most had ≥1 comorbidity prior to study entry. The rate of patients discontinuing within 4 cycles of iCT (7 cycles of PI-based therapy in total) is concerning because these patients may not receive the full benefit of long-term PI-based treatment. To date, the majority of premature discontinuations were reported as being due to patient request (44%) followed by TEAEs (30%). Expanded site education and closer patient follow-up to reduce premature discontinuations will be addressed in the planned US MM7 iCT study in relapsed/refractory MM. Figure 1 Figure 1. Disclosures Rifkin: Coherus: Membership on an entity's Board of Directors or advisory committees; Fresenius-Kabi: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; McKesson: Current Employment, Current equity holder in publicly-traded company; Amgen: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb (Celgene): Membership on an entity's Board of Directors or advisory committees. Noga: Takeda Oncology: Current Employment. Girnius: Beigene: Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; GSK: Honoraria, Speakers Bureau; Genentech: Honoraria; Celgene: Speakers Bureau; BMS: Honoraria, Speakers Bureau. Bogard: Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Manda: Morphosys: Honoraria; Genmab: Current equity holder in publicly-traded company. Yimer: Texas Oncology: Current Employment; Pharmacyclics: Speakers Bureau; Amgen: Speakers Bureau; Sanofi: Speakers Bureau; GSK: Speakers Bureau; Beigene: Speakers Bureau; Janssen: Speakers Bureau; Astrazeneca: Speakers Bureau; Karyopharm: Current equity holder in publicly-traded company, Speakers Bureau. Whidden: Takeda Oncology: Current Employment. Birhiray: Bayer: Honoraria; Incyte: Research Funding, Speakers Bureau; Takeda: Research Funding, Speakers Bureau; Seattle Genetics: Honoraria; Coheris: Honoraria; Kyte Pharma: Honoraria; Celgene: Honoraria; Helsin: Honoraria; Amgen: Honoraria, Speakers Bureau; Pfizer: Speakers Bureau; BMS: Speakers Bureau; Tessaro: Speakers Bureau; AstraZeneca: Speakers Bureau; Alexion: Consultancy; Abbvie: Consultancy, Honoraria; Lilly: Speakers Bureau; Exelexis: Speakers Bureau; Clovis Oncology: Speakers Bureau; Sanofi Oncology: Speakers Bureau; Genomic Health: Speakers Bureau; Puma: Consultancy, Research Funding, Speakers Bureau; Pharmacyclics: Consultancy, Speakers Bureau; Jansen Bioncology: Consultancy, Speakers Bureau; Novartis: Consultancy, Honoraria, Speakers Bureau. Twumasi-Ankrah: Takeda: Current Employment. Guo: Takeda Oncology: Current Employment. Bernal-Mizrachi: Kodikaz Therapeutic Solutions: Consultancy, Current holder of individual stocks in a privately-held company, Patents & Royalties; Bigene: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Winship Cancer Institute of Emory University: Current Employment. OffLabel Disclosure: Real-world evaluation of long-term use of the oral proteasome inhibitor ixazomib in combination with lenalidomide and dexamethasone for the treatment of newly diagnosed multiple myeloma in non-transplant patients with stable disease after 3 cycles of a bortezomib-based induction

Introduction The use of lenalidomide in frontline therapy for patients (pts) with newly diagnosed multiple myeloma (NDMM) has increased the number of pts who become refractory to lenalidomide at second line. Thus, there is an ongoing need for new treatment options for lenalidomide refractory patients at first relapse. Daratumumab, an anti-CD38 monoclonal antibody, has shown significant activity and acceptable safety in pts with relapsed/refractory multiple myeloma (RRMM) as monotherapy or in combination with other agents. Ixazomib, the first oral proteasome inhibitor, in combination with lenalidomide and dexamethasone also improves key survival endpoints in RRMM. This study assessed the efficacy of daratumumab in combination with ixazomib and dexamethasone (Dara-Ixa-dex) as second-line therapy in pts with RRMM who have been previously treated with a lenalidomide-based regimen. Methods DARIA is an ongoing, prospective, open-label, multicenter, phase 2 study. Eligible adult pts with RRMM had measurable disease after one prior line with a lenalidomide-based regimen and a Karnofsky Performance Status (KPS) score of ≥70. Exclusion criteria included previous anti-CD38 or ixazomib treatment, treatment with CYP3A inducers or use of St. John's wort within 14 days before C1D1, anti-myeloma treatment within 2 weeks or 5 pharmacokinetic half-lives of the treatment prior to C1D1 and allogenic or autologous stem cell transplantation (ASCT) within 12 weeks before C1D1. Treatment with Dara-Ixa-dex comprises an induction phase of nine 28-days cycles and a maintenance phase. In induction, pts received DARA 16mg/kg (weekly for cycles 1-2, bi-weekly for cycles 3-6, and every 4 weeks thereafter) administered intravenously until November 2020 and subcutaneously at a fixed dose of 1800 mg thereafter; 4mg oral ixazomib (days 1, 8, and 15 of each cycle); and 40mg oral dexamethasone (weekly, each cycle). In maintenance, Dara-Ixa were administered every 4 weeks until disease progression or unacceptable toxicity, with dexamethasone being discontinued. The primary endpoint was overall response rate (ORR). Secondary endpoints included progression-free survival (PFS), the toxicity profile of Dara-Ixa-dex, and the effects of the combination on serum bone metabolism markers (C-terminal telopeptide of type 1 collagen [CTX], tartrate-resistant acid phosphatase isoform 5b [TRACP-5b], bone-specific alkaline phosphatase [bALP], and osteocalcin [OC]) from baseline until disease progression. Results The study has completed accrual and 50 pts have been enrolled (mean [range] age: 69.0 (50.0-89.0) years; female: 28 [56.0%]). At screening, 24 (48.0%) pts had a KPS score ≥90, and most pts were at stage ≤II by the International Staging System (ISS; 42, 84.0%) or by the revised ISS (47, 94.0%). Thirty-two (64.0%) pts were refractory to lenalidomide, and 15 (37.5%) had prior ASCT. The median (range) number of study treatment cycles was 9 (1-26). ORR was 50.0% (25 pts); one (2.0%) pt had a complete response, 13 (26.0%) a very good partial response (VGPR), and 11 (22.0%) pts had a PR. The median (range) time from first Dara-Ixa-dex dose until first response (≥PR) is 1.0 (0.9-3.7) month. The median PFS was 8.1 months (95% CI: 5.8-15.6) (Figure). After a median (range) follow-up of 12.4 (0.9-28.4) months, 14 (28.0%) pts are still on treatment; reasons for treatment discontinuation were progressive disease (28 pts, 77.8%), physician's decision and fatal serious adverse event [SAE] (3 pts, 8.3% each), and adverse event [AE] (2pts, 5.6%). Following 15 months of treatment, the median change from baseline for CTX, TRACP-5b, bALP and OC were significant (p Overall, 20 (40.0%) pts have ≥1 grade 3/4 AE, the most common being thrombocytopenia (10 pts, 20.0%), and 14 (28.0%) pts have ≥1 SAE, the most common being acute kidney injury and pneumonia (2 pts [4.0%] each condition). Four fatal SAEs were reported (pneumonia, infection, urinary tract infection, and lower respiratory tract infection). Conclusions Second-line treatment with Dara-Ixa-dex in pts with RRMM who were pre-treated with a lenalidomide-based regimen resulted in rapid ( Figure 1 Figure 1. Disclosures Terpos: Genesis: Consultancy, Honoraria, Research Funding; BMS: Honoraria; Amgen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; GSK: Honoraria, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Research Funding; Novartis: Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding. Gavriatopoulou: Sanofi: Honoraria; Genesis: Honoraria; GSK: Honoraria; Karyopharm: Honoraria; Amgen: Honoraria; Janssen: Honoraria; Takeda: Honoraria. Katodritou: GSK, Amgen, Karyopharm, Abbvie, Janssen-Cilag, Genesis Pharma, Sanofi: Honoraria, Research Funding. Hatjiharissi: Gilead: Honoraria; Genesis: Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Verrou: Karyopharm: Research Funding; Takeda: Honoraria; Genesis: Honoraria; Abbvie: Honoraria, Research Funding; Janssen Cilag: Honoraria, Research Funding; Roche: Honoraria; Amgen: Honoraria. Leonidakis: Health Data Specialists: Current Employment. Delimpasi: Amgen: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Takeda: Honoraria, Speakers Bureau. Symeonidis: MSD: Consultancy, Research Funding; GSK: Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Astellas: Consultancy, Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GenesisPharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi/Genzyme: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Demo: Research Funding; WinMedica: Research Funding. Dimopoulos: Amgen: Honoraria; Janssen: Honoraria; BMS: Honoraria; Beigene: Honoraria; Takeda: Honoraria.

Introduction Systemic immunoglobulin light chain (AL) amyloidosis is a rare disease characterized by amyloid fibril deposits, most commonly in the heart and kidneys. Management of the disease relies primarily on off-label use of multiple myeloma therapies. No treatments are approved for AL amyloidosis in the relapsed/refractory setting. In the phase 3, open-label TOURMALINE-AL1 trial (NCT01659658), patients with relapsed/refractory AL amyloidosis were randomized 1:1 to receive either oral ixazomib plus dexamethasone (Id) or physician's choice (CH) in 28-day cycles, and followed until progression or unacceptable toxicity. An interim analysis demonstrated that Id was well tolerated and, although the primary endpoint of hematologic response rate was not met, time-to-event efficacy analyses consistently favored Id. We report an analysis of patient-reported outcome (PRO) data on health-related quality of life (HRQOL) and AL amyloidosis symptoms from TOURMALINE-AL1; such data for AL amyloidosis in general have been limited. Methods Four PRO instruments were used to collect data to support PRO-related secondary endpoints during the treatment period: the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group Neurotoxicity subscale (FACT/GOG-Ntx), an amyloidosis symptom questionnaire (ASQ), the EuroQoL 5-Dimension 3-Level (EQ-5D-3L), and the Visual Analogue Scale (EQ VAS) were collected at screening, day 1 of each cycle, and end of treatment (EOT), and the 36-item Short Form General Health Survey version 2 (SF-36v2) was collected at screening, day 1 of every third cycle, and EOT. Analysis of PRO data included descriptive summaries of means and change from baseline and a linear mixed model (LMM) for repeated measures for patients in the intent-to-treat (ITT) population with a baseline and at least one postbaseline PRO-specific assessment. No adjustment was made for multiple comparisons. Data cutoff date was 20 February 2019. Results The ITT population included 168 patients (Id: n=85; CH: n=83), who completed up to 58 cycles (Id) and up to 43 cycles (CH); median treatment duration was 11.7 vs 5.0 months, respectively. PRO compliance in the treatment period was high for all instruments (Figure). Baseline HRQOL as measured by the SF-36v2 and EQ VAS was similar between treatment arms. During the treatment period, SF-36v2 Mental and Physical Component Summary (MCS and PCS) scores remained stable relative to baseline and were similar between arms; the 8 subscale scores were also generally maintained over time, and mostly similar between arms. Least-squares (LS) mean changes from baseline were significantly higher (better HRQoL) for Id compared with CH at several cycles in the SF-36v2 Role Physical and Vitality subscales (p Symptom burden as measured by the FACT/GOG-Ntx and ASQ was low at baseline, leaving little room for improvement. FACT/GOG-Ntx scores were generally maintained over time. In the treatment period, there were small but significant differences in LS mean changes from baseline favoring Id over CH at multiple cycles for 7 of the 11 individual items and the neurotoxicity and sensory summary scores; there were small but significant differences favoring CH over Id for 1 individual item (trouble hearing) at a few later cycles. The ASQ total score trended downward slightly (lower burden) during treatment after the first few cycles in both arms. There were significant differences per the LMM favoring Id over CH at cycles 7 and 21 (p In both arms, EQ VAS scores trended upward (better HRQoL) during treatment and then declined slightly at EOT. (LMM analyses were not conducted for EQ-5D.) At EOT, a slight deterioration from baseline was observed in actual scores for SF-36v2 domains and summary scales, FACT/GOG-Ntx neurotoxicity and sensory subscales, and ASQ items and total score for both Id and CH. Conclusions Relapsed/refractory AL amyloidosis patients treated with Id experienced HRQOL and symptoms that were similar to or trended better than patients treated with CH. These data suggest that treatment with Id, although with a substantially longer treatment duration, did not have a negative impact on HRQOL in patients with relapsed/refractory AL amyloidosis, a population with currently no approved treatment options. Figure 1 Figure 1. Disclosures Sanchorawala: Regeneron: Membership on an entity's Board of Directors or advisory committees; Proclara: Membership on an entity's Board of Directors or advisory committees; Oncopeptide: Research Funding; Karyopharm: Research Funding; Sorrento: Research Funding; Pfizer: Honoraria; Caelum: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees; Prothena: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Research Funding; Celgene: Research Funding. Wechalekar: Caelum Biosciences: Other: Clinical Trial Funding; Alexion, AstraZeneca Rare Disease: Consultancy; Janssen: Consultancy; Celgene: Honoraria; Amgen: Research Funding; Takeda: Honoraria. Kim: Janssen, BMS: Research Funding. Schönland: Janssen: Honoraria, Other: Travel grants, Research Funding; Takeda: Honoraria, Other: Travel grants; Sanofi: Research Funding; Prothena: Honoraria, Other: Travel grants; Pfizer: Honoraria. Landau: Takeda, Janssen, Caelum Biosciences, Celgene, Pfizer, Genzyme: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding; Genzyme: Honoraria. Fiona: Pfizer: Research Funding. Suzuki: Janssen: Consultancy, Honoraria; Abie: Honoraria; Sanofi: Honoraria; Novartis: Honoraria; ONO: Honoraria; Takeda: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding. Dispenzieri: Sorrento Therapeutics: Consultancy; Oncopeptides: Consultancy; Pfizer: Research Funding; Alnylam: Research Funding; Janssen: Consultancy, Research Funding; Takeda: Research Funding. Comenzo: Karyopharm: Research Funding; Takeda: Research Funding; Unum: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi-Aventis: Membership on an entity's Board of Directors or advisory committees; Janssen: Patents & Royalties: WO2016187546A1, Research Funding; Prothena Biosciences: Consultancy, Research Funding; Caelum: Consultancy, Research Funding. Cherepanov: Takeda: Current Employment, Current equity holder in publicly-traded company. Hayden: Takeda: Current Employment, Current equity holder in publicly-traded company. Kumar: Takeda: Current Employment, Current holder of stock options in a privately-held company. Labotka: Takeda: Current Employment. Faller: Takeda Pharmaceuticals Co.: Current Employment; Viracta Therapeutics, Inc: Current holder of stock options in a privately-held company, Ended employment in the past 24 months, Membership on an entity's Board of Directors or advisory committees; Briacell, Inc: Current holder of stock options in a privately-held company. Kastritis: Amgen, Genesis Pharma, Janssen, Takeda: Consultancy; Amgen, Janssen, Pfizer: Research Funding; Amgen, Genesis Pharma, Janssen, Takeda, Pfizer: Honoraria.

Background: Two global, randomized, placebo (pbo)-controlled phase 3 studies of single-agent ixazomib (ixa) maintenance therapy are currently ongoing for newly diagnosed MM patients following primary therapy that included autologous stem cell transplantation (ASCT) (MM3, NCT02181413) or excluded ASCT (MM4, NCT02312258). Both trials have demonstrated statistically significant and clinically meaningful improvement in their primary endpoint of progression-free survival (PFS): for MM3, median 26.5 months (mos) ixa vs 21.3 mos pbo (hazard ratio [HR] 0.720, 95% confidence interval [CI] 0.582-0.890, P=0.002); for MM4, median 17.4 mos for ixa vs 9.4 mos for pbo (HR 0.659, 95% CI 0.542-0.801, P Methods: Full methods have previously been reported (Dimopoulos, Lancet 2019; Dimopoulos, J Clin Oncol 2020). Eligible patients (MM3, N=656; MM4, N=706) were randomized 3:2 to receive maintenance therapy with single agent ixa or pbo for a maximum of approximately 24 mos (26 cycles, to the nearest complete cycle) or until progressive disease or unacceptable toxicity, whichever occurred first. Results: At the most recent data cut-off (MM3, 29 January 2021; MM4, 15 October 2020), with median follow up of 64 mos and 36 mos, respectively, 27% (MM3, 174/656) and 29% (MM4, 203/706) of the intention-to-treat (ITT) population had OS events. In MM3, the 5-year Kaplan-Meier estimate for OS was 74% for ixa and 73% for pbo, though the median OS had not yet been reached in either arm (HR 1.008, 95% CI 0.744-1.367, P=0.958; Figure). In MM4, the 5-year Kaplan-Meier OS estimate was 55% for ixa and 56% for pbo, though the median OS had also not yet been reached in either arm (HR 1.136, 95% CI 0.853-1.514, P=0.382; Figure). No new safety signals were identified, and the incidence of new primary malignancies in both studies was similar between ixa and pbo. Conclusions: These most current OS data for MM3 and MM4 have not demonstrated a statistically significant difference for the ixa or the pbo arm to date. After 64 mos of follow-up in MM3, the risk of OS does not differ between the study arms. After 36 mos of follow-up in MM4, the OS HR shows a trend that favors the pbo arm. Because interim analyses of OS may be overrepresented by deaths in patients who did not benefit from maintenance therapy, it is not known to what extent these results will be reflective of the ITT population at the time of the final analyses. As treatment options, including anti-CD38 mAb and other new mechanisms of action, for salvage therapies following progression continue to expand, OS is increasingly being confounded by subsequent therapies. Hence, demonstrating OS advantage for early line MM therapies is becoming increasingly challenging. OS data continue to be collected in these studies for later analyses. Figure 1 Figure 1. Disclosures Dimopoulos: Takeda: Honoraria; Amgen: Honoraria; Beigene: Honoraria; Janssen: Honoraria; BMS: Honoraria. Lonial: AMGEN: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Merck: Honoraria; GlaxoSmithKline: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; BMS/Celgene: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria. Chng: Johnson and Johnson: Honoraria, Research Funding; BMS/Celgene: Honoraria, Research Funding; Takeda: Honoraria; Abbvie: Honoraria; Sanofi: Honoraria; Pfizer: Honoraria. Iida: Takeda: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Chugai: Research Funding; Celgene: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; Daiichi Sankyo: Research Funding; Glaxo SmithKlein: Research Funding; Amgen: Research Funding; Abbvie: Research Funding; Bristol-Myers Squibb: Research Funding. Mateos: Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Regeneron: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bluebird bio: Honoraria; Sea-Gen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene - Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria; Oncopeptides: Honoraria. Morgan: BMS: Membership on an entity's Board of Directors or advisory committees; Jansen: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; GSK: Membership on an entity's Board of Directors or advisory committees. Kumar: Takeda: Current Employment, Current holder of stock options in a privately-held company. Suryanarayan: Takeda: Current Employment. Vorog: Takeda: Current Employment. Fergus: Takeda: Current Employment. Labotka: Takeda: Current Employment. OffLabel Disclosure: Use of the oral proteasome inhibitor ixazomib as maintenance treatment for multiple myeloma following stem cell transplantation or induction therapy in newly diagnosed patients.

Background: IRd has been approved for the treatment of RRMM based on the results of the TOURMALINE-MM1 study, (median progression-free survival [PFS] with IRd vs placebo-Rd: 20.6 vs 14.7 months). Several retrospective and prospective observational studies have shown comparable effectiveness of IRd in ≥2 nd line of therapy (LoT) in the real-world setting to that observed in the MM1 trial, with median PFS ranging from 15.6 to 27.6 months. Here we report an analysis of a large, globally representative dataset pooled from 3 observational studies to investigate the effectiveness of IRd in the overall RRMM population, by LoT, and in subpopulations of pts defined by frailty status. Methods: INSIGHT MM is a large, prospective study which has enrolled >4200 MM pts from Europe, Asia, the US, and Latin America, with a planned follow-up of ≥2 years. UVEA-IXA is a multicenter, longitudinal cohort study of ~300 RRMM pts receiving ixazomib-based treatment via an early access program in Europe. It comprises a retrospective phase (chart review of the period from ixazomib initiation to enrolment in UVEA-IXA) followed by a 1-year prospective follow-up period. REMIX is a retrospective/prospective study of ~200 pts receiving IRd via a compassionate use program in France. The INSURE pooled analysis included adult pts with ≥2 prior MM therapy lines, and who had received IRd in ≥2 nd LoT. PFS was a primary outcome measure; secondary outcome measures included duration of treatment (DoT), overall response rate (ORR), time-to-next therapy (TTNT), overall survival (OS), and safety. Using the Kaplan-Meier method, time-to-event endpoints were analyzed in the overall analysis population, by LoT, and in subpopulations of pts defined by a simplified frailty score (0-1 [non-frail] vs ≥2 [frail]). Adverse events (AEs) and discontinuations/dose reductions due to AEs, were reported separately for each study. Results: In total, 566 pts were identified in this pooled analysis (INSIGHT MM, n=181; UVEA-IXA, n=195; REMIX, n=190), with a median follow-up of 18.5 months overall. Median age at the start of IRd therapy was 68 years (range 36-92), with 21% of pts aged >75 years; 17.6% of pts had an Eastern Cooperative Oncology Group performance status ≥2; pts had received a median of 2 LoT prior to IRd; 41%, 38%, and 21% of pts received IRd as 2 nd, 3 rd, and ≥4 th LoT, respectively. Of 408 pts with frailty scores recorded, 166 (41%) were defined as frail, with similar percentages (39-42%) across all LoTs. Median DoT was 14.0 months overall and decreased with increasing LoT (Table). Median PFS was 20.8 months overall, ranging from 22.1 to 11.6 months with IRd as 2 nd and ≥4 th LoT, respectively (Figure/Table). OS data are not yet mature. Among 406 response-evaluable pts, the ORR was 64.5%, being highest in pts receiving IRd as 2 nd (70.7%) vs 3 rd (63.1%) or ≥4 th LoT (52.1%). In frail vs non-frail pts, median PFS was 11.9 vs 24.0 months, while median DoT was 9.7 vs 16.1 months, respectively; consistent trends for longer DoT/PFS with earlier vs later LoTs were seen in both frail and non-frail pts (Table). Analyses of REMIX AEs are ongoing. In INSIGHT, 30%, 23%, and 18% of pts discontinued ixazomib, lenalidomide, and dexamethasone, respectively, due to AEs; 14%, 19%, and 12% reduced their respective treatment dosage to manage AEs. In UVEA-IXA, discontinuation rates were 17%, 15%, and 10%, respectively; 9%, 9%, and 1%, had dose reductions. The most common AEs leading to ixazomib discontinuation in INSIGHT and UVEA-IXA were thrombocytopenia (19 and 24%, respectively), diarrhea (9 and 18%), infections and infestations/infection (15% and 6%), peripheral neuropathy (7 and 12%), and fatigue in INSIGHT only (11%). Analyses of TTNT, OS, AEs associated with treatment discontinuations in REMIX, and additional analyses of the frail cohort are ongoing and will be presented. Conclusions: The findings from this analysis of a large, global, pooled dataset of 566 pts show that the effectiveness of IRd in routine clinical practice is consistent with the efficacy of IRd observed in TOURMALINE-MM1 (median PFS 20.8 vs 20.6 months), with no new safety concerns. Our results suggest a benefit of treatment with IRd in earlier vs later lines, consistent with reports from previous, smaller real-world studies of IRd in RRMM pts. In addition, this analysis provides important insights on the effectiveness of IRd in frail pts, helping to increase the understanding of the achievable outcomes in this subpopulation. Figure 1 Figure 1. Disclosures Leleu: Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Carsgen Therapeutics Ltd: Honoraria; Pierre Fabre: Honoraria; Amgen: Honoraria; Gilead Sciences: Honoraria; Janssen-Cilag: Honoraria; Karyopharm Therapeutics: Honoraria; Mundipharma: Honoraria; Merck: Honoraria; Novartis: Honoraria; Oncopeptides: Honoraria; AbbVie: Honoraria; Roche: Honoraria; Sanofi: Honoraria; Takeda: Honoraria, Other: Non-financial support. Boccadoro: Sanofi: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Mundipharma: Research Funding; AbbVie: Honoraria; GSK: Membership on an entity's Board of Directors or advisory committees. Lee: Sanofi: Consultancy; Karyopharm: Consultancy; Oncopetides: Consultancy; Takeda Pharmaceuticals: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Regeneron: Research Funding; Janssen: Consultancy, Research Funding; Celgene: Consultancy; Genentech: Consultancy; GlaxoSmithKline: Consultancy, Research Funding; Legend Biotech: Consultancy; Bristol Myers Squibb: Consultancy. Zonder: Intellia: Consultancy; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Regeneron: Consultancy; Caelum Biosciences: Consultancy; Amgen: Consultancy; BMS: Consultancy, Research Funding; Janssen: Consultancy; Alnylam: Consultancy. Macro: Takeda: Honoraria, Other: Travel accomodation, Research Funding; Janssen: Honoraria, Other: Travel accomodation, Research Funding; GSK: Honoraria; Sanofi: Honoraria; Celgen/BMS: Honoraria. Ramasamy: Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Conference registration, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Conference registration, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Conference registration, Research Funding; Celgene (BMS): Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Conference registration, Research Funding; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive biotech: Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer oncology: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees. Hulin: abbvie: Honoraria; Janssen: Honoraria; Celgene/BMS: Honoraria; Takeda: Honoraria; Sanofi: Honoraria. Ren: Takeda: Current Employment. Bent-Ennakhil: Takeda: Current Employment. Bouillie: TAKEDA ONCOLOGIE FRANCE: Current Employment. Cherepanov: Takeda: Current Employment, Current equity holder in publicly-traded company. Stull: Takeda Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Terpos: Amgen: Consultancy, Honoraria, Research Funding; BMS: Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Genesis: Consultancy, Honoraria, Research Funding; GSK: Honoraria, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Research Funding; Novartis: Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding.

Introduction: A number of cytogenetic abnormalities (CAs) are associated with poorer prognosis in MM, including del(17p), t(4;14), t(14;16), and amp1q21. There is a general consensus that treatment with proteasome inhibitors (PIs) benefits pts carrying these CAs (Sonneveld Blood 2016). This meta-analysis of four phase 3 studies assesses PFS benefit in pts receiving the oral PI ixa vs pbo regarding the specific adverse CAs. Methods: Pts in TOURMALINE-MM1 (N=722; relapsed/refractory MM; Moreau N Engl J Med 2016) and MM2 (N=705; newly diagnosed MM; Facon Blood 2021) received ixa plus lenalidomide-dexamethasone (Rd) vs pbo-Rd (1:1). Pts in TOURMALINE-MM3 (N=656; Dimopoulos Lancet 2019) and TOURMALINE-MM4 (N=706; Dimopoulos J Clin Oncol 2020) received ixa vs pbo (3:2) as maintenance following autologous stem cell transplant or as post-induction maintenance in transplant-ineligible pts, respectively. In TOURMALINE-MM1/MM2, CAs were centrally assessed on CD138 positive sorted cells from bone marrow samples collected at study entry using fluorescence in situ hybridization (FISH). Cutoff values for defining the presence of del(17p), t(4;14), and t(14;16) were 5%, 3%, and 3% positive cells, respectively, based on the false-positive rates (technical cutoffs) of the FISH probes used, and cutoff values of 3% (MM1) and 20% (MM2) were used for amp1q21. In TOURMALINE-MM3/MM4, cytogenetic assessment was performed locally using FISH or conventional karyotyping with locally defined thresholds for positivity. Results: 270/1227 (22%) vs 227/1019 (22%) evaluable pts receiving ixa-based vs pbo-based therapy had high-risk CAs [del(17p), t(4;14), t(14;16)]: 75 vs 62 in MM1, 60 vs 63 in MM2, 61 vs 54 in MM3, and 74 vs 48 in MM4. 957/1227 (78%) vs 792/1019 (78%) had complementary standard-risk CAs: 200 vs 216 in MM1, 231 vs 234 in MM2, 252 vs 152 in MM3, and 275 vs 190 in MM4. 555/1142 (49%) vs 479/955 (50%) evaluable pts receiving ixa-based vs pbo-based therapy had expanded high-risk CAs (high-risk CAs ± amp1q21): 155 vs 154 in MM1, 134 vs 146 in MM2, 116 vs 88 in MM3, and 150 vs 91 in MM4. 587/1142 (51%) vs 476/955 (50%) had complementary standard-risk CAs: 122 vs 126 in MM1, 164 vs 153 in MM2, 154 vs 89 in MM3, and 148 vs 108 in MM4. After a median follow-up in the pooled analysis of 25.6 months (mos; 12.7, 54.6, 29.7, and 21.3 mos in MM1, MM2, MM3, and MM4, respectively), the hazard ratio (HR) for PFS with ixa-based vs pbo-based therapy in pts with high-risk CAs was 0.74 (95% confidence interval [CI] 0.59-0.93; median 17.8 vs 13.2 mos) and 0.70, (95% CI 0.62-0.80; median 26.3 vs 17.6 mos) in pts with standard-risk CAs. In the subgroup analyses of expanded high-risk CAs, the HR for PFS with ixa-based vs pbo-based therapy in pts in the expanded high-risk group was 0.75 (95% CI 0.64-0.87; median 18.1 vs 14.1 mos; Figure 1) and 0.71 (95% CI 0.59-0.85; median 36.1 vs 21.4 mos) in the complementary standard-risk group. Analyses of PFS according to the presence of individual CAs (Figure 2) indicated differing magnitudes of PFS benefit. Notably, in pts with t(4;14) (n=124 vs n=102), the HR for PFS with ixa-based vs pbo-based therapy was 0.68 (95% CI 0.48-0.96; median 22.4 vs 13.2 mos), while for pts with amp1q21 (n=380 vs n=312), the HR was 0.77 (95% CI 0.63-0.93; median 18.8 vs 14.5 mos) and for pts with del(17p) (n=141 vs n=107) the HR was 0.80 (95% CI 0.59-1.09; median 15.7 vs 13.2 mos). Conclusions: This pooled analysis demonstrated a PFS benefit with ixa-based therapy vs pbo-based therapy regardless of the presence of specific adverse CAs, with a similar magnitude of benefit in pts with (expanded) high-risk CAs and the respective complementary standard-risk groups. However, due to the differences in study eligibility criteria and pt populations, ixa combined with Rd or as single-agent maintenance therapy may not abrogate the negative impact of high-risk CAs. Analyses of PFS in subgroups with specific CAs indicated that the greatest magnitudes of benefit (lowest HRs) with ixa-based vs pbo-based therapy were in pts with t(4;14) (HR 0.68) and pts with amp1q21 (HR 0.77), suggesting that the improved outcome with ixa-based vs pbo-based therapy in the expanded high-risk subgroup was primarily driven by PFS differences in pts with these more common CAs. Further study is needed, and additional sensitivity analyses will be presented in subsequent publications. Figure 1 Figure 1. Disclosures Chng: BMS/Celgene: Honoraria, Research Funding; Amgen: Honoraria; Takeda: Honoraria; Abbvie: Honoraria; Sanofi: Honoraria; Pfizer: Honoraria; Johnson and Johnson: Honoraria, Research Funding. Lonial: BMS/Celgene: Consultancy, Honoraria, Research Funding; AMGEN: Consultancy, Honoraria; GlaxoSmithKline: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria. Morgan: Takeda: Honoraria. Iida: Amgen: Research Funding; Daiichi Sankyo: Research Funding; Glaxo SmithKlein: Research Funding; Ono: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Chugai: Research Funding; Abbvie: Research Funding; Janssen: Honoraria, Research Funding; Bristol-Myers Squibb: Research Funding. Moreau: Sanofi: Honoraria; Celgene BMS: Honoraria; Abbvie: Honoraria; Amgen: Honoraria; Janssen: Honoraria; Oncopeptides: Honoraria. Kumar: Bluebird Bio: Consultancy; Carsgen: Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Antengene: Consultancy, Honoraria; Novartis: Research Funding; Oncopeptides: Consultancy; Tenebio: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche-Genentech: Consultancy, Research Funding; Beigene: Consultancy; Merck: Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding. Twumasi-Ankrah: Takeda: Current Employment. Kumar: Takeda: Current Employment, Current holder of stock options in a privately-held company. Dash: Takeda: Current Employment, Current equity holder in publicly-traded company. Vorog: Takeda: Current Employment. Zhang: Takeda: Current Employment. Suryanarayan: Takeda: Current Employment. Labotka: Takeda: Current Employment. Dimopoulos: Janssen: Honoraria; Takeda: Honoraria; Beigene: Honoraria; BMS: Honoraria; Amgen: Honoraria. OffLabel Disclosure: Use of the oral proteasome inhibitor ixazomib for the initial treatment of multiple myeloma and as maintenance treatment following stem cell transplantation or induction therapy in newly diagnosed patients

Backrground: Several randomized controlled clinical trials have demonstrated improved outcomes for newly diagnosed multiple myeloma (NDMM) patients who were treated with lenalidomide as maintenance therapy after autologous stem cell transplant (ASCT). Proteasome inhibitors have demonstrated clinical benefit in myeloma patients when used as part of induction and maintenance regimens, and the combination of proteasome inhibitors and lenalidomide in induction regimens has produced strong clinical responses. In this study, the addition of ixazomib to lenalidomide maintenance post-ASCT in NDMM patients was evaluated. Methods: Patients (n=64) were started on maintenance therapy with lenalidomide and ixazomib within 60-180 days of stem cell infusion. Each cycle was defined as 28 days with lenalidomide starting at 10 mg/day orally for 28 days with the option to increase the dose to 15 mg after 3 cycles. Ixazomib was provided at 3 mg (n=48 patients) or 4 mg (n=16 patients) orally on days 1, 8, and 15 of each 28-day cycle. However, ixazomib dose was reduced to 3 mg in all patients based on toxicity observed in other clinical trials of ixazomib at that time. The primary endpoint measured was progression-free survival (PFS), which was defined as the time between ASCT and disease progression or death, whichever occurred first. Results: A total of 64 patients were enrolled on this study between December 4, 2012, and May 13, 2015. Of these patients, 41 (64.06%) were 60 years of age or older and 42 (65.63%) were male. Fourteen patients had high-risk cytogenetic features (+1q21, Del17p, t(14:16), t(4:14)), 50 patients had standard cytogenetic risk features (t(11:14), t(6:14), hyperdiploidy, normal) and 9 patients had International Staging System stage 3 disease. Median PFS (mPFS) for all patients was 73.3 months and has not been reached for those with ISS stage 1 disease. mPFS for ISS Stage 3 disease and high-risk cytogenetic subgroups was 33.8 and 25.4 months, respectively. Twenty-two patients had progressive disease, while 21 patients continue to receive dual maintenance. Response rates deepened over time from baseline post-ASCT for 39 patients. The complete response (CR)/stringent CR rate was 42.9% and median overall survival was not reached with a median follow-up of 62 months (range 25.4 - 82.1 months). Thirty-one patients (48%) had improvement from their baseline response after maintenance therapy: 6 patients improved from PR to VGPR; 7 from PR to stringent CR (sCR)/CR; 16 from VGPR to sCR/CR; 1 from SD to CR; and 1 patient improved from SD to VGPR. The median time to response in the 31 patients with improved response to maintenance therapy was 10.9 months (range, 0.9 to 51.3 months). Minimal residual disease (MRD) was evaluated by multicolor flow cytometry (10^-5) in 21 patients by bone marrow biopsy; 8 patients were MRD-positive. The most common grade 3/4 adverse events (AEs) included neutropenia (46.9%), leukopenia (20.3%), thrombocytopenia (15.6%), lung infections (26.6%), diarrhea and maculopapular rash (12.5% each). Secondary primary malignancies occurred in 9 patients; these included squamous cell carcinoma of the skin (n=4), basal cell carcinoma of the skin (n=1), squamous cell carcinoma and basal cell carcinoma of the skin (n=1), hepatocellular carcinoma (n=1), melanoma (n=1) and leukemia (n=1). AEs led to dose reductions in ixazomib and lenalidomide in 20 and 31 patients, respectively. Discontinuation of ixazomib due to AEs occurred in 4 patients. Grade 1/2 neuropathy occurred in 22 patients and led to reduction or discontinuation of ixazomib in 2 patients. Conclusion: Addition of ixazomib to lenalidomide maintenance in myeloma patients demonstrated a better than expected PFS compared with what has been reported in studies of lenalidomide alone, and was both safe and tolerable. These results indicate a significant clinical benefit, especially for standard risk patients. Figure 1 Figure 1. Disclosures Patel: Oncopeptides: Consultancy; Pfizer: Consultancy; Janssen: Consultancy, Research Funding; BMS Celgene: Consultancy, Research Funding. Shah: Karyopharm Therapeutics Inc.: Current Employment, Current equity holder in publicly-traded company. Lee: GlaxoSmithKline: Consultancy, Research Funding; Bristol Myers Squibb: Consultancy; Celgene: Consultancy; Regeneron: Research Funding; Takeda Pharmaceuticals: Consultancy, Research Funding; Oncopetides: Consultancy; Amgen: Consultancy, Research Funding; Karyopharm: Consultancy; Legend Biotech: Consultancy; Sanofi: Consultancy; Janssen: Consultancy, Research Funding; Genentech: Consultancy. Thomas: BeiGene: Membership on an entity's Board of Directors or advisory committees; BMS: Research Funding; Ascentage Pharma: Research Funding; X4 Pharma: Research Funding; Genentech: Research Funding; Acerta Pharma: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees. Qazilbash: NexImmune: Research Funding; Angiocrine: Research Funding; Amgen: Research Funding; Bristol-Myers Squibb: Other: Advisory Board; Oncopeptides: Other: Advisory Board; Janssen: Research Funding; Biolline: Research Funding. Orlowski: Amgen, Inc., BioTheryX, Inc., Bristol-Myers Squibb, Celgene, EcoR1 Capital LLC, Genzyme, GSK Biologicals, Janssen Biotech, Karyopharm Therapeutics, Inc., Neoleukin Corporation, Oncopeptides AB, Regeneron Pharmaceuticals, Inc., Sanofi-Aventis, and Takeda P: Consultancy, Honoraria; Asylia Therapeutics, Inc., BioTheryX, Inc., and Heidelberg Pharma, AG.: Other: Laboratory research funding; CARsgen Therapeutics, Celgene, Exelixis, Janssen Biotech, Sanofi-Aventis, Takeda Pharmaceuticals North America, Inc.: Other: Clinical research funding; Asylia Therapeutics, Inc.: Current holder of individual stocks in a privately-held company, Patents & Royalties; Amgen, Inc., BioTheryX, Inc., Bristol-Myers Squibb, Celgene, Forma Therapeutics, Genzyme, GSK Biologicals, Janssen Biotech, Juno Therapeutics, Karyopharm Therapeutics, Inc., Kite Pharma, Neoleukin Corporation, Oncopeptides AB, Regeneron Pharmaceuticals, I: Membership on an entity's Board of Directors or advisory committees.

Introduction: Ixazomib is an oral proteasome inhibitor (PI) that is currently approved to be administered once weekly in combination with lenalidomide (LEN) and dexamethasone in RRMM (Moreau et al N Eng J Med 2016; 374:1621-1634). As most patients are LEN refractory at the time of first relapse, pomalidomide-based regimens are commonly utilized due to their proven efficacy in this population. We hypothesized that twice weekly dosing of ixazomib may be more efficacious as this has been previously studied as monotherapy (Richardson et al, Blood 2014 Aug 14;124(7):1038-46) and in combination with LEN demonstrating promising activity and safety (Richardson et al, Br J Haematol. 2018 Jul;182(2):231-244). We present results of our phase I/II trial of twice weekly ixazomib in combination with pomalidomide and dexamethasone in RRMM, including the recommended phase II dose and first report of efficacy of this combination. Methods: This is a phase I/II multicenter, single-arm, open label study evaluating the combination of twice weekly ixazomib with pomalidomide and dexamethasone in RRMM. The primary objective for phase I portion is to determine safety and the maximum tolerated dose (MTD) of this combination using a standard 3+3 dose escalation design and primary objective of the phase II portion is overall response rate (ORR) with secondary outcomes including progression-free survival (PFS) and clinical benefit rate (CBR) Ixazomib is studied at doses of 3mg or 4mg on days 1, 4, 8, 11, pomalidomide at a dose of 2mg, 3mg and 4mg on days 1-14 and dexamethasone is administered at a dose of 12mg on days 1, 2, 4, 5, 8, 9, 11, 12 (8mg for patients > 75 years old) on a 21 day cycle (Table 1). Patients were included if they received 2 prior lines of therapy, but 1 prior line was allowed if first line treatment included a PI and an immunomodulatory agent and disease relapse occurred within 60 days of last therapy. Patients who were ixazomib exposed or pomalidomide refractory were excluded. Results: At the time of data cutoff, 22 patients have been enrolled across all cohorts. There were two dose-limiting toxicities (DLT) noted during the dose escalation phase (upper respiratory infection and neutropenia, respectively) establishing the RP2D of 4mg ixazomib and 4mg pomalidomide. Median age at the time of enrollment was 68 years old with ISS stage at diagnosis of I (14%), II (32%), and III (23%). High-risk FISH abnormalities were seen in 43% of patients as follows: del 17p (9%), gain 1q (36%), t(4;14) (5%), t(14;16) (9%). Median prior lines of therapy was 2 (range 1-4) with 100% of patients having prior treatment with lenalidomide and 95% with prior bortezomib. Fifty-nine percent of patients had a prior autologous stem cell transplant. Ten patients have been enrolled at the RP2D at the time of data cut off. The most common treatment-related toxicities were mainly low grade (Grade 1-2) and included neutropenia (45%), lower extremity edema (41%), insomnia (36%), dyspnea (32%) and weight gain (32%). Grade 3 or greater toxicities were noted in 36% of patients and included neutropenia (18%), thrombocytopenia (5%), anemia (5%), atrial fibrillation (5%), dehydration (5%), diarrhea (5%), fall (5%), lung infection (5%), and pneumonitis (5%). Dose reductions occurred in 13 patients and predominantly involved dexamethasone due to weight gain, insomnia, atrial fibrillation and fatigue. There have been no discontinuations due to toxicity and no treatment related mortality at the time of data cutoff. The ORR in all cohorts was 45%, with 9% achieving sCR, 9% VGPR and 86% achieving stable disease or better. At the RP2D, the ORR was 50% with 30% of patients achieving VGPR or better. At the median follow up of 10 months, median PFS was 13 months (95% CI: 11-NR) and median overall survival was not reached. Conclusions: Twice weekly ixazomib in combination with pomalidomide and dexamethasone is a generally well-tolerated regimen with promising activity. The recommended phase II dose has been established at 4mg of ixazomib and 4mg of pomalidomide demonstrating efficacy in a high-risk cohort of RRMM patients. The all-oral nature of this regimen has allowed for robust accrual during the COVID 19 pandemic. Figure 1 Figure 1. Disclosures Nadeem: BMS: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; GSK: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Membership on an entity's Board of Directors or advisory committees. Mo: Karyopharm: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees; Epizyme: Consultancy; Eli Lilly: Consultancy; BMS: Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVIE: Consultancy. Bianchi: Jacob D. Fuchsberg Law Firm: Consultancy; MJH: Honoraria; Karyopharm: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria. Sanchorawala: Celgene: Research Funding; Pfizer: Honoraria; Sorrento: Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Research Funding; Prothena: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees; Caelum: Membership on an entity's Board of Directors or advisory committees, Research Funding; Regeneron: Membership on an entity's Board of Directors or advisory committees; Proclara: Membership on an entity's Board of Directors or advisory committees; Oncopeptide: Research Funding; Karyopharm: Research Funding. Sperling: Adaptive: Consultancy. Munshi: Janssen: Consultancy; Takeda: Consultancy; Bristol-Myers Squibb: Consultancy; Celgene: Consultancy; Amgen: Consultancy; Karyopharm: Consultancy; Oncopep: Consultancy, Current equity holder in publicly-traded company, Other: scientific founder, Patents & Royalties; Legend: Consultancy; Abbvie: Consultancy; Adaptive Biotechnology: Consultancy; Novartis: Consultancy; Pfizer: Consultancy. Ghobrial: AbbVie, Adaptive, Aptitude Health, BMS, Cellectar, Curio Science, Genetch, Janssen, Janssen Central American and Caribbean, Karyopharm, Medscape, Oncopeptides, Sanofi, Takeda, The Binding Site, GNS, GSK: Consultancy. Anderson: Sanofi-Aventis: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Millenium-Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Scientific Founder of Oncopep and C4 Therapeutics: Current equity holder in publicly-traded company, Current holder of individual stocks in a privately-held company; Mana Therapeutics: Membership on an entity's Board of Directors or advisory committees. Richardson: AbbVie: Consultancy; Karyopharm: Consultancy, Research Funding; Janssen: Consultancy; Protocol Intelligence: Consultancy; Takeda: Consultancy, Research Funding; GlaxoSmithKline: Consultancy; Regeneron: Consultancy; Secura Bio: Consultancy; Sanofi: Consultancy; AstraZeneca: Consultancy; Celgene/BMS: Consultancy, Research Funding; Oncopeptides: Consultancy, Research Funding; Jazz Pharmaceuticals: Consultancy, Research Funding.

Background The Phase III TOURMALINE-MM4 Trial demonstrated that the oral proteasome inhibitor, Ixazomib maintenance significantly improved progression-free survival (PFS) in patients with newly diagnosed multiple myeloma (NDMM) not undergoing ASCT. However, patient recruitment for clinical trials is highly selective so the extent to which study populations represent real-world patients is unclear. Currently, data validating the use of ixazomib maintenance in clinical practice in Chinese landscape is scarce. Methods we conducted a retrospective, observational study of NDMM patients meeting International Myeloma Working Group (IMWG) criteria, who received ixazomib-based maintenance therapy. Data was collected from 26 medical centers in southern China. Enrollment was stratified by risk stage, transplant status and maintenance regimens. The characteristics, toxicities and survival outcomes were recorded. Results We included 105 NDMM patients who received ixazomib-based maintenance treatment. Mean age at diagnosis was 59.82 ± 9.80 years, with 62.9% male patients. MM International Staging System (ISS), stage 3 was the most common with 49.04% of patients; 62.86% had an Eastern Cooperative Oncology Group performance score ≥2, and 81.9% with concomitant diseases. By the end of over 70 months follow-up since initial diagnosis, median PFS was 69.45 (95%CI: 31.42-107.48) months, and median OS was not achieved yet. We explored potential influencing factors of progression at the post-maintenance evaluation with a crude model using logistic regression. Difference in PFS was not statistically significant by status at pre-maintenance response, transplantation, maintenance therapy regimens (single/two/three-agent) and dexamethasone in maintenance regimens (p >0.05). Eight patients (7.62%) had grade≥3 treatment-emergent adverse events (TEAEs); 5.7% discontinued treatment because of TEAEs. Common any-grade TEAEs included fatigue (18.1%), diarrhea (16.19%), and peripheral neuropathy (11.43%). Conclusion Although there are certain differences in maintenance treatment options for newly diagnosed multiple myeloma patients in real-world practice, the results of our retrospective study support that the ixazomib-based maintenance therapy was effective with acceptable toxicity and single-agent ixazomib maintenance provided enough clinical benefit compared to two or three agents. Keywords: multiple myeloma, ixazomib, maintenance therapy, real-world practice Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Background Maintenance therapy is considered a standard of care in transplant eligible (TE) and non transplant eligible (NTE) patients with newly diagnosed multiple myeloma (NDMM). While immunomodulators (IMID) and proteasome inhibitors (PI) have been proposed as maintenance therapy options, there are no randomised trials (RCTs) directly comparing these agents in the maintenance setting. The IMID lenalidomide (Len) and the PI ixazomib (Ixa) have been compared against placebo as maintenance strategies in NDMM. We present a network meta-analysis (NMA) of RCTs comparing the efficacy and safety of Len and Ixa maintenance therapies in NDMM. Methods We searched various biomedical databases for eligible studies evaluating Len or Ixa against placebo/ observation as maintenance therapy in patients with NDMM from date of inception through November 2020. The primary outcome was progression-free survival (PFS). Secondary outcomes include overall survival (OS) and adverse events (AE). The Cochrane risk of bias tool version 2.0 was used to assess trial quality. A Bayesian NMA model was used to assess the relative effects of competing treatments on PFS and OS outcomes. Adverse events were assessed using the synthesis without meta-analysis (SWIM) approach due to variability in the toxicity scoring criteria. The GRADE approach was used to rate the certainty of the evidence. This study is registered with PROSPERO, CRD42021226157. Results We identified eight studies including 3229 transplant eligible (TE) and 1689 non transplant eligible (NTE) patients. All studies were judged to have low risk of bias. Len but not Ixa was associated with statistically significant improvement in PFS when compared to placebo in TE (Len: Hazard Ratio (HR) 0.46, 95% Credible Interval (CrI) 0.35-0.56, high certainty; Ixa: HR 0.72, 95% CrI 0.46-1.13, moderate certainty) and NTE (Len: HR 0.46, 95% CrI 0.29-0.75, high certainty; Ixa: HR 0.69, 95% CrI 0.43-1.18, moderate certainty). Bayesian modelling demonstrated a 97% and 93% probability that Len resulted in superior PFS compared to Ixa in TE and NTE patients respectively. Both Len and Ixa were not associated with statistically significant improvement in OS compared to placebo in TE and NTE patients. There was no significant effect modification on the effect of Len vs placebo and Ixa vs placebo by cytogenetics status, use of proteasome inhibitors for induction or duration of maintenance therapies for PFS and/or OS outcomes. Len were judged to have a higher incidence of second malignancies and grade 3 or 4 neutropenia than Ixa while Ixa was judged to have a higher incidence of thrombocytopenia than Len. Conclusions Maintenance therapy with Len may provide a larger PFS benefit than Ixa regardless of type of induction therapy and cytogenetic risk in patients with NDDM. The differing toxicity profile of these agents is also an important consideration for treatment decisions. RCTs directly comparing these maintenance strategies are warranted. Figure 1 Figure 1. Disclosures Ooi: Jansen: Honoraria; Teva Pharmaceuticals: Honoraria; GSK: Honoraria; Abbvie: Honoraria; Amgen: Honoraria. Chng: Sanofi: Honoraria; Abbvie: Honoraria; Takeda: Honoraria; Amgen: Honoraria; BMS/Celgene: Honoraria, Research Funding; Johnson and Johnson: Honoraria, Research Funding; Pfizer: Honoraria.

Background: The addition of ixazomib to the doublet lenalidomide and dexamethasone (RD) in relapsed and refractory multiple myeloma (RRMM) has shown significant benefit in progression free survival (PFS) in the TOURMALINE-MM1 study. Several real-world data including our previous analysis confirmed that the combination IRD is feasible and with fair outcomes even outside the clinical trial. Here we report an updated analysis which is aimed at overall survival (OS) and the PFS2 interval which is defined as the time from the date of treatment initiation to the date of first documentation of progressive disease after initiation of further anti-myeloma treatment or death from any cause. Methods: We analyzed a cohort of 344 patients with RRMM, 127 being treated by IRD and 217 by RD combination. The group characteristics and study design are described elsewhere. 1 The median follow-up of the whole cohort was 28.5 months. The primary endpoint was OS, OS in patients with relapse 1-3, progression free survival (PFS), and PFS2. Secondary endpoints were response rates and toxicity profile. For statistical analysis we used Fisher's exact test or Mann-Whitney U test. Survival measures were assessed using the Kaplan-Meier methodology, and statistical significance was assessed using the log-rank test at a significance level of α = 0.05 (all tests two-sided). Results: The outcomes of OS in the whole cohort were already published before, with significantly longer median OS in the IRD vs RD cohort (mOS 36.6 months vs 26.0 months, p = 0.008).1 In the follow-up analysis, the medians were slightly improved, maintaining a significant difference (mOS 40.9 vs 27.1 months, p = 0.001). In patients treated within relapse 1-3, the results outcomes were even more pronounced (mOS 51.7 vs 27.8 months, p ˂ 0.001). The median PFS was also better in the IRD cohort (mPFS 17.5 vs 12.5 months, p = 0.013) but the results did not substantially differ from our previous analysis. The median PFS2 in the IRD vs RD cohort was significantly longer in the IRD cohort (mPFS2 29.8 vs 21.6 months, p = 0.016). The subsequent therapy included mostly pomalidomide (27.5% vs 30.8%), bortezomib (28.8% vs 28.2%) or thalidomide (10.0% vs 16.2%). Monoclonal antibodies (daratumumab, isatuximab) were more frequently used after IRD combination (21.3% vs 4.3%). The response rates in the IRD vs RD cohort were similar as in our primary analysis: overall response rate (ORR) 73.0% vs 66.8%, with significant difference in very good partial response and better (VGPR+) 38.1% vs 26.3%. The toxicity profile did not reveal any additional safety concerns. Majority of grade 3+ toxicities included hematological toxicity (anemia, neutropenia, thrombocytopenia) and infections, with similar distribution in the cohorts. Conclusion: The treatment of RRMM using the full oral IRD regimen in routine clinical practice is easy, safe and with significantly improved outcomes in comparison to RD doublet. Our follow-up analysis confirmed the impact on OS in patients in the whole cohort including relapse 1-3. The median PFS2 was also longer in the IRD cohort, possibly affected by more frequent use of monoclonal antibodies in the next treatment. With support of AZV 17-29343A, NV18-03-00500, MH CZ - DRO (FNOl, 00098892), IGA-LF-2021-001. 1) Minarik J, Pika T, Radocha J. et al. Survival benefit of ixazomib, lenalidomide and dexamethasone (IRD) over lenalidomide and dexamethasone (Rd) in relapsed and refractory multiple myeloma patients in routine clinical practice. BMC Cancer 2021; 21: https://doi.org/10.1186/s12885-020-07732-1 Disclosures Minarik: Amgen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria. Hajek: Novartis: Consultancy, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Pharma MAR: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Introduction Induction therapy followed by autologous stem cell transplantation (ASCT) before maintenance is the standard of care for transplant eligible NDMM patients. The addition of daratumumab to bortezomib, thalidomide, and dexamethasone (VTD) improved response rates and reduced the risk of progression or death compared to VTD alone (Moreau et al, Lancet 2019). Other quadruplet combinations such as carfilzomib, lenalidomide, dexamethasone and daratumumab have also been evaluated, showing high response rates and high levels of MRD negativity (Landgren et al, JAMA Oncol 2021), which seems particularly suitable to high-risk patients. The replacement of bortezomib with ixazomib in an all-oral combination with lenalidomide and dexamethasone (IRD) has been demonstrated to be safe, convenient, and effective in induction and consolidation before and after ASCT (Moreau et al, Blood 2017). The more progressive response kinetics and the very safe profile of ixazomib led to consider daratumumab plus IRD (D-IRD) extended induction and consolidation in standard-risk NDMM patients. We evaluated its safety and efficacy before and after ASCT followed by lenalidomide maintenance as frontline therapy for patients with standard-risk NDMM younger than 66 years (NCT03669445). Methods Patients with standard-risk cytogenetic MM (defined by FISH at diagnosis according to IMWG criteria) received six 21 days-cycles of induction therapy with daratumumab 16 mg/Kg IV at days 1, 8, 15 (cycles 1-4) and days 1 and 15 (cycles 5-6) plus ixazomib 3 mg on days 1, 4, 8 and 11 plus lenalidomide 25 mg on days 1 through 14 and dexamethasone 40 mg on days 1, 8 and 15. Peripheral blood stem cells were collected after cyclophosphamide mobilization, followed by Melphalan 200 mg/m2 and ASCT. D-IRD consolidation started 2 to 3 months after ASCT and consisted in four 28 days-cycles with daratumumab at days 1 and 15, ixazomib 4 mg on days 1, 8 and 15, lenalidomide 25 mg on days 1 to 21 and dexamethasone 20 mg on days 1, 8, 15 and 22 (cycles 7-8) and days 1 and 15 (cycles 9-10). Single agent lenalidomide maintenance was administrated at 10 mg on days 1 through 21 of a 28 days-cycle during 26 cycles. The primary endpoint was the MRD-negativity after consolidation and before maintenance. MRD-negativity was assessed using NGS method with a sensitivity threshold of detection of MM cells up to 10 -6. Secondary objectives were toxicity according to NCI-CTCAE version 5.0, MRD-negativity rates at other timepoints, response rates according to 2016 IMWG criteria as well as PFS, TTP and OS. Results From 12/2018 to 09/2019, 45 patients were enrolled in 10 IFM centers. Median age was 57 years [28-65] and 66.7% were male. Since it was an eligibility criteria, there was no t(4;14), t(14;16) or del(17p). The distribution of ISS scores 1, 2 and 3 was as follows: 40.9%, 38.6% and 20.5%. On 45 patients who initiated the treatment, 43 completed induction, ASCT and consolidation and 42 started maintenance. All patients responded (ORR 100% [CI 92.1-100.0]) and the best response was sCR or CR in 53.4%, VGPR in 40% and PR in 6.7% of the patients. For the primary endpoint 38 patients were evaluable at 10 -6 after consolidation and the MRD-negativity rate was 39.5% ([CI 26.1-54.1]; p=0.137). At a sensitivity of 10 -5 (IMWG criteria) the MRD negativity rate was 51.4% ([CI 36.8-65.7]; p=0.005). Response rates deepen with time, regarding IMWG categories as well as MRD-negativity rates (Figure). After a median follow up of 23.6 months, 2 patients experienced disease progression. The PFS rate at 24 months was 95.2% [CI 82.1-98.8]. Serious adverse events occurred in 15 (33.3%) patients and grade 3/4 event in 28 (62.2%). The most common grade 3-4 toxicities were neutropenia (28.9%), thrombocytopenia (11.1%) and infections (15.6%). Moderate peripheral neuropathy (35.6%; no grade 3-4), gastrointestinal disorders (4.4% grade 3-4) and rash (28.9%; no grade 3-4) were also described. No deaths or secondary primary malignancies were reported to date. Conclusion D-IRD as extended induction prior to, and as consolidation following ASCT was safe and allows gradually deepening responses in standard-risk MM, with 39.5% of patients with MRD negativity at 10 -6 after consolidation, 2-year PFS at 95.2% and 2-year OS at 100%. MRD-negativity rates are lower than those obtained with D-VTD or D-KRD; more follow-up is needed to confirm PFS and OS data. Figure 1 Figure 1. Disclosures Perrot: Abbvie: Honoraria; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Decaux: Amgen BMS Celgene Janssen Sanofi Takeda: Honoraria. Hulin: Janssen: Honoraria; Takeda: Honoraria; Sanofi: Honoraria; Celgene/BMS: Honoraria; abbvie: Honoraria. Macro: Janssen: Honoraria, Other: Travel accomodation, Research Funding; GSK: Honoraria; Sanofi: Honoraria; Celgen/BMS: Honoraria; Takeda: Honoraria, Other: Travel accomodation, Research Funding. Karlin: Abbvie: Honoraria; Takeda: Honoraria, Other: member of advisory board; Celgene-BMS: Honoraria, Other: member of advisory board; Sanofi: Honoraria; GSK: Honoraria, Other: member of advisory board; Amgen: Honoraria, Other: travel support and advisory board ; Janssen: Honoraria, Other: member of advisory board, travel support; oncopeptide: Honoraria. Roussel: Janssen: Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria; BMS: Honoraria; Takeda: Consultancy; Amgen: Consultancy. Guillemot: Takeda: Honoraria. Avet-Loiseau: Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees. Moreau: Janssen: Honoraria; Amgen: Honoraria; Celgene BMS: Honoraria; Abbvie: Honoraria; Sanofi: Honoraria; Oncopeptides: Honoraria. OffLabel Disclosure: The quadruplet Dara-Ixa-Len-Dex is not approved in newly diagnosed multiple myeloma.

Introduction: Depth of response is associated with long-term outcomes in multiple myeloma (MM); however, the effect of response kinetics on outcomes in NDMM is variable and less clear. Although some studies have shown that achieving a ≥very good partial response (VGPR) at 4 months (mos) from diagnosis is associated with increased overall survival (Garderet Leukemia 2018), other reports have shown worse outcomes in pts with early vs late responses (Yan Blood Adv 2019). The double-blind, randomized TOURMALINE-MM2 (NCT01850524) trial (Facon Blood 2021) showed a clinical meaningful progression-free survival (PFS) benefit with IRd vs pbo-Rd (median 35.3 vs 21.8 mos; hazard ratio, 0.830; 95% confidence interval, 0.676-1.018; P=0.073; median follow-up, 53.3 and 55.8 mos, respectively) in NDMM pts. Safety data were consistent with the established toxicity profile of IRd. We evaluated PFS and duration of response (DOR) by depth of best confirmed response and time to best response in TOURMALINE-MM2. Methods: Pts were randomized to receive oral ixazomib 4 mg (n=351) or placebo (n=354) on days 1, 8, and 15, plus oral lenalidomide 25 mg (10 mg if creatinine clearance ≤60 mL/min) on days 1-21 and oral dexamethasone 40 mg (20 mg in pts aged >75 years) on days 1, 8, 15, and 22 in 28-day cycles. After 18 cycles, treatment was continued without dexamethasone and reduced doses of ixazomib (3 mg) and lenalidomide (10 mg) until progressive disease (PD)/toxicity. Response assessments were performed every cycle until PD, or every 4 weeks in pts who discontinued treatment prior to PD. PFS and DOR were analyzed post-hoc in subgroups defined by depth of response and in subgroups defined by time to best confirmed response; 'early' and 'late' responses were defined by time to best confirmed response of 0-4 and >4 mos, respectively (additional analyses were performed by time to best confirmed response of 0-6 and >6 mos). Pts in either subgroup could have recorded an initial response prior to their best response. PFS and DOR were evaluated from randomization to progression and time of initial response to progression, respectively. To address potential guarantee-time bias in the PFS analysis, and to eliminate potential bias due to transient responses in DOR analysis, sensitivity analyses were conducted in pts with PFS / DOR of ≥6 mos. Results: Among the 705 pts in the intention-to-treat (ITT) population, 20% (26% IRd vs 14% placebo-Rd) had a best confirmed response of complete response (CR) or stringent CR, 35% (37 vs 34%) had VGPR, 26% (19 vs 32%) had PR, 10% (9 vs 10%) had stable disease (SD), 3% (1 vs 4%) had PD. 7% (8 vs 6%) of pts were not evaluable. In a pooled analysis of both arms, achieving a deeper response was associated with longer PFS (Figure, A) and DOR (median not reached [NR], 42.8, and 15.0 mos for pts with ≥CR, VGPR, and PR, respectively). In 570 pts with ≥PR (288 IRd; 282 pbo-Rd), 152 (53%) and 136 (47%) in the IRd arm and 143 (51%) and 139 (49%) pts in the pbo-Rd arm were defined as early (0-4 mos) and late (>4 mos) responders, respectively. For early vs late responders, 46% vs 40% were aged ≥75 years, 21% vs 12% had International Staging System stage III MM, and 44% vs 33% had expanded high-risk cytogenetic abnormalities. Median PFS was prolonged among late vs early responders with IRd (65.7 vs 21.2 mos) and pbo-Rd (62.6 vs 18.2 mos), as was median DOR (IRd, NR vs 22.6 mos; pbo-Rd, 64.1 vs 17.2 mos). The PFS sensitivity analysis among pts with PFS of ≥6 mos confirmed the association of late response with improved outcomes; among late vs early responders achieving ≥PR, median PFS was 65.7 vs 23.9 mos with IRd and 62.6 vs 18.4 mos with pbo-Rd (Figure, B), and among late vs early responders achieving ≥VGPR, median PFS was 65.7 vs 35.3 mos with IRd and 64.4 vs 21.7 with pbo-Rd. Conclusions: Achieving a deeper response was associated with prolonged PFS and DOR in NDMM patients in TOURMALINE-MM2. PFS benefit on the ITT analysis was driven by the higher rates of deep responses (≥VGPR) with IRd vs pbo-Rd. PFS and DOR were also longer in pts achieving a late vs early best confirmed response of ≥PR or ≥VGPR. Consistent with results from a similar analysis in relapsed/refractory MM in the TOURMALINE-MM1 trial (Garderet Leukemia 2018), our findings support the continuation of therapy with the aim of achieving a deeper response over time. Additional sensitivity analyses will be presented. Figure 1 Figure 1. Disclosures Richardson: Sanofi: Consultancy; AstraZeneca: Consultancy; Celgene/BMS: Consultancy, Research Funding; GlaxoSmithKline: Consultancy; Regeneron: Consultancy; Oncopeptides: Consultancy, Research Funding; Protocol Intelligence: Consultancy; Secura Bio: Consultancy; Janssen: Consultancy; Takeda: Consultancy, Research Funding; AbbVie: Consultancy; Karyopharm: Consultancy, Research Funding; Jazz Pharmaceuticals: Consultancy, Research Funding. Venner: Takeda: Honoraria; BMS: Honoraria; Janssen: Honoraria; Pfizer: Honoraria; Sanofi: Honoraria; GSK: Honoraria. Bahlis: GlaxoSmithKline: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; BMS/Celgene: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Genentech: Consultancy; Sanofi: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria. White: Amgen: Consultancy, Honoraria; Antengene: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Forus: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; GSK: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria. Karlin: Celgene-BMS: Honoraria, Other: member of advisory board; Sanofi: Honoraria; oncopeptide: Honoraria; Janssen: Honoraria, Other: member of advisory board, travel support; Abbvie: Honoraria; GSK: Honoraria, Other: member of advisory board; Amgen: Honoraria, Other: travel support and advisory board ; Takeda: Honoraria, Other: member of advisory board. Rigaudeau: Takeda: Membership on an entity's Board of Directors or advisory committees. Suzuki: Bristol-Myers Squibb: Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria; ONO: Honoraria; Novartis: Honoraria; Sanofi: Honoraria; Abie: Honoraria; Janssen: Consultancy, Honoraria. Shibayama: Mundi Pharma: Honoraria; Otsuka: Honoraria; Pfizer: Honoraria; Bristol-Myers Squibb: Honoraria; Sanofi: Honoraria; Nippon Shinyaku: Honoraria; Fujimoto: Honoraria; Daiichi Sankyo: Honoraria; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees; Essentia Pharma Japan: Research Funding; Chugai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Eisai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Avvie: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Celgene: Research Funding. Zhang: Takeda: Current Employment. Kumar: Takeda: Current Employment, Current holder of stock options in a privately-held company. Twumasi-Ankrah: Takeda: Current Employment. Labotka: Takeda: Current Employment. Rifkin: Takeda: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Fresenius-Kabi: Membership on an entity's Board of Directors or advisory committees; Coherus: Membership on an entity's Board of Directors or advisory committees; McKesson: Current Employment, Current equity holder in publicly-traded company; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb (Celgene): Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Lonial: AMGEN: Consultancy, Honoraria; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; BMS/Celgene: Consultancy, Honoraria, Research Funding; GlaxoSmithKline: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Merck: Honoraria. Kumar: Antengene: Consultancy, Honoraria; Carsgen: Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bluebird Bio: Consultancy; Beigene: Consultancy; Tenebio: Research Funding; Roche-Genentech: Consultancy, Research Funding; Novartis: Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding. Moreau: Amgen: Honoraria; Oncopeptides: Honoraria; Janssen: Honoraria; Celgene BMS: Honoraria; Sanofi: Honoraria; Abbvie: Honoraria. OffLabel Disclosure: Use of the oral proteasome inhibitor ixazomib in newly diagnosed multiple myeloma patients who are ineligible for transplant.

Background: The Spanish Myeloma Group (GEM) demonstrated that post-transplant maintenance with thalidomide plus bortezomib was superior to thalidomide alone, although this combination was associated with a high rate of peripheral neuropathy. Lenalidomide is currently the standard postransplant maintenance treatment, and its association with ixazomib, an oral proteasome inhibitor that does not cause peripheral neuropathy, could be of interest. Aim: To assess the potential benefit of postransplant maintenance therapy with Ixazomib /lenalidomide/dexamethasone (IRd) over lenalidomide/dexamethasone (Rd). Patients: Patients who where at least with stable disease after the GEM2012menos65 trial that included VRD-GEM induction, autologous hematopoietic stem cell transplantation conditioned with either melphalan-200 or intravenous busulfan together with melphalan-140 and consolidation with VRD-GEM were randomized to receive maintenance treatment with IRd versus Rd. Each cycle lasted 28 days. Rd arm consisted of lenalidomide 15 mg/d on days 1-21 and 20mg of dexamethasone administered orally on days 1-4 and 9-12. In IRd arm ixazomib 4 mg/day on days 1, 8 and 15 of the cycle was added. At two years, patients with negative MRD discontinued maintenance treatment. Patients with positive MRD continued with Rd for 3 additional years. In this case, 20 mg of dexamethasone was only administered on days 1-4 of the cycle. From November 24, 2014 to May 18, 2017, 161 patients were allocated to Rd arm and 171 to IRd arm. Patient characteristics at screening and prognostic factors such as ISS, cytogenetics and plasmacytomas, as well as response status, were similarly distributed in the two arms. Overall, 22% of the patients had high-risk cytogenetics [t(4;14), t(14;16) and/or 17p deletion]. MRD was analyzed by using next-generation flow at a sensitivity level of 3x10 -6. Results: After a median follow-up of 56 months, there was no difference in PFS between the two maintenance arms (median not reached, PFS at 5 years: 62% vs. 63% with IRd and Rd, respectively, p=0.785) (figure 1). In the overall series, there were no significant differences in PFS or OS among patients with standard (SR) or high-risk (HR) cytogenetics. Median PFS had not been reached in patients with SR in both arms (PFS at 5 years: 66% with IRD vs. 62% with Rd, p=0.633). In patients with HR the median PFS was 62 months with IRd vs. not reached with Rd (p=0.636). No significant differences across subgroups (ISS, conditioning, cytogenetics or MRD) were observed between IRd and Rd. Negative MRD at screening overcomes the bad prognosis of cytogenetics (PFS at 5 years 78% for SR and 80% for HR; OS at 5 years was 90% for both, SR and HR). Patients with SR who had negative MRD at screening had a significantly longer PFS (PFS at 5 years 78% vs. 50%, p Conclusions: Maintenance therapy with lenalidomide and dexamethasone in patients homogeneously treated with VRD-GEM induction, ASCT and VRD-GEM consolidation resulted in a long PFS of 63% at 5 years from the start of maintenance. The addition of ixazomib did not result in a PFS benefit. This could be partially explained by the higher toxicity leading to dose reductions or discontinuation of ixazomib in the IRd arm. Figure 1 Figure 1. Disclosures Rosinol: Janssen, Celgene, Amgen and Takeda: Honoraria. Oriol: Oncopeptides: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS/Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Jarque: AbbVie: Consultancy, Speakers Bureau; Alexion: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Apellis: Consultancy; AstraZeneca: Consultancy, Speakers Bureau; Beigene: Consultancy; CellTrion: Consultancy; Eusa: Consultancy; Gilead: Consultancy, Speakers Bureau; Grifols: Consultancy; Incyte: Consultancy; Janssen: Consultancy, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Pfizer: Consultancy, Speakers Bureau; Roche: Consultancy, Speakers Bureau; Servier: Speakers Bureau; Shionogi: Consultancy; Sobi: Consultancy; Takeda: Consultancy, Speakers Bureau. Moraleda: Pfizer: Other: Educational Grants, Research Funding; Sanofi: Other: Educational Grants, Research Funding; MSD: Other: Educational Grants, Research Funding; ROCHE: Consultancy, Honoraria, Other: Educational Grants, Research Funding; Takeda: Consultancy, Honoraria, Other: Educational Grants, Research Funding; Sandoz: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Other: Educational Grants, Research Funding; Gilead: Consultancy, Honoraria, Other: Educational Grants, Research Funding; Jazz Pharmaceuticals: Consultancy, Honoraria, Other: Educational Grants, Research Funding; NovoNordisk: Other: Educational Grants, Research Funding; Janssen: Other: Educational Grants, Research Funding; Celgene: Other: Educational Grants, Research Funding; Amgen: Other: Educational Grants, Research Funding. Sureda: Mundipharma: Consultancy; Bluebird: Membership on an entity's Board of Directors or advisory committees; Roche: Other: Support for attending meetings and/or travel; GSK: Consultancy, Honoraria, Speakers Bureau; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Kite, a Gilead Company: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; MSD: Consultancy, Honoraria, Speakers Bureau; BMS/Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Support for attending meetings and/or travel, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Support for attending meetings and/or travel, Research Funding, Speakers Bureau. Martínez-López: Roche, Novartis, Incyte, Astellas, BMS: Research Funding; Janssen, BMS, Novartis, Incyte, Roche, GSK, Pfizer: Consultancy. De Arriba: BMS-Celgene: Consultancy, Honoraria, Speakers Bureau; Glaxo Smith Kline: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Speakers Bureau. Mateos: Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene - Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bluebird bio: Honoraria; GSK: Honoraria; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sea-Gen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Regeneron: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria; Oncopeptides: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees. San-Miguel: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, GlaxoSmithKline, Janssen, Karyopharm, Merck Sharpe & Dohme, Novartis, Regeneron, Roche, Sanofi, SecuraBio, and Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees. Lahuerta: Celgene: Other: Travel accomodations and expenses; Celgene, Takeda, Amgen, Janssen and Sanofi: Consultancy. Bladé Creixenti: Janssen, Celgene, Takeda, Amgen and Oncopeptides: Honoraria.

Background: Standard chemoimmunotherapy for first-line treatment of follicular lymphoma (FL) achieves high rates of disease control but is not curative and carries significant toxicities including prolonged immunosuppression that may attenuate response to vaccinations (Marcus et al., NEJM 2017). While proteasome inhibitors have shown modest activity in R/R FL (Goy et al., JCO 2005), limited data address their use frontline. The comparatively favorable toxicity profile and convenient oral dosing of ixazomib support its investigation in this space. Methods: We evaluated ixazomib and its combination with short-course rituximab (R) for FL as part of an open-label, phase II investigator-initiated trial at the University of Washington / Fred Hutch Cancer Research Center / Seattle Cancer Care Alliance (NCT 02339922). Eligibility included an indication for treatment per NCCN guidelines and no prior standard systemic FL therapy. Ixazomib was administered at 4 mg orally once a week until disease progression or unmanageable toxicity. One course of R at 4 weekly doses of 375 mg/m 2 was added during the 7 th 28-day cycle, after an initial 6-cycle "window" on ixazomib alone. Available pretreatment formalin-fixed, paraffin-embedded tissue biopsies were subjected to RNA extraction by standard methods and gene expression profiling (GEP) using the NanoString™ PanCancer IO 360 panel to query pathways in proteasomal degradation and lymphomagenesis. Standard GEP quality control and data processing were performed with the ROSALIND® platform. Patients vaccinated per standard of care for COVID-19 while actively receiving ixazomib and ≥ 6 mo after completing R were evaluated for serologic response ≥ 2 weeks after the final dose of vaccine using the Roche Elecsys® Anti-SARS-CoV-2 S assay against the spike protein receptor binding domain. Results: Twenty pts began therapy between Feb 2017 and January 2020. All had grade I/II FL and FLIPI score was 2 in 20% and ≥ 3 in 20%; FLIPI score in all other patients was 0 or 1. Eleven (55%) pts met GELF criteria for high tumor burden disease including 6 (30%) pts with a tumor mass ≥ 7 cm. Median follow-up was 32.1 months (range 5.7 - 51.6). The ORR by Lugano criteria was 35% (CR 5%) during the ixazomib window and 65% (CR 45%) overall. At data cut (June 15, 2021) all patients were alive and 8 (40%) remained progression-free on treatment (Figure 1). By KM estimate, median PFS was 25.8 mo and median DOR was not reached at a median follow-up of 29.6 mo. As expected, high-grade treatment-related AEs were infrequent for ixazomib and R, including grade ≥ 3 events in 3 unique pts (15%; diarrhea, transaminitis, and cytopenias). No grade ≥ 4 or serious AEs were observed. Toxicities led to study-directed drug interruptions in 4 (20%) pts and dose reduction to ixazomib 3 mg weekly in 2 pts (10%). Higher ORR to ixazomib monotherapy was associated with FLIPI > 1 (p = 0.04) and, by exploratory GEP, downregulation of components of proteasomal degradation and upregulation of NF-KB and chemokine signaling (Figure 2). High tumor burden by GELF (p = 0.89) and tumor mass ≥ 7 cm (p = 0.26) were not associated with ORR to ixazomib. All 6 of 6 patients evaluated to date for response to COVID-19 vaccination, administered at a median of 32.5 mo (range 7.0 - 41.0) after last dose of R, achieved positive anti-spike protein antibodies (median anti-S 163.8 AU/mL, range 13.3 - 1139); none was diagnosed with COVID-19. Conclusions: The simple outpatient regimen of weekly oral ixazomib and the addition of 4 doses of R shows significant long-term activity with low toxicity in untreated FL. Extended DOR is achievable especially in patients who respond to ixazomib monotherapy. Ixazomib efficacy was associated with higher FLIPI scores and gene expression signatures implicated in proteasomal degradation and B-cell signaling pathways. Ixazomib deserves further investigation as a biomarker-driven therapeutic in untreated FL, particularly as an option that prioritizes outpatient management and serologic responsiveness to immunization. Figure 1 Figure 1. Disclosures Graf: MorphoSys: Consultancy, Research Funding; TG Therapeutics: Research Funding; AstraZeneca: Research Funding; BeiGene: Research Funding; GSK: Research Funding. Lynch: Incyte: Research Funding; SeaGen: Research Funding; TG Therapeutics: Research Funding; Cyteir: Research Funding; Genentech: Research Funding; Morphosys: Consultancy; Bayer: Research Funding; Juno Therapetics: Research Funding. Ujjani: Gilead: Honoraria; ACDT: Honoraria; Kite, a Gilead Company: Honoraria; Adaptive Biotechnologies: Research Funding; Janssen: Consultancy; TG Therapeutics: Honoraria; Loxo: Research Funding; Atara Bio: Consultancy; Epizyme: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; AstraZeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Cowan: Bristol Myers Squibb: Research Funding; Secura Bio: Consultancy; Sanofi Aventis: Consultancy, Research Funding; Harpoon: Research Funding; Abbvie: Consultancy, Research Funding; Nektar: Research Funding; GSK: Consultancy; Cellectar: Consultancy; Janssen: Consultancy, Research Funding. Smith: Millenium/Takeda: Consultancy; ADC Therapeutics: Consultancy; KITE pharm: Consultancy; Incyte Corporation: Research Funding; Beigene: Consultancy, Research Funding; Merck Sharp & Dohme Corp: Research Funding; Portola Pharmaceuticals: Research Funding; Ignyta (spouse): Research Funding; Genentech: Research Funding; AstraZeneca: Consultancy, Research Funding; Karyopharm: Consultancy; De Novo Biopharma: Research Funding; Bristol Myers Squibb (spouse): Research Funding; Incyte: Consultancy; Acerta Pharma BV: Research Funding; Bayer: Research Funding; Ayala (spouse): Research Funding. Shadman: Mustang Bio, Celgene, Bristol Myers Squibb, Pharmacyclics, Gilead, Genentech, Abbvie, TG Therapeutics, Beigene, AstraZeneca, Sunesis, Atara Biotherapeutics, GenMab: Research Funding; Abbvie, Genentech, AstraZeneca, Sound Biologics, Pharmacyclics, Beigene, Bristol Myers Squibb, Morphosys, TG Therapeutics, Innate Pharma, Kite Pharma, Adaptive Biotechnologies, Epizyme, Eli Lilly, Adaptimmune , Mustang Bio and Atara Biotherapeutics: Consultancy. Libby: Janssen: Consultancy, Research Funding; BMS: Research Funding; Genentech: Research Funding; GSK: Research Funding. Godwin: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company; Pfizer: Research Funding. Gopal: Genetech: Consultancy, Honoraria, Research Funding; Karyopharm: Consultancy, Honoraria; Incyte: Honoraria; Acrotech: Consultancy, Honoraria; ADC Therapeutics: Consultancy, Honoraria; Kite: Consultancy, Honoraria; MorphoSys: Honoraria; Epizyme: Consultancy, Honoraria; Gilead: Consultancy, Honoraria, Research Funding; Teva: Research Funding; IGM Biosciences: Research Funding; Bristol Meyers Squibb: Research Funding; Astra-Zeneca: Research Funding; Cellectar: Consultancy, Honoraria; Agios: Research Funding; Takeda: Research Funding; Merck: Consultancy, Honoraria, Research Funding; Servier: Consultancy, Honoraria; I-Mab bio: Consultancy, Honoraria, Research Funding; Nurix Inc: Consultancy, Honoraria; Beigene: Consultancy, Honoraria; SeaGen: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding. OffLabel Disclosure: Ixazomib is not approved for use in follicular lymphoma.

Background ： During the past decade, bortezomib, lenalidomide and dexamethasone (VRd) followed by lenalidomide maintenance has become one of the most effective first-line regimens in multiple myeloma (MM) and been recommended by many guidelines. However, when disease relapses after VRd induction and lenalidomide maintenance, further generation of proteasome inhibitors or immunomodulator drugs, or agents with different mechanism should be considered. Pomalidomide, a new-generation oral immunomodulator drug, can overcome lenalidomide resistance and has better efficacy and safety in MM patients. Pomalidomide has a synergistic effect with proteasome inhibitor and dexamethasone, which has been proved more effective than pomalidomide and dexamethasone dual-drug regimen in relapsed or refractory MM (RRMM) patients (Richardson, et al. Lancet Oncol 2019). The overall response rate (ORR) of lenalidomide retreatment is only 54% (Sumit, et al. Blood 2011). A convenient and safe pan-oral regimen, ixazomib, pomalidomide and dexamethasone (IxaPd) is expected to improve the efficacy and survival in RRMM patients. The purpose of this study is to evaluate the efficacy and safety of IxaPd regimen in RRMM patients who have received lenalidomide in China. Study Design and Methods: This multi-center open-label, single-arm study (NCT04989140) will enroll patients with measurable M protein who have received 1 to 3 prior lines of therapy (including lenalidomide) with documented disease progression during or after their most recent treatment. Patients aged ≥18 years with Eastern Cooperative Oncology Group Performance Status 0-2, expected overall survival (OS) ≥3 months, and who provide informed consent will be eligible. Patients with prior exposure to pomalidomide, ixazomib and those intolerant/refractory to bortezomib will be excluded. Eligible 60 patients will be enrolled in this IxaPD regimen. Clinical and laboratory parameters will be recorded at baseline. Cytogenetic abnormalities are tested via fluorescence in situ hybridization (FISH) in CD138 sorted myeloma cells. Ixazomib 4 mg on days 1, 8 and 15 every 28 days, pomalidomide 4mg qd day 1-21 every 28-day, dexamethasone 40 mg (20 mg for patients >75 years of age) every week will be administrated. Treatment will continue until disease progression or unacceptable toxicity. Drug doses will be adjusted or withdrawn according to the degree of toxicities. The primary endpoint is progression free survival (PFS), the secondary endpoints include OS, time to next treatment (TTNT), ORR, safety. Patients are stratified into subpopulation on the basis of cytogenetic abnormalities, prior treatment lines and exposure drugs, ect. PFS, OS and TTNT were analyzed by Kaplan-Meier survival plot. Response will be evaluated according to International Myeloma Working Group (IMWG) 2016 criteria, and done at baseline and each cycle from 1-5, then every other cycle till cycle 13, and every three cycles till cycle 28 if the subjects do not relapse. Patients who reach complete response (CR) need to perform a minimal residual disease (MRD) test via next-generation flow (NGF) . Conclusion: This is the first prospective clinical study to examine the efficacy and safety of pan-oral IxaPd regimen for RRMM in Chinese patients. Disclosures Research sponsor: CHIATAI TIANQING PHARMACEUTICAL GROUP. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Introduction: Lenalidomide-based regimens are currently among the standard-of-care treatment options for newly diagnosed patients with multiple myeloma NDMM). Second-line treatment of patients who are refractory to lenalidomide or have relapsed after prior use of lenalidomide is challenging. Daratumumab, an IgG1κ human monoclonal antibody that targets CD38, has shown durable responses and a favorable safety profile in heavily pretreated patients with relapsed/refractory MM (RRMM) as monotherapy, or in combination with other anti-myeloma treatments. Ixazomib, the first oral proteasome inhibitor, has shown deep responses and a positive safety profile in NDMM patients when it is combined with lenalidomide and dexamethasone. The aim of the DARIA study is to evaluate the effectiveness of daratumumab in combination with ixazomib and dexamethasone (DId) as second-line therapy in patients who have received prior treatment with lenalidomide-based regimens. Methods: DARIA is an ongoing prospective, open-label, multicenter, phase 2 study, which aims to enroll 43 patients who have received one prior line of therapy with a lenalidomide-based regimen. Patients must have a Karnofsky performance status (PS) ≥70. Exclusion criteria include previous daratumumab or anti-CD38, or ixazomib treatment exposure. The treatment phase consists of an induction therapy for 9 cycles, followed by a maintenance period. The induction phase included 28-day treatment cycles with 16 mg/kg intravenous daratumumab (weekly for cycles 1-2, every 2 weeks for cycles 3-6, and every 4 weeks thereafter), 4 mg oral ixazomib (Days 1, 8, and 15 of each cycle), and 40 mg oral dexamethasone for the first 9 cycles (weekly, each cycle). During the maintenance phase of the study daratumumab is administered every 4 weeks and ixazomib on the same schedule, until disease progression or unacceptable toxicity whereas dexamethasone is discontinued. The primary endpoint is the overall response rate (ORR). Secondary endpoints include evaluation of the toxicity profile of the study treatment, progression-free survival (PFS), overall survival, and levels of serum bone markers and angiogenic cytokines. All responses are based on investigators' assessment per International Myeloma Working Group criteria. This analysis presents results for patients who received the first dose of study treatment ≥5 months prior to the cut-off date (01/05/2020). Results: Fifteen patients, enrolled in 4 Sites, are included in the current analysis. Overall, 60% of the patients were refractory to lenalidomide. Median age was 70 years and the majority of patients were male (60%). The median time from diagnosis to first dose of study treatment was 1.3 years. Two patients (13%) had a prior autologous stem cell transplantation. Patients had a Karnofsky PS of 70 (27%), 80 (7%), 90 (53%), and 100 (13%) at baseline. At screening 47%, 26%, and 27% of the patients had an international staging system (ISS) of 1, 2, and 3, respectively, and a revised ISS of 1 (21%), 2 (71%), and 3 (7%). The median number of cycles reached until the cut-off date was 7. The median time from first dose of study treatment until first partial (PR) or very good partial response (VGPR) was 0.9 month. ORR was 60%, with 47% of the patients achieving VGPR and 13% PR. The 12-month PFS rate was 54%, and 8 patients (53%) were still on treatment by the cut-off date. From the patients who discontinued 71% was due to disease progression and 29% due to physician's decision. Overall, 10 patients (67%) had at least one adverse event (AE) grade 3 or 4, the most common being thrombocytopenia (6 patients, 40%). Four patients (27%) had a single SAE each: lower respiratory tract infection (fatal); peritonitis, gastroenteritis; nephrolithiasis. Conclusions: Rapid (median time to PR or better was 1 month) and deep responses (47% of the patients exhibited VGPR) were observed following treatment with daratumumab, ixazomib and dexamethasone as second-line therapy in patients who were previously treated with a lenalidomide-based regimen, more than half of whom were refractory to lenalidomide. The safety profile of DId combination is very good with one third of the patients not experiencing any grade 3 or 4 AEs, when at the same time the PFS rate at 12 months reached 54%. Disclosures Terpos: Janssen: Honoraria, Research Funding; Takeda: Honoraria, Other: travel expenses , Research Funding; Celgene: Honoraria; Amgen: Honoraria, Research Funding; Genesis pharma SA: Honoraria, Other: travel expenses , Research Funding; Sanofi: Honoraria; BMS: Honoraria. Gavriatopoulou:Amgen: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; Genesis Pharma: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria. Katodritou:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Research Funding; Abbvie: Research Funding; Janssen-Cilag: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Theagenion Cancer Hospital: Current Employment; Takeda: Honoraria, Other: Expenses, Research Funding; Genesis Pharma: Honoraria, Other: Expenses, Research Funding. Hatjiharissi:Abbvie: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Genesis pharma SA: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria. Verrou:Amgen: Honoraria; Abbvie: Honoraria; Janssen Cilag: Honoraria, Research Funding; Karyopharm: Research Funding; Takeda: Honoraria; Roche: Honoraria; Genesis: Honoraria. Leonidakis:Health Data Specialists S.A.: Current Employment. Delimpasi:Janssen: Honoraria; Takeda: Honoraria; Amgen: Honoraria; GENESIS: Honoraria. Symeonidis:Sanofi/Genzyme: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GenesisPharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Research Funding; WinMedica: Research Funding; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck Sharp & Dohme: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Astellas: Research Funding. Kastritis:Amgen: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria; Genesis Pharma: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria. Dimopoulos:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees, Research Funding, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees, Research Funding, Speakers Bureau; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Personal fees.

BACKGROUND: PIs combined with an Rd backbone are the most commonly used triplet combination regimens in patients (pts) with RRMM in the US. The hallmark trials supporting the efficacy of these regimens were predominantly in pts without prior exposure to lenalidomide (R).1,2 Real-world analyses have shown that R-based regimens are increasingly used in the front-line setting.3-5 Thus, real-world treatment patterns in pts with prior R exposure and the real-world comparative effectiveness of PI-Rd triplets in this population with RRMM needs further elucidation. METHODS: A retrospective cohort of RRMM pts initiating IRd, KRd, or VRd in line of therapy (LOT) ≥2 were followed between 7/2007-9/2018 in Optum's deidentified national electronic health records database. RRMM pts were defined as those initiating LOT ≥2 between 1/2014 and 9/2018 and were categorized as having or not having prior exposure to R (R-exposed; no-prior-R) in any prior LOT. Index regimen was the first use of I-/K-/or V-Rd. LOTs were defined via an algorithm developed with MM specialists to proxy the definition of a LOT in RCTs & in accordance with NCCN MM Guidelines.6 Baseline data included: CRAB (hyperCalcemia, Renal insufficiency, Anemia, and Bone lesions); high risk cytogenetics (defined as del[17p], 1q21 gain, t[4;14], or t[14;16]); Charlson Comorbidity Index (CCI) score; and modified frailty score using age and CCI score. Median duration of therapy (DOT) and time-to-next-treatment (TTNT) (a proxy for PFS; defined as time from index regimen start to subsequent LOT or death) were estimated using Kaplan-Meier methods and compared using covariate-adjusted Cox proportional hazard models (FIGURE). Observations were censored at time of loss to follow-up (f/u)/end of study period (9/30/2018). RESULTS: Of 650 pts included, 397 were R-exposed (IRd, n=112; KRd, n=115; VRd, n=170); 253 had no-prior-R (IRd, n=29; KRd, n=62; VRd, n=162). R-exposed pts, overall, were treated in later LOTs (LOT2: 55% v 78%) and had a longer median time from diagnosis to index LOT (26.7 v 13.4 months) than no-prior-R pts; this differed between treatment cohorts (TABLE). In R-exposed pts, more pts with symptomatic relapse (≥1 CRAB symptom, 87%) or high-risk cytogenetics (30%) received KRd than IRd (75% & 23%) or VRd (74% & 16%) (TABLE). More pts treated with IRd were ≥75 years old: 42% (IRd) v 36% (VRd) / 21% (KRd). In R-exposed pts, 35.3% of those receiving VRd in LOT ≥2 had prior V-IMID-based and 53.5% had IMID-based therapy (ie, IMID with no PI nor monoclonal antibody) in LOT1; >98% of LOT1 IMID use was R, across groups. In R-exposed pts, 56.5% of those receiving KRd had prior V-IMID-based and 16.5% had IMID-based therapy in LOT1; in IRd pts in LOT ≥2, 29.5% and 43.8% had prior V-IMID-based and IMID-based therapy in LOT1. In unadjusted analysis, at a median f/u of 11, 11.9, and 14.8 months for I-, K-, and V-Rd, median TTNT for R-exposed pts: 12.3 months (IRd), 7.8 months (KRd), and 13.9 months (VRd) (P=0.50); HRs for TTNTLOT stratified: 0.84 (IRd v KRd), 0.96 (IRd v VRd), 1.15 (KRd v VRd), and median regimen DOTs: 8.4 months (IRd), 7.5 months (KRd), and 9.5 months (VRd) (P=0.75). In no-prior-R pts, HRs for TTNTLOT stratified were significant for IRd v KRd (HR=0.33) and KRd v VRd (HR=1.62) (P CONCLUSIONS: In this real-world study, the majority of pts received a PI-Rd combination after prior VRd or Rd in front-line. After controlling for baseline characteristics, including prior PI-exposure, PI-Rd triplets were comparable in TTNT in R-exposed pts treated in LOTs ≥2. TTNT was significantly longer for I- v K-Rd in pts with no-prior-R, although this is limited by small sample size. Published studies indicate that individualized treatment recommendations may improve real-world outcomes, such as IRd v KRd in frail pts which was associated with significantly longer TTNT.6 Prior-R exposure, in our analysis, does not appear to influence the relative PI-triplet regimen effectiveness in LOTs ≥2. With increasing use of R in earlier LOTs, understanding real-world treatment patterns and subsequent PI-Rd effectiveness in consequent LOTs is key for optimizing RRMM pt management. Disclosures Cherepanov: Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Romanus:Takeda: Current Employment. Raju:Xcenda: Current Employment, Other: Xcenda received research funding from Takeda. Blazer:Xcenda: Current Employment, Other: Xcenda received research funding from Takeda. Farrelly:Xcenda: Current Employment, Other: Xcenda received research funding from Takeda. Stull:Takeda: Current Employment. Ailawadhi:Phosplatin: Research Funding; Celgene: Honoraria; Amgen: Research Funding; Takeda: Honoraria; Janssen: Research Funding; Pharmacyclics: Research Funding; Cellectar: Research Funding; BMS: Research Funding; Medimmune: Research Funding.

Introduction: Three drug regimen using bortezomib (V), lenalidomide (R), and dexamethasone (d) is a standard first-line treatment modality for multiple myeloma (MM). If compared to bortezomib that can cause neurotoxicity, ixazomib is an oral proteasome inhibitor (PI) with markedly lower chances of neurotoxicity. Ixazomib (I) use showed favorable results in both newly diagnosed MM (NDMM) and relapsed refractory MM (RRMM). This systemic review compares the efficacy and safety outcomes of IRd with VRd in MM patients. Methods: We performed a comprehensive literature search on PubMed, Cochrane Library, and ClinicalTrials.gov on June 9, 2020. We used the MeSH terms for 'multiple myeloma', 'ixazomib', 'bortezomib', 'dexamethasone', 'lenalidomide', and their associated keywords. The search yielded 1117 articles. Screening and data extraction were done following PRISMA guidelines. After excluding case reports, case series, observational studies, review articles, meta-analysis, and retrospective studies, 18 clinical trials (n=2295) were shortlisted of which six assessed IRd and twelve assessed VRd. Results: No direct comparison trial between IRd and VRd was found. Total 1007 patients were evaluable who received IRd (Table 1). Among them 892 had RRMM and 115 had NDMM. Moreover, total 1288 evaluable patients received VRd where 977 had NDMM and 311 had RRMM (Table 3). IRd arm results Among 892 RRMM patients received IRd, Gupta et al. (2015, n=43) reported an overall response rate (ORR) of 65% with 23% achieving a very good partial response (VGPR) and 9% achieving complete response (CR). In TOURMALINE-MM1 Study by Moreau et al. (2016, n=722), authors reported the median progression-free survival (mPFS) as 20.6 months with IRd. The ORR was 78% (95% CI 74-83). Hou et al. (2017, n=115) reported mPFS of 6.7 with IRd. After a median follow-up of 20.2 months, the median overall survival (mOS) was reported to be 25.8 months. The ORR was 56% (95% CI 42-69). 115 NDMM patients received IRd in two clinical tials. Richardson et al. (2018, n=50) in a phase II trial reported an ORR of 94% (95% CI 83-99) with 29% CR and 37% VGPR. The mPFS was 24.9 months (95% CI 17.4-40.5) and 3-year OS was 90% in the intention-to-treat analysis. Kumar et al. (2019, n=65) reported ORR of 88% (CR=23%, VGPR=34%, PR=64%). The mPFS of 35.4 months (95% CI 17.8-44.12) slightly better than the previous study. The mOS was not reached in either of the trials. Any drug-related grade ≥ 3 adverse events were reported in 50% to 80% of participants receiving IRd but were manageable with prompt intervention. VRd arm results NDMM patients, in a phase III trial by Durie et al. (2016, n=471) achieved ORR of 82% (PR=38%, VGPR=28% and CR=16%) with VRd. The mPFS was 43 months and mOS was 75 months, both significantly better than control. Stadtmauer et al. (2019, n=254) results were similar as well with 3-year PFS and OS as 58% and 85% respectively. Kumar et al. (2012, n=42) had a 1-year OS of 100% and PFS of 83%. O'Donnel et al. (2018, n=50) achieved mPFS of 35 months while mOS could not be reached. Luoma et al. (2019, n=78) achieved a 3-year PFS of 52% while OS of 83%. Among the 311 patients who had RRMM, Brojil et al. (2015, n=64) in phase I/II study showed ORR of 89% but mPFS and mOS were limited to 19 and 42 months respectively. In Richardson et al. (2014, n=64) 2-year PFS=36% and OS=65%. Mori et al. (2020, n=68) reported ORR=71% largely driven by PR of 43%. 1-year PFS and OS were 14% and 37% respectively. The toxicity profile with VRd was mostly mild and manageable except for severe neurotoxicity. Conclusion: Based on the data, IRd and VRd combinations have shown comparable efficacy and safety outcomes in MM patients. IRd based all-oral regimen is showing favorable outcomes, especially in RRMM patients. Future trials to compare IRd vs VRd are recommended for NDMM and RDMM patients. Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.: Honoraria, Research Funding, Speakers Bureau.

Background Ixazomib (IXA) is an orally-administered proteasome inhibitor approved in Europe in November 2016 for relapsed and/or refractory multiple myeloma (RRMM). It became available in France in May 2017 via a compassionate use program (CUP) and from October 2018 via the classical market access (non-CUP). In addition to pivotal clinical trials, real-world evidence (RWE) is required to evaluate effectiveness and safety in clinical routine practices. A non-interventional study, has been conducting in France to evaluate IXA use in combination with lenalidomide and dexamethasone (IRD) in real life. Methods REMIX is a non-interventional, multicentric study to assess IRD effectiveness and safety, conducted in 59 sites (public and private) in patients with RRMM. IRD was initiated in second line or more during the CUP and afterwards. After inclusion, patients were assessed every 3 months (mo) during 24 mo then every 6 mo as per standard practice. This interim analysis assessed IRD effectiveness (median Progression Free Survival (mPFS), 12 and 24-mo overall survival (OS) rates and tolerance in the CUP patients initiating IXA concomitantly to RD (patients who started lenalidomide more than 6 weeks before IXA were excluded). The analysis was conducted globally and per subgroups (age, number of lines of treatment, frailty as defined by Facon T & al.in Leukemia 2020). The CUP-patient median study follow-up was 17.4 mo for this interim analysis. Results The 198 eligible CUP patients were 47% of males, with a median age of 69 years (26% ≥75y). Out of them, 45% were frail and 7% had renal failure (CrCl ≤30 ml/min). Comorbidities were reported in 64% of patients including diabetes (9%), renal disease (10%), solid tumor (9%). At diagnosis, the cytogenetic risk was standard, high or unknown in respectively 46%, 13% and 41% of patients; 11% presented a plasmacytoma. 41% had multiple or severe bone lesions and 25% peripheral neuropathy. MM was diagnosed at a median of 4 years before IRD initiation. IXA was initiated after one (L2) / two (L3) / three or more lines of treatment (L4+) in respectively 58%, 18% and 24% of patients. Of them, 38% had received lenalidomide during prior line(s), mainly in patients with L3 and L4+ (78%, 65/84) vs L2 (8%, 9/114). The median washout period between lenalidomide discontinuation and IRD start was 18 mo 95%CI [17.6 - 29.6]. The mPFS was 19.2 mo 95%CI [13.3; 21.9] for the CUP cohort. mPFS was 21.5 mo 95%CI [13.3; 21.9] for L2 (104 patients), 17,8 mo 95%CI [12.2; 26.7] for L3 (29 patients) and 5.6 mo 95%CI [4.1; 8.8] for L4+ (38 patients) (c.f. Figure1). mPFS was similar in 12mo and 24mo-OS rates were 84% 95%CI [78%; 89%] and 73% 95%CI [65%; 80%] for the global group. Among the 166 patients with available response according to investigators, overall response rate (ORR) was 68% (66% in The 187 followed-up CUP patients received a median of 14 IRD cycles. IXA discontinuation was reported in 50% of patients (n=92), related to AE in 13% of cases (n= 24). Serious adverse events were reported in 34% (n=69), including 14 (7%) patients with SAE considered related to IXA. Most frequent (>10%) AE were thrombocytopenia (30%), diarrhoea (28%), asthenia (20%), anaemia (18%), neutropenia (15%), nausea (14%) and peripheral neuropathy (10%). Conclusion Few RWE data have been published for IXA use in Europe. In this first interim analysis, estimated mPFS is consistent with MM1 results or data reported in MM1 study (19,2 mo vs 20.6 mo) even though CUP patients in REMIX were globally elder, frailer and more frequently treated in advanced lines (24% of L4+ in REMIX vs 11% of L4 in MM1). Reported adverse events were in line with known safety IXA profile. Figure 1 Disclosures Laribi: abbvie: Honoraria, Research Funding; amgen: Research Funding; novartis: Honoraria, Research Funding; takeda: Research Funding. Vincent:Celgene: Membership on an entity's Board of Directors or advisory committees, Other: Congress support; takeda: Membership on an entity's Board of Directors or advisory committees, Other: Congress support; janssen: Membership on an entity's Board of Directors or advisory committees, Other: Congress support. Hulin:Celgene/Bristol-Myers Squibb, Janssen, GlaxoSmithKline, and Takeda: Honoraria. Macro:sanofi: Honoraria; gsk: Honoraria; janssen: Honoraria, Other: travel accomodation, Research Funding; takeda: Honoraria, Other: travel accomodation, Research Funding. Karlin:Celgene/Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, personal fees; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, personal fees; GlaxoSmithKline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Other: Personal fees; Sanofi: Honoraria; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, personal fees. Texier:Kappa Santé: Other: employee of the CRO in charge of REMIX. Chouaid:pfizer: Honoraria, Research Funding; GSK: Honoraria, Research Funding; novartis: Honoraria, Research Funding; pfizer: Honoraria, Research Funding; takeda: Honoraria, Research Funding; bms: Honoraria, Research Funding; msd: Honoraria, Research Funding; astra zeneca: Consultancy, Honoraria, Research Funding; amgen: Consultancy, Honoraria, Research Funding; roche: Consultancy, Honoraria, Research Funding. Leleu:GSK: Honoraria; Amgen: Honoraria; BMS-celgene: Honoraria; Janssen: Honoraria; Sanofi: Honoraria; Oncopeptide: Honoraria; Carsgen: Honoraria; Incyte: Honoraria; Merck: Honoraria; Novartis: Honoraria; AbbVie: Honoraria; Karyopharm: Honoraria.

Background: Triplet combination regimens have been widely accepted as the standard of care for the management of multiple myeloma (MM) due to improved outcomes as compared to doublet regimens. The combination of daratumumab, pomalidomide, and dexamethasone (DPd) has previously demonstrated deep and durable responses including high rates of minimal residual disease (MRD) negativity in patients with relapsed/refractory (R/R) MM. Quadruplet regimens may further improve these outcomes. We report preliminary findings from an ongoing phase 2 multi-center trial of the addition of ixazomib to DPd (DIPd) in patients with R/R MM. Methods: We are conducting a prospective, multi-center, open-label, single-arm phase 2 study to determine the efficacy and safety of DIPd as salvage therapy in R/R MM. A Simon's optimal 2-stage design includes a safety run-in period at the beginning of Stage 1 where the first 6 patients are enrolled for toxicity assessment. If ≤1 patient experiences any DLT, the study continues to accrue more Stage 1 patients. Key secondary endpoints include progression-free survival (PFS), overall survival (OS) and MRD-negativity rates. Eligible patients may have received ≥1 and ≤3 prior lines of therapy, have had no prior exposure to daratumumab or ixazomib, are lenalidomide refractory, and may have not progressed on prior pomalidomide. The first six patients were treated in a safety run-in with daratumumab 16mg/kg IV weekly x 8 doses, biweekly x 8 doses, then monthly, pomalidomide 4mg orally daily on days 1-21 of a 28-day cycle, ixazomib 4mg orally daily on days 1,8,15 every 28 days, and dexamethasone 20-40mg weekly. Patients continued therapy until disease progression, intolerability or preference. Dose-limiting toxicities (DLT) were defined as grade 3-4 hematologic adverse events (AE) or any AE that required a dose modification of pomalidomide or ixazomib at the lowest dose levels on a dose de-escalation plan. An interim safety review is being performed after the enrollment and completion of the DLT observation period for the 14 planned patients in stage I. An interim efficacy analysis was also planned after all patients had completed 3 months of therapy. Minimal residual disease assessments are being performed by EuroFlow for patients in VGPR or suspected CR. Pharmacodynamic changes in patients' tumor microenvironments were established by custom panel mass cytometry to include T-cell memory and activated subpopulations, B-cell content, NK-cell subpopulations as well as MDSCs, Tregs and T-exhaustive markers, monocytes and dendritic cells. Results: At the time of this analysis, all 14 patients have enrolled and started treatment as part of stage I of the trial. Patients had a median age of 61 (range 52-65) and median number of 1 prior line of therapy (range 1-3). All patients were refractory to lenalidomide and all were pomalidomide naïve. In the safety run-in, all 6 patients experienced ≥ grade 3 neutropenia, and per DSMB recommendation, the starting doses of pomalidomide and ixazomib were both reduced to 3mg for the subsequent 8 patients in stage 1. Common AEs included neutropenia, thrombocytopenia, and upper respiratory infection. Grade 3-4 AEs were predominantly hematologic, including neutropenia and thrombocytopenia. One patient had a grade 3 infusion-related reaction (IRR) with daratumumab administration. No DLTs have occurred. After median follow up of 4.1 months (range 1-22), all 14 patients were evaluable for efficacy. At the time of data analysis, the overall response rate to date is 85%, and the best responses include: 5 (36%) stringent complete response; 1 (7%) very good partial response; 5 (36%) partial responses; and 3 (21%) patients with stable disease. Six (42%) patients are off study treatment: 3 due to disease progression, 1 to undergo salvage autologous SCT, and 2 due to toxicity related to treatment (IRR and upper respiratory infection). MRD and pharmacodynamic data will be presented at ASH. Conclusion: The quadruplet regimen DIPd in patients with R/R MM is a well-tolerated combination and has shown early safety and promising efficacy in the first 14 patients enrolled to stage 1 of the trial. A pre-planned interim efficacy analysis is ongoing prior to future enrollment in stage 2 at multiple sites within the University of California Hematologic Malignancies Consortium. Disclosures Costello: Celgene: Honoraria, Research Funding; Janssen: Research Funding; Poseida Therapeutics: Research Funding; Takeda: Consultancy, Honoraria, Research Funding. Wieduwilt:Daiichi Sankyo: Membership on an entity's Board of Directors or advisory committees; Shire: Research Funding; Macrogeneics: Research Funding; Amgen: Research Funding; Leadiant: Research Funding; Merck: Research Funding; Reata Pharmaceuticals: Current equity holder in publicly-traded company. Shah:GSK, Amgen, Indapta Therapeutics, Sanofi, BMS, CareDx, Kite, Karyopharm: Consultancy; BMS, Janssen, Bluebird Bio, Sutro Biopharma, Teneobio, Poseida, Nektar: Research Funding.

Background: Multiple myeloma (MM) is an incurable disease, and clinical trials with newer agents have shown improved patient outcomes. There is a need for effective and tolerable treatment for patients with relapsed/refractory MM (RRMM). Proteasome inhibitors (bortezomib, carfilzomib, ixazomib) remain an integral part of regimens used in RRMM or newly diagnosed (ND) MM. This meta-analysis aims to assess the efficacy and safety of ixazomib (Ixa) based regimens in RRMM. Methods: A comprehensive literature search was performed on PubMed, Cochrane, Embase, Web of Science, and clinicaltrials.gov. We used MeSH and Emtree terms, "ixazomib" AND "multiple myeloma" from the inception of literature till 06/01/2020. We screened 1529 articles and included 3 randomized clinical trials (RCT, N=907) and 8 non-randomized clinical trials (NRCT, N=321). We excluded case reports, case series, review articles, meta-analysis, observational studies, and clinical trials that didn't provide data about the efficacy and safety of Ixa in RRMM. We used the R programming language (version 4.0.2) to conduct a meta-analysis. Results: In 11 clinical trials (N=1228), the age range of patients was 30-91 years. In Phase III RCTs (N=837) comparing Ixa + Lenalidomide (Len) + dexamethasone (Dex) vs. placebo + Len + Dex, risk ratio of overall response rate (ORR), complete response (CR), and very good partial response (VGPR) were 1.14 (95% CI=1.05-1.24, I2=80%), 1.87 (95% CI=1.17-2.99, I2=0), and 1.15 (95% CI=0.95-1.40, I2=0), respectively in favor of Ixa + Len + Dex. (Fig 1-3) Grade 3 or higher treatment-related adverse events (TRAEs) thrombocytopenia, diarrhea, and rash were reported in 20%, 5.7% and 6.4% of the patients in the Ixa group vs. 10%, 2.1%, and 2.8% in the placebo group, respectively. In a Phase II RCT by Kumar et al (N=70) comparing the Ixa dosage, 4 mg Ixa + Dex yielded an ORR of 31%, CR 2.8%, and VGPR 17.1%, while 5.5 mg Ixa yielded improved ORR of 54%, CR 2.8%, and VGPR 25.7%. In a NRCT by Costello et al. (N=6), Ixa + daratumumab (Dara) + Pom + Dex yielded 100% ORR, CR 5% (95% CI=0.17-0.83), and VGPR 50% (95% CI=0.17-0.83). ≥Grade 3 TRAEs were hypertension (16%), and hematological (33%). Among 417 patients from two RCT in single arm who received Ixa + Len + Dex, pooled ORR was 70% (95% CI=0.53-0.82, I2=84%), pooled CR 11% (95% CI=0.8-0.14, I2=0), and pooled VGPR was 29% (95% CI=0.18-0.43, I2=66%). In a NRCT by Dhakal et al. (N=19), Ixa + bendamustine + Dex yielded an ORR 58% (95% CI=0.36-0.77), CR 0, and VGPR 11% (95% CI =0.03-0.34). ≥Grade 3 TRAEs were neutropenia 31%, thrombocytopenia 52%, and diarrhea 10%. In 2 NRCT (N=106), Ixa + cyclophosphamide (Cyc) + Dex yielded a pooled ORR 52% (95% CI=0.42-0.61, I2=0), CR 4% (95% CI=0.01-0.10, I2=0), and VGPR 17% (95% CI=0.11-0.25, I2=0). ≥Grade 3 TRAEs were thrombocytopenia (15%), and upper abdominal pain (4%). In a NRCT by Ludwig et al. (N=90), Ixa + thalidomide (Thal) + Dex yielded an ORR 51% (95% CI=0.41-0.61), CR 9% (95% CI=0.5-0.17), and VGPR 14% (95% CI=0.09-0.23). ≥Grade 3 TRAEs were anemia (17.8%), and infections (16.1%). In a NRCT by Krishnan et al. (N=31), Ixa + Pomalidomide (Pom) + Dex yielded an ORR 48% (95% CI=0.32-0.65) and VGPR 16% (95% CI=0.07-0.33). (Fig 4-6) ≥Grade 3 TRAEs were neutropenia (10%), and lymphopenia (35%). In 2 NRCT by Kumar et al. (N=70) of two drugs combination, Ixa + Dex yielded a pooled ORR 43% (95% CI=0.28-0.59, I2=47%), pooled CR 1% (95% CI=0-0.09, I2=0), and pooled VGPR 24% (95% CI=0.16-0.36, I2=0). ≥Grade 3 TRAEs were hematological (28%), and non-hematological (22.8%). In 2 NRCT of Ixa monotherapy (N=69), pooled ORR was 17% (95% CI=0.10-0.28, I2=0), and pooled CR 6% (95% CI=0.2-0.22, I2=0). (Fig 4-6) ≥Grade 3 TRAEs were anemia (11%), thrombocytopenia (5.4%), and neutropenia (2.7%). Conclusion: Our study provides useful insight into relative efficacy of various Ixa regimens for the treatment of RRMM. The pooled analysis of RCT showed that the combination of Ixa + Len + Dex yielded better response as compared to placebo. In the pooled analysis of outcomes in single arm NRCT, Ixa + Dara + Pom + Dex and Ixa + Len + Dex showed better efficacy outcomes as compared to Ixa + Dex in combination with Thal, Cyc, or Bendamustin. Three drugs Ixa combination regimens had better efficacy as compared to two drugs combination of Ixa + Dex and Ixa monotherapy. Ixa was well tolerated with acceptable safety profile. Additional multicenter, double-blind clinical trials are needed to confirm these results. Disclosures Anwer: Incyte, Seattle Genetics, Acetylon Pharmaceuticals, AbbVie Pharma, Astellas Pharma, Celegene, Millennium Pharmaceuticals.: Honoraria, Research Funding, Speakers Bureau.

Background Maintenance therapy improves PFS in NDMM pts. Additional active, well-tolerated treatment options that are suitable for long-term administration are required. The international, multicenter, double-blind, placebo-controlled, phase 3 TOURMALINE-MM4 trial (NCT02312258) of the oral PI ixazomib as maintenance therapy post-induction in non-transplant NDMM pts met its primary endpoint of PFS. Ixazomib demonstrated a significant and clinically meaningful benefit vs placebo, with a manageable and well-tolerated toxicity profile. Feasible, tolerable options for long-term therapy are particularly important in this setting, as pts are often elderly and/or frail. We report herein a subgroup analysis of TOURMALINE-MM4 according to age and frailty status. Methods Pts who achieved ≥partial response (PR) after 6-12 months of standard-of-care induction therapy were randomized 3:2 to ixazomib or placebo maintenance for up to 24 months. The sum of 4 components - age (80 years; score 0 vs 1 vs 2), the Katz Index of Independence in Activities of Daily Living (ADL; >4 vs ≤4, score 0 vs 1), the Lawton Instrumental ADL Scale (>5 vs ≤5, score 0 vs 1), and the Charlson Comorbidity Index (≤1 vs ≥2, score 0 vs 1) - was used to classify pts as fit (total score: 0), unfit (score: 1), or frail (score: ≥2). Analyses of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and MY20 modules were conducted to evaluate the effects of treatment on QoL within subgroups defined by frailty status and age. Results In the ixazomib (n=425) vs placebo (n=281) arms, there were similar proportions of pts aged PFS benefit with ixazomib vs placebo was seen across age groups, with hazard ratios (HRs) of 0.576 (95% confidence interval [CI] 0.299-1.108, p=0.095, median 11.0 vs 9.3 months) in pts aged Rates of grade ≥3 treatment-emergent adverse events (TEAEs), serious TEAEs, and discontinuation due to TEAEs were higher or similar with ixazomib vs placebo across age and frailty subgroups (Table 2). Rates were generally somewhat higher in older age groups and in unfit/frail pts in both arms; nevertheless, rates of discontinuation due to TEAEs across groups were Covariate-adjusted changes in QoL subscales from baseline were estimated at each cycle using repeated measures linear mixed models stratified by frailty status. In all frailty groups, the mean changes in each treatment arm were small over time ( Conclusions Ixazomib as post-induction maintenance therapy in non-transplant NDMM pts results in PFS benefits vs placebo regardless of age or frailty status. Ixazomib appeared generally well tolerated across groups, with TEAE rates in both arms generally elevated in elderly/frail vs younger/fit pts. Ixazomib is a feasible and effective maintenance option for prolonging PFS across this heterogeneous pt population. Disclosures Bringhen: Takeda: Consultancy; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees. Vorog:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Labotka:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Wang:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Cherepanov:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Cain:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Manne:Millennium Pharmaceuticals, Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Current Employment. Dimopoulos:Celgene: Honoraria; Janssen: Honoraria; Takeda: Honoraria; Bristol-Myers Squibb: Honoraria; Beigene: Honoraria; Amgen: Honoraria. OffLabel Disclosure: Use of the oral proteasome inhibitor ixazomib as maintenance therapy in patients with newly diagnosed multiple myeloma not undergoing stem cell transplantation

Introduction Autologous stem cell transplantation (ASCT) combined with novel agents is considered as the standard treatment for eligible patients < 70(-75) years of age with multiple myeloma (MM). The number of induction cycles is usually 4-6 followed by ASCT, consolidation and maintenance. The role of consolidation is still under debate especially if complete response has been achieved and maintenance will follow. To improve the quality of life and avoid the frequent visits at hospital an all-oral treatment would be a preferred choice. Despite novel drugs, the outcome of high-risk (HR) patients is poor. We designed a phase 2 Nordic Myeloma Study Group (NMSG) trial (NCT03376672) to explore the response of ixazomib, lenalidomide and dexamethasone (IRd) induction, followed by single ASCT, IRd consolidation and risk-based maintenance either with IR or R. Here we present the response rates and safety after IRd x 4 induction in all patients and in 87% of patients before consolidation. Patients and methods This study included 120 patients in 22 NMSG sites. Patients received 4 IRd cycles as induction, ixazomib 4 mg on days 1, 8, 15, lenalidomide 25 mg on days 1-21, dexamethasone 40 mg weekly in 28-day cycles. Mobilization and ASCT were performed according to standard practice. Three months post-ASCT all patients will receive 2 IRd as consolidation followed by maintenance. Thereafter patients will be stratified to HR if any of the following FISH aberrations were found at inclusion: del17p at least 60%, t(4;14), t(14;16), t(14;20) or +1q and they receive ixazomib 4 mg on days 1, 8, 15 and lenalidomide 10 mg on days 1-21. Non-HR patients receive lenalidomide 10 mg on days 1-21. Maintenance will continue until progression (PD). Lenalidomide dose will increase to 15 mg after 3 cycles. The primary endpoint of the study is minimal residual disease (MRD) by 8-color Euroflow < 0.01%. The secondary endpoints include flow-MRD negativity by 10-5, overall response, safety and progression-free survival. Serological responses were assessed before cycles and if sCR or CR is achieved flow-MRD sampling will be performed and repeated every 6 months. Samples were taken concomitantly for later comparison with BM- molecular-MRD, blood cell-free DNA, blood heavy-light chain assay and blood mass spectrometry. Results Within 21 months 120 patients were included, 46 % of them belong to the HR group. Mobilization is by July 2020 performed for 101 (84%) patients with cyclophosphamide (Cy) + G-CSF in 74% and G-CSF alone in 26%. Plerixafor was needed in 32 (32%) patients. The median number of harvesting days was 2 (0-4) and the median number of collected CD34+ cells was 6.4 (0-19.2) x 106/kg. Four patients (4%) failed to mobilize during 1st attempt. Eighty-six (72%) patients have so far received ASCT with the median number of 3.4 x 106/kg CD34+ cells in graft. Overall response rate is 93%. The responses after IRD x 4 induction and before consolidation are presented in Table 1. Before consolidation 10 patients (8%) are out of study due to PD and 4 (3%) have been withdrawn due to toxicity. Toxicity events included hypersensitivity with hepatorenal failure, grade 3 cytopenia with liver toxicity and one unexplained encephalitis. One patient was withdrawn due to Cy toxicity. Eight additional patients are withdrawn from study, 7 by physician´s decision and 1 by patient´s decision. All these 7 patients had high tumor burden based on paraprotein level either in serum (53 - 102 g/L) or in 24h urine (7.8 - 23.2 g/24h) and achieved only stable disease (SD) during induction. Fifty-eight grade 3-4 SAE reports from 39 (33%) patients have been received and 57% of these were infections. Three patients had grade 3 liver problems and 2 patients grade 3 peripheral neuropathy. Seventeen (14%) patients have reported skin reactions, only 4 of them grade 3 events. Conclusion We present here data on response and safety after observation of all patients until post-induction phase and of 87 % of the patients until start of the consolidation phase. The ORR is 93% when all patients have received induction treatment. Nine patients achieved only SD and seven of them with high tumor burden were withdrawn before mobilization. At least VGPR after ASCT was achieved in 37%. Toxicity caused the withdrawal of 4 (3%) patients and 39 (33%) patients have reported grade 3-4 non-hematological SAEs. In all, 98/120 (82%) patients continue in the study including 80% of the HR patients. Disclosures Silvennoinen: BMS: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Cancer patients Finland: Honoraria; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Research Funding. Waage:Janssen: Consultancy, Honoraria, Speakers Bureau; Takeda: Consultancy; Shire: Honoraria. Schjesvold:Celgene, Amgen, Janssen, Oncopeptides: Research Funding; Amgen, Celgene, Janssen, MSD, Novartis, Oncopeptides, Sanofi, SkyliteDX, Takeda: Honoraria; Amgen, Celgene, Janssen, MSD, Novartis, Oncopeptides, Sanofi, Takeda: Consultancy. Anttila:Sanofi: Research Funding; Amgen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; BMS: Research Funding; Janssen: Honoraria, Other: Advisory Board; Takeda: Honoraria, Research Funding. Säily:Amgen: Honoraria; Abbvie: Honoraria; Celgene: Honoraria; Roche: Honoraria; Sanofi: Honoraria; Pfizer: Honoraria; Takeda: Honoraria; Janssen Cilag: Honoraria; Boehringer Ingelheim: Honoraria. Sankelo:Celgene, Amgen, Sanofi: Other: Congress travel support. Partanen:Abbvie: Honoraria, Other: Scientific Advisory Board Meeting; Behring: Honoraria; Takeda: Other: Scientific Advisory Board Meeting.

Introduction. Bcl-2 family proteins comprise anti-apoptotic and pro-apoptotic proteins. Interaction between these proteins, as well as severe regulation of their expression, mediates cell survival and can quickly induce cell death. Venetoclax is Bcl-2-targeting that has shown preclinical and clinical activity in hematologic malignancies. Due to the development of resistance and the loss of dependence on the target protein, the monotherapy may be insufficient for maximal effectiveness. To circumvent the resistance mechanisms, many preclinical studies have shown that combination of venetoclax with other agents may represent a more effective therapeutic strategy. Ubiquitin-proteasome signaling pathway is a potential target that plays an important role in the proteolysis of key regulatory proteins. Proteasome inhibitors include ixazomib that inhibits cell growth and induces apoptosis in hematological malignancies cells resistant to conventional therapies and bortezomib. Objective: To analyze the preclinical efficacy and associated biological effects of venetoclax combined with ixazomib in a panel of lymphoma cell lines with diverse expression levels of Bcl-2 and other Bcl-2 family proteins. Methods: 12 lymphoma cell lines including FL (RL, WSU-NHL, Karpas422), MCL (Jeko1, Granta519), DLBCL (OCI-LY3, OCI-LY18), CTCL (Hut-78), ALCL (Karpas299), HL (L1236, L540), CLL (Mec1) and two MCL primary patient samples were exposed to venetoclax (0.01 - 8 µM) and ixazomib (10 - 2000 nM) alone for 24 - 72 hours to calculate IC50. Subsequently, lymphoma cells were exposed to venetoclax (0.015 - 25 nM) in combination with ixazomib (0.015 - 0.5 nM) for 24 hours. Cell viability was determined by MTT. Coefficient of synergy (combination index - CI) was calculated using CalcuSyn. Cell cycle and induction of apoptosis were evaluated by flow cytometry and changes in Bcl-2 family members, caspase activation and AKT phosphorylation were determined by western blotting. Results. In vitro, venetoclax and ixazomib alone induced cell death in a dose- and time-dependent manner against lymphoma cell lines. The IC50 is between 0.5 and 8 µM for venetoclax and between 12 and 1250 nM for ixazomib. The combination of venetoclax (0.03, 0.06, 12.5, 25 nM) with ixazomib (0.03, 0.06, 0.25, 0.5 nM) produced a synergistic effect (CI < 1) after 24 h of treatment in the most lymphoma cells lines leading to inhibition of cell growth and induction of apoptosis between 26 % and 59 % accompanied by increased with cleavage of caspases-3, -9 and PARP. We observed an additive effect (CI = 1) in Jeko1 (MCL) and MEC1 cells (CLL) and antagonist effect (CI > 1) Hut-78 cells (CTCL). Synergistic effect has been seen in two MCL primary patient samples (CI = 0.5 - 0.7). In sensitive lymphoma cells, the combination abrogated colony formation in the methylcellulose medium. When lymphoma cell lines were co-cultured with mesenchymal stromal cells with both drugs we observed a decrease of cell viability and a fraction of apoptotic cells indicating that drug combination may overcome the tumor promoting effects of stromal cells. The apoptosis induced in FL and Granta519 cells (MCL) by drug combination was accompanied by partial downregulation of Bcl-2 and strong upregulation of Bax, Bad, Bim and Noxa proteins. Jeko-1 cells were less sensitive to venetoclax-ixazomib combination-induced apoptosis. Western blot analysis showed a differential expression of Bcl-2, Mcl-1 and Bcl-XL proteins in FL, MCL and HL cell lines. Jeko-1 cells showed a normal expression of Bcl-2 and Mcl-1 proteins and high Bcl-xL protein level. Co-expression of related anti-apoptotic Bcl-2 family proteins could limit activity of treatment. Combined treatment induced G0/G1 cell cycle arrest and increased the sub-G1 population that was linked by the upregulation of p27 and p21. In addition, in RL, WSU-NHL and Granta519, enhanced cell death is associated with AKT inactivation and with a reduction of p-4EBP1, leading to decreased levels of c-MYC. Conclusion. Venetoclax exhibits strong synergistic activity with ixazomib in lymphoma cells. Studies are still ongoing and signaling pathways that promote the combination of venetoclax with ixazomib are to be analyzed. These data offer a rationale to continue exploring venetoclax-ixazomib combination and suggest that suppression of Bcl-2 family protein driven survival signaling may be one important mechanism for combination synergy. Disclosures No relevant conflicts of interest to declare.

INTRODUCTION. Elderly patients (pts) with newly diagnosed multiple myeloma (NDMM) are a heterogeneous population. The IMWG frailty score stratifies pts ≥65 years into 3 categories (fit, intermediate-fit and frail), according to chronological age, comorbidities and functional abilities, with different prognosis. We previously reported results from the phase II EMN10-Unito study investigating 4 Ixazomib-based induction regimens followed by Ixazomib maintenance in elderly NDMM pts. Here we present a post-hoc analysis of safety and efficacy of ixazomib-based induction regimens and maintenance according to IMWG frailty score. METHODS. NDMM, transplant-ineligible pts ≥65 years were enrolled. Treatment consisted of 9 induction cycles of Ixazomib combined with dexamethasone (Id), Cyclophosphamide-dexamethasone (ICd), Thalidomide-dexamethasone (ITd) or Bendamustine-dexamethasone (IBd), followed by single-agent Ixazomib maintenance for up to 2 years. Pts were stratified into 3 groups (fit, intermediate-fit and frail) according to IMWG frailty score. The aim of this analysis was to evaluate the efficacy (TTP, PFS, PFS2 and OS) and safety of ixazomib-based induction regimens and single-agent ixazomib maintenance in the 3 patient subgroups. RESULTS. 171 pts were enrolled in the study and started treatment; of these, 75 (44%) were classified as fit, 53 (31%) as intermediate-fit and 43 (25%) as frail. As expected, the median age was higher in frail (79 years) as compared with fit (71 years) and intermediate-fit (76 years) pts, and a worse ECOG score (1-2) was reported in frail (67%) as compared with fit (46%) and intermediate-fit pts (46%). Frail pts were also more likely to have ISS 2-3 myeloma (82%) compared with fit (59%) and intermediate-fit (77%) ones. The median follow-up for the entire population was 27 months. The ORR and VGPR rates after the induction were similar in fit (71%; 42%), intermediate-fit (74%; 38%) and frail pts (76%; 40%), although fit (8%) and intermediate-fit (13%) pts were more likely to achieve a CR than frail ones (2%). No significant differences in median PFS were observed among fit (14.1 months; HR: 0.75, p=0.27), intermediate-fit (14.8, HR: 0.68, p=0.12) as compared to frail pts (12.2 months). The median PFS2 was significantly longer in fit (41.1, HR: 0.48; p=0.04) and intermediate-fit (35.6, HR: 0.47, p=0.03) in comparison with frail pts (28.6 months). OS was longer in fit pts (NR; HR: 0.36, p=0.02) and intermediate-fit (NR; HR: 0.58, p=0.15) as compared to frail ones (36.7 months). The rates of grade 3-4 adverse events (AEs) and grade 3-4 non-hematological AEs during the induction phase were higher in frail pts (47% / 37%) as compared to fit (28% / 24%) and intermediate-fit (32% / 26%) ones. Similarly, the risk of treatment discontinuation was higher in frail (21%) as compared to fit (11%) and intermediate-fit pts (9%). When comparing PFS with three- vs two-drug ixazomib-based induction, both fit (HR: 0.75) and intermediate-fit (HR: 0.69) pts benefited from the use a triplet over a doublet; whereas, no difference between three- and two-drug combinations was observed in frail pts (HR: 1.01). Overall, 102 pts (60%) completed the induction phase and proceeded to ixazomib maintenance: of these, 46 (45%) were fit, 35 (34%) intermediate-fit and 21 (21%) frail. The median PFS from start of maintenance in the overall population was 15 months, without significant differences in intermediate-fit (HR: 0.92) and frail (HR: 1.14) pts as compared to fit ones. Concerning the safety of ixazomib maintenance, grade 3-4 non-hematological AEs were infrequent, occurring in 15% of fit pts (15%), 3% of intermediate-fit and 5% of frail (5%) ones. Ixazomib dose reductions were more frequent in frail (24%) as compared to fit (13%) and intermediate-fit (11%) pts, although a similar percentage of pts discontinued ixazomib due to AEs in the three groups (fit: 11%; intermediate-fit: 15%; frail: 10%). CONCLUSIONS. Ixazomib-based regimens had similar efficacy in terms of ORR and PFS, irrespective of frailty status, although AEs, dose modifications and treatment discontinuation were more frequent in frail pts. Importantly, frail pts did not seem to benefit from the addition of a third drug over the use of a doublet induction therapy. Single-agent ixazomib maintenance was effective and well tolerated in fit, as well as in intermediate-fit and frail pts, thus representing an appealing maintenance option in elderly MM. Disclosures Mina: Takeda: Honoraria; Celgene: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria. Larocca:Amgen: Honoraria; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria; Takeda: Membership on an entity's Board of Directors or advisory committees. Offidani:Celgene: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Janssen: Consultancy, Honoraria. Galli:BMS: Honoraria; Celgene: Honoraria; Janssen: Honoraria; Takeda: Honoraria. De Sabbata:Celgene: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Cavo:Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel accomodations, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Karyopharm: Honoraria; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel accomodations, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Boccadoro:Mundipharma: Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Research Funding; AbbVie: Honoraria; GlaxoSmithKline: Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Bringhen:Bristol-Myers Squibb: Honoraria; Takeda: Consultancy; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees. OffLabel Disclosure: The presentation includes discussion of off-label use of a drug or drugs for the treatment of multiple myeloma (including ixazomib, dexamethasone, cyclophosphamide, thalidomide and bendamustine).

INTRODUCTION: Lenalidomide and Rituximab (R2) is an effective frontline treatment regimen for patients (pts) with indolent B-cell lymphoma including follicular lymphoma (FL). Recent phase III data from the RELEVANCE trial comparing R2 to traditional chemoimmunotherapy showed that this regimen is generally well-tolerated and has favorable clinical efficacy [61% overall response, 53% CR rate, 77% 3-year progression free survival (PFS) (Morschhauser, et al)]. Proteasome inhibitors such as bortezomib disrupt NF-KB signaling and have shown clinical activity in indolent NHL. Although randomized trials have failed to demonstrate clinical benefit of adding bortezomib to standard chemoimmunotherapy regimen bendamustine + rituximab (BR) for frontline treatment of FL, the addition of proteasome inhibitors to lenalidomide is a mainstay of treatment for plasma cell neoplasms due to synergistic antitumor effect. The oral proteasome inhibitor ixazomib has less potential for dose-limiting neuropathy than bortezomib, making it an attractive option to incorporate into the R2 regimen. We sought to investigate the safety and efficacy of the addition of ixazomib to R2 for FL and indolent B-cell NHL through a phase I clinical trial of this combination for patients with high risk disease. METHODS: Adult (age ≥ 18) pts with untreated FL or other indolent lymphoma, adequate organ function and performance status were enrolled. To be enrolled, FL patients were required to have stage 2, 3 or 4 disease, with high tumor burden by GELF criteria and/or FLIPI score of 3-5. During 3 x 3 dose escalation, ixazomib was given at a dose of 2 mg (n=3), 3 mg (n=3) or 4 mg (n=12) PO on days 1, 8, and 15 with lenalidomide 20 mg PO on days 1-21 every 28 days. Rituximab was administered at standard dosing on days 1,8,15,21 for cycle 1, once every 28 days for cycles 2-6 and then once every 2 months for cycles 7-12. Treatment was continued for 12 cycles and no maintenance therapy was specified per protocol. All pts received low dose aspirin for venous thromboembolism prophylaxis and acyclovir for prevention of VZV reactivation. Response assessments by CT were performed after cycle 3 and 6 and by PET/CT at the end-of-treatment (cycle 12). RESULTS: 20 pts were enrolled and 18 were eligible for treatment [15 FL (14 grade 1-2, 1 grade 3A), 2 splenic marginal zone lymphoma and 1 nodal marginal zone lymphoma].The median age of treated pts was 61 (range 40-83) years old. 55% of patients were female. Stage at diagnosis was II (n =2), III (n = 4) and IV (n = 12). For FL pts, FLIPI scores at enrollment were low (n=2), intermediate (n = 5) and high risk (n=8) and FLIPI-2 scores were low (n=3), intermediate (n = 2) and high risk (n=10). There were no dose limiting toxicities during 3 x 3 dose escalation. Grade (G) 1/2 and G3/4 treatment-related hematologic adverse events (AEs) included neutropenia (6%, 28%), thrombocytopenia (16.7%, 5.6%) and anemia (16.7%, 0%). The most common treatment-related AEs included nausea/vomiting (44% G1, 11% G2), diarrhea, (50% G1, 22% G2, 5% G3), rash (33% G1, 6% G2, 11%G3), peripheral neuropathy (22% G1, 6% G2), myalgia/arthralgia (17% G1, 17% G2), and infection (33% G2, 17% G3). There was one pulmonary embolism and no cases of febrile neutropenia. As of June, 2020, median follow-up among living pts was 21 months. 4 pts discontinued treatment due to disease progression; 2 with transformation to aggressive lymphoma. Of the transformed cases, one subject died on study due to progression disease and one developed CNS disease on study treatment but proceeded to autologous stem cell transplant. The best overall response rate was 61.2% [55.6% CR, 5.6% PR): 22.2% had stable disease and 16.7% had disease progression. 18-month Kaplan-Meier estimates of PFS and overall survival were 71% and 94%, respectively (Figure). CONCLUSION: R2 can safely be combined with at the target dose of 4 mg of ixazomib for treatment-naïve indolent NHL patients. Non-hematologic AEs were generally consistent with known toxicity of each component of therapy. CR rate and PFS were was similar to the outcomes reported in the RELEVANCE trial despite enrolling high risk patient. R2 may serve as backbone for future studies of novel treatment combinations for high risk FL after thorough evaluation for occult transformation to aggressive lymphoma. Disclosures Hill: Abbvie: Consultancy, Honoraria, Research Funding; Genentech: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria; BMS: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Takeda: Research Funding; Karyopharm: Consultancy, Honoraria, Research Funding; AstraZenica: Consultancy, Honoraria, Research Funding; Kite, a Gilead Company: Consultancy, Honoraria, Research Funding; Beigene: Consultancy, Honoraria, Research Funding; Pharmacyclics: Consultancy, Honoraria, Research Funding. Jagadeesh:MEI Pharma: Research Funding; Regeneron: Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Debiopharm Group: Research Funding; Verastem: Membership on an entity's Board of Directors or advisory committees. Caimi:Celgene Corp: Other: Incyte Corporation - Ownership - Pharmacyclics, Inc. - Ownership - Celgene Corp. - Other, Speakers Bureau; ADC Therapeutics: Research Funding; Genentech: Research Funding. Smith:Takeda: Research Funding; Celgene: Research Funding. OffLabel Disclosure: Ixazomib is off-label for treatment of NHL

INTRODUCTION. The proteasome inhibitor (PI) Ixazomib, approved for the treatment of relapsed/refractory multiple myeloma (MM), represents an appealing option for the management of elderly patients, due to its oral administration and the lack of peripheral neuropathy. We previously presented preliminary results of the phase II EMN10-Unito study investigating Ixazomib in combination with dexamethasone (Id), Cyclophosphamide-dexamethasone (ICd), Thalidomide-dexamethasone (ITd) or Bendamustine-dexamethasone (IBd) as induction therapy followed by single-agent Ixazomib maintenance in transplant-ineligible newly diagnosed (ND) MM patients. Here we present updated results of the study with a longer follow-up. METHODS. Transplant-ineligible NDMM patients ≥65 years were enrolled. Treatment consisted of 9 28-day induction cycles of Ixazomib 4 mg on days 1,8,15 and dexamethasone 40 mg on days 1,8,15,22 or Id plus either Cyclophosphamide 300 mg/m2 orally on days 1,8,15 or Thalidomide 100 mg/day or Bendamustine 75 mg/m2 iv on days 1,8; followed by Ixazomib maintenance (4 mg on days 1,8,15) for up to 2 years. The primary endpoint was the selection of the most effective induction regimen considering a 2-year progression-free survival (PFS) ≥65% as satisfactory; secondary endpoints were very good partial response (VGPR), PFS2, overall survival (OS) and adverse events (AEs) during induction and maintenance. RESULTS. 171 patients (Id 41, ICd 59, ITd 60 and IBd 11) with a median age of 74 years were enrolled and started treatment. Two of the four investigational arms were prematurely closed due to low-enrollment (IBd arm, 11 patients enrolled) and high risk of inefficacy (Id, 41 patients enrolled). Median follow-up was 27 months. After the induction phase, ICd and ITd resulted in higher ≥ PR (75%-84% vs. 57%; p Overall, 102 patients (60%) completed the induction phase and proceeded to ixazomib maintenance (median follow-up from start of maintenance: 18 months). The best response during maintenance was PR in 26%, VGPR in 29%, and complete response (CR) in 26% of patients; 18% of patients improved the response obtained during induction by at least one IMWG category. The median PFS from start of maintenance was 15 months. The median duration of maintenance was 12 months. All grades AEs occurred in 39% of patients during maintenance, while grade 3-4 AEs occurred in 10% of patients. Grade 1-2 peripheral neuropathy (PN) was reported in 15% of patients, without grade 3-4 events. Overall, 15% required at least one dose reduction of ixazomib and 12% discontinued ixazomib maintenance due to AEs. CONCLUSIONS. Safety and efficacy data suggest that Id combined with cyclophosphamide was the most promising induction strategy compared to the other investigated combinations. Continuous treatment with single-agent Ixazomib confirmed its efficacy and tolerability in elderly NDMM patients. Disclosures Mina: Amgen: Honoraria; Celgene: Honoraria; Takeda: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Larocca:GSK: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria; Takeda: Membership on an entity's Board of Directors or advisory committees. Corradini:KiowaKirin: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Sanofi: Consultancy, Honoraria; Servier: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Other; BMS: Other; Kite: Consultancy, Honoraria; Gilead: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Daiichi Sankyo: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Incyte: Consultancy; Celgene: Consultancy, Honoraria, Other: Travel and accommodations paid by for; F. Hoffman-La Roche Ltd: Consultancy, Honoraria. Liberati:CELGENE: Honoraria; BIOPHARMA: Honoraria; ARCHIGEN: Honoraria; BEIGENE: Honoraria; BMS: Honoraria; AMGEN: Honoraria; FIBROGEN: Honoraria; INCYTE: Honoraria; VERASTEM: Honoraria, Research Funding; ROCHE: Honoraria, Research Funding; PFIZER: Honoraria, Research Funding; ONCOPEPTIDES AB: Honoraria, Research Funding; TAKEDA: Honoraria, Research Funding; MORPHOSYS: Honoraria, Research Funding; ONCONOVA: Honoraria, Research Funding; ABBVIE: Honoraria, Research Funding; NOVARTIS: Honoraria, Research Funding; KARYOPHARM: Honoraria, Research Funding; JANSSEN: Honoraria. Zambello:Celgene: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees. Belotti:Amgen: Membership on an entity's Board of Directors or advisory committees; Jannsen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Boccadoro:Sanofi: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; AbbVie: Honoraria; Mundipharma: Research Funding; GlaxoSmithKline: Membership on an entity's Board of Directors or advisory committees. Bringhen:Takeda: Consultancy; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. OffLabel Disclosure: The presentation includes discussion of off-label use of a drug or drugs for the treatment of multiple myeloma (including ixazomib, dexamethasone, cyclophosphamide, thalidomide and bendamustine).

Introduction: Multiple myeloma is an incurable hematologic malignancy. However, many novel drugs (lenalidomide, carfilzomib, daratumumab, elotuzumab and ixazomib) have recently been approved in Brazil for this disease. Proving that the availability of these drugs increases survival is not straightforward, since pivotal trials with these drugs were designed to show benefit in progression-free survival and not in overall survival. Hypothesis: We have hypothesized that the availability of novel drugs would reduce the risk of death. Methods: This is a real-world, unicenter analysis that included patients with multiple myeloma treated between 1993 and 2017. The availability of novel drugs (lenalidomide, carfilzomib, daratumumab, elotuzumab and ixazomib) was treated as a time-dependent covariate and analyzed by Cox model. The analysis was controlled for the International Staging System (ISS) and for age. Results: With a median follow-up of 6 years, we included 151 patients with multiple myeloma. Fourty percent had ISS-I, 34% ISS-II and 26% ISS-III. Mean age was 60.5 y/o (SD: 12.2). There has been 51 deaths, and 5-y overall survival was 90% for ISS-I, 80% for ISS-II and 54% for ISS-III (p=0.0004). In multivariable analysis, age (HR=1.06, p Discussion: Our results show that the availability of two or more novel drugs increases overall survival in multiple myeloma. This is an important finding, since the pivotal trials were designed to show advantages in progression-free survival and, once achieved, the experimental drug was offered to the control group, hampering overall survival analyses. Overall survival benefit, therefore, are more likely to be seen in real-world studies. We included the availability of novel drugs as a time-dependent, and the interpretation of our results is that patients alive when two novel drugs became available had benefit in overall survival. Our study has two weaknesses. Two or more novel drugs were more likely to be available for patients from a more recent time. This difference could be due to changes in supportive care, but there has been no major change in supportive care for multiple myeloma patients. Another weakness is that patient alive in the more recent years may have not received novel drug-based treatment. Considering that multiple myeloma is an incurable disease, this is unlikely for the majority of patients. In conclusion, the availability of two or more novel drugs for multiple myeloma improves survival. Figure Disclosures No relevant conflicts of interest to declare.

Background: The combination of a proteasome inhibitor (PI), an immunomodulatory drug (IMiD), and dexamethasone is the current standard induction therapy for myeloma. Daratumumab (Dara), a monoclonal antibody directed against CD38, is highly effective in treating myeloma and improves response rates and progression free survival (PFS) when added to PI or IMiD. Ixazomib, lenalidomide and dexamethasone (IRd) is an effective, all oral, induction regimen that has been studied in phase 2 and 3 trials. We designed this trial to examine the feasibility and efficacy of adding daratumumab to the IRd regimen as well as early discontinuation of dexamethasone in two sequential cohorts of patients. Patients and Methods: Patients with previously untreated MM who had measurable disease and adequate organ function were enrolled, irrespective of their autologous stem cell transplant eligibility. The primary objective was to determine the rate of complete response to IRD-Dara combination. A one-stage binomial design was utilized in each cohort independently to test the null hypothesis that the complete response rate is at most 25% against the alternative hypothesis that it is at least 45%, with 89% power and 9% type I error. Treatment involved 28-day cycles consisting of ixazomib 4 mg days 1, 8, 15; lenalidomide 25 mg days 1-21, dexamethasone 40 mg, weekly and Dara 16 mg/kg, weekly for two cycles, every other week during cycles 3-6 and then every 4 weeks thereafter during induction (12-cyles) followed by Dara-ixazomib maintenance (maximum 24 cycles). Cohorts A (n=38) and B (N=40) comprised the study population, with dexamethasone discontinued after two cycles in Cohort B. Results: Baseline demographics and patient disposition are outlined in the table. Among those who have gone off study, 9 and 5 patients, respectively in Cohort A and B went off for progression, while 11 and 8 patients in the respective arms discontinued treatment for an alternative therapy, most frequently a transplant. Responses were rapid and deepened over the duration of treatment as shown in the figure; 32% of patients in Cohort A and 28% of patients in Cohort B achieved a complete response; 29% and 23%, respectively, achieved a marrow minimal residual disease (MRD) negative status. After a median follow up was 31.4 months for Cohort A and 18.2 months for Cohort B, median PFS has not been reached in either cohort. A grade 3 or higher adverse event at least possibly attributed to the study drugs was seen in 58% of patients in Cohort A (hematologic in 47% and non-hematologic in 26%) and 50% of patients in Cohort B (hematologic 43%, non-hematologic 20%). The most common toxicities included fatigue, neutropenia, lymphopenia, peripheral neuropathy and nausea. Stem cells were collected in 30 and 31 patients in Cohorts A and B respectively; median (range) of CD34 cells/kg were 8.5 (2.8, 15.9) x 106and 7.0 (2.9, 12.1) x 106, with plerixafor used in 83% and 94% of patients, respectively, in Cohorts A and B as per our standard of care "on-demand" approach based on blood CD34 count. Conclusion: Dara-IRd is an active regimen in newly diagnosed MM, with high overall rates of response and deep responses that improved over time with therapy. Early discontinuation of dexamethasone does not appear to impact the depth, rate or kinetics of response. The toxicities were manageable, with dose modifications. All patients were able to collect stem cells when required, though majority needed plerixafor. Disclosures Kumar: Amgen: Consultancy, Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments, Research Funding; Kite Pharma: Consultancy, Research Funding; Carsgen: Other, Research Funding; Janssen Oncology: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Cellectar: Other; Dr. Reddy's Laboratories: Honoraria; Takeda: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; AbbVie: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Celgene/BMS: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Merck: Consultancy, Research Funding; Adaptive Biotechnologies: Consultancy; Tenebio: Other, Research Funding; Oncopeptides: Consultancy, Other: Independent Review Committee; IRC member; Genentech/Roche: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Genecentrix: Consultancy; Sanofi: Research Funding; Novartis: Research Funding; MedImmune: Research Funding; Karyopharm: Consultancy; BMS: Consultancy, Research Funding. Kapoor:GlaxoSmithKline: Research Funding; Celgene: Honoraria; Takeda: Honoraria, Research Funding; Amgen: Research Funding; Sanofi: Consultancy, Research Funding; Janssen: Research Funding; Cellectar: Consultancy. Dingli:Apellis: Consultancy; Karyopharm Therapeutics: Research Funding; Janssen: Consultancy; Bristol Myers Squibb: Research Funding; Alexion: Consultancy; Rigel: Consultancy; Millenium: Consultancy; Sanofi-Genzyme: Consultancy. Dispenzieri:Pfizer: Research Funding; Takeda: Research Funding; Alnylam: Research Funding; Janssen: Research Funding; Celgene: Research Funding; Intellia: Research Funding. Gertz:Abbvie: Other; Sanofi: Other; Celgene: Other; Research to Practice: Other; Physicians Education Resource: Other: personal fee; Amgen: Other: personal fee; Medscape: Other: personal fee, Speakers Bureau; Appellis: Other: personal fee; Annexon: Other: personal fee; Alnylam: Other: personal fee; Spectrum: Other: personal fee, Research Funding; Janssen: Other: personal fee; Teva: Speakers Bureau; Aurora Bio: Other; Springer Publishing: Patents & Royalties; Proclara: Other; DAVA oncology: Speakers Bureau; Johnson and Johnson: Speakers Bureau; Ionis/Akcea: Other: personal fee; Prothena: Other: personal fee.

Background: Multiple myeloma is typically characterized by clonal expansion of malignant plasma cells within the bone marrow compartment. Presence of extramedullary disease (EMD) either in the form of soft tissue plasmacytoma or circulating plasma cells can be seen at diagnosis but is more common in the relapsed and refractory patients. Presence of EMD is typically associated with a poor prognosis, both in the newly diagnosed and relapsed setting, but trials designed specifically for patients with EMD are sparse. Treatment of EMD can be challenging and the responses even when seen are often short lasting, highlighting the need for developing specific treatment approaches aimed at these patients. Based on initial trials suggesting activity of pomalidomide in the setting of EMD and the increased tissue distribution with the oral proteasome inhibitor ixazomib, we designed this trial to examine if the all oral combination of ixazomib, pomalidomide and dexamethasone can be effective in the setting of EMD. Patients and Methods: Patients with previously treated multiple myeloma, with adequate hematologic and organ function were enrolled if there was evidence, at study entry, of EMD defined as one or more plasmacytomas, outside the bone marrow that were non-contiguous with a bone lesion and had a single diameter of ≥2 cm OR as plasma cell leukemia, with circulating plasma cells > 5% of peripheral blood leukocytes or at least 0.5 X 109/L or 200 cells/150000 events by flowcytometry. Patients were treated on 28-day cycles, with ixazomib 4 mg on days 1, 8, and 15 along with pomalidomide 4 mg PO daily on days 1-21 and dexamethasone 40 milligrams weekly until disease progression or unacceptable toxicity. The goals of the study were to determine confirmed response rate (≥ PR), toxicities of this combination, differential response rates and progression-free survival (PFS). Confirmed response rate, differential response rates and PFS were estimated using Duffy and Santner approach, exact binomial distributions and Kaplan Meier curves, respectively. The study was designed to accrue 30 patients. Results: This study was designed to enroll up to 30 patients but was closed after enrolling 17 patients due to slow accrual. The baseline characteristics are as indicated in Table 1. Eleven patients were enrolled with an extramedullary plasmacytoma while the remaining six patients had plasma cell leukemia. Median number of lines of prior therapy was 3 (range: 1, 7). Overall, 10 (58.8%) patients had progressive disease and 11 (64.7%) patients have died, median (range) follow-up for the live patients is 22.2 (2.1, 37.9) months. Patients were treated for a median of 2 (range 1-34) cycles. A grade 3+ AE, at least possibly attributed, was seen in 53%. Grade 3+, at least possibly related, hematologic toxicity was noted in 41%, with 29% experiencing grade 3+ neutropenia. Notable grade 3+ non-hematologic toxicities (regardless of attribution), with >10% incidence rate were anemia, hypoxia, infections and lung infection. The confirmed response rate in evaluable patients was 35% (1 CRs and 5 PRs), with a 90% CI of 6% - 37%. While 33% (4/12; 95% CI: 1-8%) of patients reported a biochemical response, 40% (2/5; 95% CI: 0-4%) of patients reported an extramedullary response. The median PFS was 4.5 (95% CI: 2-11.8) months. Conclusions: The combination of ixazomib, pomalidomide and dexamethasone resulted in disease response in a third of this group of high-risk patients with EMD; however, the responses were not very durable, with a median PFS of only 4.5 months. The trial highlights the feasibility of doing clinical trials specifically targeted towards this high-risk patient population. Future trials should explore combinations of novel agents, including monoclonal antibodies through multicenter collaborative efforts. Disclosures Kansagra: Alnylam Pharmaceuticals, Bristol Myers Squibb /Celgene, GlaxoSmithKline, Janssen, Pharmacyclics, Takeda Pharmaceuticals, Pfizer, Karyopharm Therpeutics: Other: Advisory Board. Witzig:Spectrum: Consultancy; Immune Design: Research Funding; Karyopharm Therapeutics: Research Funding; Acerta: Research Funding; Incyte: Consultancy; AbbVie: Consultancy; MorphSys: Consultancy; Celgene: Consultancy, Research Funding. Kumar:Oncopeptides: Consultancy, Other: Independent Review Committee; IRC member; Genecentrix: Consultancy; Carsgen: Other, Research Funding; Cellectar: Other; Celgene/BMS: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Dr. Reddy's Laboratories: Honoraria; AbbVie: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Takeda: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Janssen Oncology: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Merck: Consultancy, Research Funding; Amgen: Consultancy, Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments, Research Funding; Kite Pharma: Consultancy, Research Funding; Novartis: Research Funding; Adaptive Biotechnologies: Consultancy; Genentech/Roche: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; BMS: Consultancy, Research Funding; Karyopharm: Consultancy; MedImmune: Research Funding; Sanofi: Research Funding; Tenebio: Other, Research Funding.

Background. GVHD is a frequent complication within the 1st year after allogeneic stem cell transplantation (allo-HCT). Recipients of reduced intensity (RI) and non-myeloablative (NMA) conditioning combined with calcineurin inhibitor (CNI)-based GVHD prophylaxis, frequently develop GVHD in the context of immunosuppression taper. Ixazomib is an oral proteasome inhibitor (PI) that has demonstrated immunomodulatory properties, inhibition of pro-inflammatory cytokines, anti-tumor activity, and has a wide safety profile. We hypothesized that secondary GVHD prophylaxis using ixazomib, will facilitate CNI taper without increase in GVHD frequency and severity, maintaining graft-versus-tumor (GVT) effect, and a safety profile. Methods. We conducted an open label, prospective, single-center pilot study between 11/16 and 03/19. Eligible patients were > 18 yrs old, had a hematologic malignancy treated with RI or NMA conditioning allo-HCT, received CNI-based GVHD prophylaxis, and were within day 100 to 150 post-HCT. Patients with active acute and/or chronic GVHD were excluded. Patients were treated with ixazomib 4 mg orally once weekly, each cycle consisting of 3 weeks on and 1 week off therapy, until completion of taper from prophylactic CNI or 1-year post-HCT was reached, whichever occurred first. Patients who developed grade II-IV acute GVHD, chronic GVHD, or died of transplant-related mortality (TRM) were deemed treatment failure. The primary endpoint was the efficacy of ixazomib for the prevention of recurrent or late grade II-IV acute GVHD or chronic GVHD at 1-year post-HCT. Additional endpoints included TRM, relapse rate, survival analysis, safety evaluation, and immune reconstitution. Results. A total of 18 patients (median age of 58 yrs) were accrued in the study. The majority were male, had a diagnosis of NHL, and received RI conditioning (Table 1). All patients had a PBSC graft, and 16 (89%) were 10/10 HLA-matched. The median time for initiation of ixazomib was 141.5 days post-HCT. Fourteen patients had no GVHD during the study period. The 4 patients who developed GVHD had severe overlap syndrome (n = 2), mild de novo chronic GVHD (n = 1), and recurrent grade II acute GVHD (n = 1). Notably, patients with severe overlap syndrome had limited chronic GVHD involvement affecting the mouth and/or eyes, and the severity score was driven by acute manifestations affecting the skin and GI tract. Six patients successfully discontinued CNI and 4 patients were tapering immunosuppression close to the end of study at 1-year post-HCT. The cumulative incidence (CI) of grade II-IV acute and chronic GVHD at 1-year post-HCT was 25% (95%CI: 7.2-48.1) (Fig. 1A). No patients died during the study and therefore, the CI of TRM at 1-year was 0%, and only 1 patient had malignant relapse (NHL). The CI of PFS and the composite endpoint GVHD-free/relapse-free survival (GRFS) at 1-year were 83% (95%CI: 58-100) and 73% (95%CI: 49-100, Fig 1B), respectively. All patients experienced at least 1 TEAE of any grade. Most AEs were grade 1 or 2, with the most common being cytopenia and elevation in ALT/AST. Drug-related SAEs were reported in 9 patients and included neutrophil and decreased WBC. Seven patients required ixazomib dose reduction due to side effects, and 5 patients were removed from the study due to toxicity (1 neutropenia, 3 GI, 1 skin rash). Of those, 1 had subsequent GVHD by day 365 post-HCT. Immune recovery at 3, 6 and 12 months post-HCT was evaluated. There was a rapid and sustained recovery in T-cell subpopulations and B cell reconstitution Fig 2. Conclusions. Secondary GVHD prophylaxis with ixazomib was associated with low incidence of recurrent and late acute and chronic GVHD within the 1st year post-HCT. This approach allowed CNI taper while preserving GVT effect without aggravating GVHD. No deaths occurred during the study period and the 1-year GRFS was high. Ixazomib was overall well tolerated and favored immune reconstitution post-HCT. Our findings support further development of this approach and provide a proof-of-concept for secondary GVHD prophylaxis. Disclosures Dahi: Kite: Consultancy. Giralt:TAKEDA: Research Funding; JAZZ: Consultancy, Honoraria; CELGENE: Consultancy, Honoraria, Research Funding; AMGEN: Consultancy, Research Funding; MILTENYI: Consultancy, Research Funding; KITE: Consultancy; NOVARTIS: Consultancy, Honoraria, Research Funding; OMEROS: Consultancy, Honoraria; ACTINUUM: Consultancy, Research Funding. Sauter:Bristol-Myers Squibb: Research Funding; GSK: Consultancy; Gamida Cell: Consultancy; Celgene: Consultancy, Research Funding; Kite - a Gilead Company: Consultancy; Precision Biosciences: Consultancy, Research Funding; Genmab: Consultancy; Novartis: Consultancy; Spectrum Pharamaceuticals: Consultancy; Sanofi-Genzyme: Consultancy, Research Funding; Juno Therapeutics: Consultancy, Research Funding. Perales:Omeros: Honoraria, Membership on an entity's Board of Directors or advisory committees; Medigene: Membership on an entity's Board of Directors or advisory committees, Other; NexImmune: Membership on an entity's Board of Directors or advisory committees; Servier: Membership on an entity's Board of Directors or advisory committees, Other; Cidara Therapeutics: Other; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Nektar Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Consultancy, Honoraria; Miltenyi Biotec: Research Funding; Kite/Gilead: Honoraria, Research Funding; Incyte Corporation: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; MolMed: Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria; Bellicum: Honoraria, Membership on an entity's Board of Directors or advisory committees. Ponce:Ceramedix: Membership on an entity's Board of Directors or advisory committees; Generon: Membership on an entity's Board of Directors or advisory committees; Kadmon: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding.

Introduction: Outcomes for acute myeloid leukemia (AML) among older patients has remained largely unchanged for decades. Long-term survival for patients aged >60 years is poor (median survival 10.5 months). Targeting the proteasome in AML is attractive, since leukemia stem cells have demonstrated sensitivity to proteasome inhibition in preclinical models, perhaps through down regulation of nuclear NF-KB (Guzman, Blood 2001). AML cell lines are susceptible to synergistic cytotoxicity when bortezomib, a proteasome inhibitor, is combined with daunorubicin and cytarabine. We have shown that adding bortezomib to standard treatment in AML results in a high remission rate, although grade 2 sensory neurotoxicity was noted in approximately 12% of treated patients. A newer generation proteasome inhibitor, ixazomib, is less frequently associated with neurotoxicity, and, therefore, was selected for combination with conventional chemotherapy in this phase I trial. The primary objective of this study was to determine the maximum tolerated dose (MTD) of ixazomib in combination with conventional induction and consolidation chemotherapy for AML. Herein are the initial results of this trial. Methods: Adults >60 years of age with newly diagnosed AML were screened for eligibility. Patients with secondary AML were eligible, including those with prior hypomethylating agent therapy for myelodysplastic syndromes (MDS). We excluded those with promyelocytic leukemia. There were 2 phases in this study. In the first phase (A), the induction treatment consisted of the following: cytarabine 100 mg/m2/day by continuous IV infusion, Days 1-7; daunorubicin 60 mg/m2/day IV, Days 1, 2, 3, and ixazomib was provided orally at the cohort dose, Days 2, 5, 9, and 12. Consolidaton or transplant was at the discretion of the treating physician in phase A. In the second phase (B), induction was the same as that with the determined MTD of ixazomib. All patients were to be treated with the following consolidation: cytarabine at 2 g/m2/day, days 1-5 with ixazomib on days 2, 5, 9, and 12 at the cohort dose for consolidation. A standard 3 + 3 patient cohort dose escalation design was used to determine whether the dose of ixazomib could be safely escalated in 3 cohorts (1.5 mg/day, 2.3 mg/day, 3.0 mg/day), initially in induction (phase A) and subsequently in consolidation (phase B). The determined MTD of ixazomib in the first portion (A) of the trial was used during induction in the second portion (B), which sought to determine the MTD for ixazomib during consolidation. Secondary objectives included rate of complete remission, disease-free survival, and overall survival (OS). Results: Thirty-six patients have been enrolled on study, and 28 have completed dose levels A-1 through A-3 and B1 through B-2. Full information on cohort B-3 has not yet been obtained, hence, this report covers the experience with the initial 28 patients, cohorts A-1 through B-2. There were 12 (43%) patients among the 28 with secondary AML, either with prior hematologic malignancy or therapy-related AML. Nineteen patients (68%) were male, and the median age was 68 years (range 61-80 years). There have been no grade 5 toxicities due to study drug. Three patients died early due to leukemia, 2 of which were replaced for assessment of the MTD. Nearly all the grade 3 and 4 toxicities were hematologic (Table). There was 1 DLT (grade 4 platelet count decrease extending beyond Day 42). There has been no grade 3 or 4 neurotoxicity with ixazomib to date. Among the 28 patients in the first 5 cohorts, 22 achieved complete remissions (CR) and 2 achieved CRi, for a composite remission rate (CCR) of 86%. Among the 12 patients with secondary AML 8 achieved CR and 2 achieved CRi, for a CCR of 83%. The median OS for the 28 patients has not been reached (graph). The 18-month OS estimate was 65% [90% CI, 50-85%]. Conclusions: The highest dose level (3 mg) of ixazomib planned for induction in this trial has been reached safely. For consolidation there have been no serious safety issues in the first 2 cohorts with a dose up to 2.3 mg, apart from 1 DLT in the form of delayed platelet count recovery. The recommended phase 2 dose of ixazomib for induction is 3 mg. Accrual to cohort B-3 is ongoing. Notably, to date, no grade 3 or 4 neurotoxicity has been encountered. The remission rate in this older adult population with the addition of ixazomib to standard chemotherapy appears favorable. Figure Disclosures Amrein: Amgen: Research Funding; AstraZeneca: Consultancy, Research Funding; Takeda: Research Funding. Attar:Aprea Therapeutics: Current Employment. Brunner:Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Forty-Seven Inc: Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Research Funding; Takeda: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding. Hobbs:Constellation: Honoraria, Research Funding; Novartis: Honoraria; Incyte: Research Funding; Merck: Research Funding; Bayer: Research Funding; Jazz: Honoraria; Celgene/BMS: Honoraria. Neuberg:Celgene: Research Funding; Madrigak Pharmaceuticals: Current equity holder in publicly-traded company; Pharmacyclics: Research Funding. Fathi:Blueprint: Consultancy; Boston Biomedical: Consultancy; BMS/Celgene: Consultancy, Research Funding; Novartis: Consultancy; Kura Oncology: Consultancy; Trillium: Consultancy; Amgen: Consultancy; Seattle Genetics: Consultancy, Research Funding; Abbvie: Consultancy; Pfizer: Consultancy; Newlink Genetics: Consultancy; Forty Seven: Consultancy; Trovagene: Consultancy; Kite: Consultancy; Daiichi Sankyo: Consultancy; Astellas: Consultancy; Amphivena: Consultancy; PTC Therapeutics: Consultancy; Agios: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; Jazz: Consultancy. OffLabel Disclosure: Ixazomib is FDA approved for multiple myeloma. We are using it in this trial for acute myeloid leukemia.

Background: Bortezomib, a proteasome inhibitor, has shown efficacy in the treatment of newly diagnosed and relapsed light chain (AL) amyloidosis, and the combination of bortezomib, cyclophosphamide and dexamethasone is a commonly used regimen in AL. Ixazomib is the first oral proteasome inhibitor to be approved, and the combination of ixazomib with cyclophosphamide and dexamethasone is an all oral effective regimen for the treatment of multiple myeloma. This phase 2 trial was designed to evaluate the efficacy of this regimen in patients with AL, who have not received any therapy. Patients and methods: Newly diagnosed patients with biopsy proven AL amyloidosis, with organ involvement requiring therapy, were enrolled if they had measurable disease (Serum immunoglobulin free light chain ≥5 mg/dL AND abnormal serum free light chain ratio) and adequate organ function. Patients with severe organ involvement were excluded (Alkaline phosphatase >750 U/L, creatinine clearance Results: Thirty-five patients were enrolled, median age was 67 (range 38-78) years; 69% were male. Organ involvement included cardiac in 23 (65.7%), renal in 19 (54.3%), and nervous system involvement in 5 (14.3%). At data cutoff 8 patients still remain on study with a median follow up of 4.4 months for those who are alive. Across the trial a median of 4 cycles (range 0-23) of treatment have been completed; the most common reason for going off study was institution of alternate therapy in 17 patients (63%). The overall hematologic response was 57% (20/35) and included amyloid CR in 5 (14%), VGPR in 9 (26%) and a PR in 6 (17%) patients. Confirmed organ responses have been observed in 5 patients so far, 2 each for cardiac and renal and 1 hepatic. The median PFS and OS have not been reached; 4 patients had hematological progression; 6 patients (17%) have died. Across 193 cycles of treatment administered, dose modification was required in 5, 3, and 10 patients, respectively, for ixazomib, cyclophosphamide and dexamethasone. A grade 3 or higher adverse event (AE), at least possibly attributed to the study drugs, was observed in 41% of patients. The figure shows the maximum grade of adverse events for individual patients seen in more than one patient across the study. Conclusions: The all-oral regimen of ixazomib, cyclophosphamide, and dexamethasone is active in patients with previously untreated AL amyloidosis with hematologic responses observed in 57% of patients, including complete responses. Organ response has been observed but will likely need longer follow up for accurate assessment, given the delay in organ responses in this disease. Further evaluation of this combination is warranted. Disclosures Gertz: Alnylam: Consultancy; Ionis/Akcea: Consultancy; Amgen: Consultancy; Medscape: Consultancy, Speakers Bureau; Physicians Education Resource: Consultancy; Data Safety Monitoring board from Abbvie: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy; Johnson and Johnson: Speakers Bureau; DAVA oncology: Speakers Bureau; Advisory Board for Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Advisory Board for Proclara: Membership on an entity's Board of Directors or advisory committees; i3Health: Consultancy; Springer Publishing: Patents & Royalties; Amyloidosis Foundation: Research Funding; International Waldenstrom Foundation: Research Funding; NCI SPORE MM: Research Funding; Prothena: Consultancy; Sanofi: Consultancy; Janssen: Consultancy; Spectrum: Consultancy, Research Funding; Annexon: Consultancy; Appellis: Consultancy. Kapoor:Celgene: Honoraria; GlaxoSmithKline: Research Funding; Takeda: Honoraria, Research Funding; Amgen: Research Funding; Sanofi: Consultancy, Research Funding; Janssen: Research Funding; Cellectar: Consultancy. Larsen:Janssen Oncology: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees. Dingli:Apellis: Consultancy; Janssen: Consultancy; Sanofi-Genzyme: Consultancy; Rigel: Consultancy; Bristol Myers Squibb: Research Funding; Karyopharm Therapeutics: Research Funding; Alexion: Consultancy; Millenium: Consultancy. Dispenzieri:Janssen: Research Funding; Intellia: Research Funding; Alnylam: Research Funding; Celgene: Research Funding; Pfizer: Research Funding; Takeda: Research Funding. Kumar:Adaptive Biotechnologies: Consultancy; Carsgen: Other, Research Funding; AbbVie: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Janssen Oncology: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Genecentrix: Consultancy; Dr. Reddy's Laboratories: Honoraria; Tenebio: Other, Research Funding; Takeda: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; BMS: Consultancy, Research Funding; Sanofi: Research Funding; Novartis: Research Funding; Kite Pharma: Consultancy, Research Funding; Karyopharm: Consultancy; Oncopeptides: Consultancy, Other: Independent Review Committee; IRC member; Merck: Consultancy, Research Funding; Amgen: Consultancy, Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments, Research Funding; Genentech/Roche: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Celgene/BMS: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Cellectar: Other; MedImmune: Research Funding.

The goal of treatment of relapsed/refractory multiple myeloma (RRMM) is to control the disease, prolong survival, reduce disease-related symptoms, and improve quality of life (QoL). Comprehensive evaluation of new treatment regimens in RRMM pts is worthwhile. We aimed to evaluate QoL, treatment satisfaction, response to treatment and safety during Ixazomib-Lenalidomide-Dexamethasone (IRd) treatment as ≥ 2nd line in RRMM pts in a real world setting. Adult pts with RRMM who have been assigned IRd as ≥2nd line treatment were enrolled in multicenter observational prospective study. Treatment response was evaluated by IMWG 2011, adverse events (AEs) - by CTCAE v.4.0. Pts filled out RAND SF-36 and ESAS-R at baseline and at 1 and 3 mos, and thereafter every 3 mos till 18 mos after IRd treatment start; Patient Treatment Satisfaction Cheklist (PTSC) - at each time-point after IRd treatment start. For analysis of meaningful QoL changes during IRd treatment the proportion of pts with baseline significant QoL impairment who experienced meaningful QoL improvement during IRd treatment was evaluated as well as the number of pts without baseline QoL impairment who maintained it during IRd treatment. For statistical analysis GLM paired test and GEE were employed with adjustment to age, gender and baseline QoL. In total, 40 pts with RRMM were enrolled into the pilot study: median age - 64 years (range, 33-80), 29% males, Durie-Salmon stage at study entry: I/II/III - 3/41/56%, ECOG status 0/1 - 68.7%, 2/3 - 31.6%. Median time since initial MM diagnosis - 51.4 mos (range, 2.9-100.7), disease status at study entry: relapsed - 26%, refractory - 21%, relapsed and refractory - 53%. Median number of lines of prior therapy is 3 (range, 1-3). At the time of analysis the median number of IRd cycles administered is 5, median follow-up - 4.6 (0.4-13.7) mos. Treatment response was not evaluated in 11 pts: 1 - death (at 3 months), 1- refusal, 9 - too early for evaluation. Out from 29 pts one patient achieved complete response (CR), seven pts achieved partial response (PR) and one patient - very good partial response (VGPR), 12 - minor response (MR). Thus, a clinical benefit rate was 70%. Also, seven pts achieved stable disease (23%), one patient was primary refractory to IRd (3.5%), one patient died (3.5%). At the time of analysis all the pts with CR/PR/VGPR (30%) maintained their response to treatment, 4 pts (13%) maintained stable disease and 9 pts (30%) maintained minor response; 7 pts (23%) experienced disease progression. AEs were revealed in 47% pts: grades 1-2 AEs - 12 pts; grades 3-4 AEs - 4 pts; SAEs - 3 pts (neurological toxicity, gastric bleeding, hypotension), all pts with SAEs discontinued IRd treatment. Baseline QoL was dramatically impaired by the majority of SF-36 scales with significant QoL impairment in 42% pts. The most worsening was revealed for physical functioning, role functioning, general health and vitality (Mean scores varied from 24.6 to 47.0 out from 100 scores). At baseline 88% pts had moderate-to severe symptoms (≥4 scores on the scale from 0 to 10); moderate-to severe worse wellbeing, tiredness, pain and shortness of breath had 72,5%, 67,5%, 61,5% and 45% pts, respectively. At 1 month of IRd treatment QoL meaningfully improved or was stable without significant impairment in 61% pts, at 3 months - in 50% pts. In 1 mos of IRd treatment significant improvement was revealed for physical functioning (GLM, 44.9 vs 54.7, p=.01) and general health (GLM, 47.8 vs 56.3, p.05). At 1 month of treatment, meaningful decrease of shortness of breath (in 42% pts), tiredness (36%), and pain (28%) was revealed; at 3 months of IRd treatment this proportion was 33%, 27%, and 13%, accordingly. Regarding treatment satisfaction pts reported the following: at 1 month after treatment start 94% of pts were satisfied with symptoms decrease due to IRd, 89% pts confirmed that IRd was convenient and 97% pts reported global satisfaction with IRd; at 3 months of treatment all the pts confirmed the convenience of IRd regimen, 84% pts were satisfied with IRd treatment. The results obtained in a real-world setting demonstrate clinical benefits of IRd regimen in RRMM pts, which were achieved without negatively affecting QoL and with satisfactory symptom control in these heavily pretreated patients. IISR funded by Takeda Disclosures Ionova: BMS: Research Funding; Takeda: Research Funding. Vinogradova:Novartis: Honoraria, Research Funding.

BACKGROUND: The human c-MYC oncogene is rearranged or overexpressed in approximately 12% or 37% of aggressive B-cell non-Hodgkin lymphomas (NHL), respectively. Relapses within 18-24 months are observed in more than 50% of these patients when treated with standard chemoimmunotherapy. Ixazomib is an orally bioavailable proteasome inhibitor that is FDA approved for multiple myeloma and has been shown to down-regulate MYC in lymphoma models (Ravi et al., 2016). It has also demonstrated preclinical activity in aggressive NHL, including double-hit (DH) lymphoma. Herein, we report results of a multicenter phase I/II study evaluating the safety and efficacy of induction chemotherapy with DA-EPOCH-R in combination with ixazomib followed by ixazomib maintenance in aggressive MYC-aberrant NHL. METHODS: Adult patients with aggressive MYC-aberrant NHL defined as MYC-overexpression (> 40%) by IHC, MYC-amplification (>4 copies) by FISH, and/or MYC-rearrangement by FISH were eligible. Ixazomib was administered in conjunction with 6 cycles of DA-EPOCH-R. Intrathecal methotrexate prophylaxis was administered using institutional guidelines. Ixazomib was continued as maintenance for up to one year in responders. During phase I, an accelerated titration design was employed to determine the MTD of ixazomib (doses of 2.3 mg, 3 mg or 4 mg) in combination with DA-EPOCH-R. During induction, ixazomib was administered twice per cycle (1 cycle = 21 day), day 1 and day 8 or 15 based on blood counts. For maintenance, ixazomib was dosed at 4 mg weekly. Based on phase I results, 3mg of ixazomib was chosen as the RP2D for phase II. The primary objective was to determine MTD in phase I and to evaluate the efficacy of ixazomib given with DA-EPOCH-R as measured by 12-month PFS rate in phase II. Secondary objectives were to evaluate safety and assess ORR post-induction and OS in all phase I/II patients. RESULTS: Thirty-eight patients were enrolled between 10/2015 and 9/2019 and 36 were evaluable for response. Median age was 63 years (range 31-77) and 27 were male (71%), 86% had advanced stage, 46% had DH or triple hit lymphoma (28% and 18%, respectively), and 89% had an IPI of 2 or higher (Table 1). Twenty-nine (76.3%) patients completed all 6 cycles of induction therapy with DA-EPOCH-R and 25 (65.8%) patients were able to undergo dose escalation of DA-EPOCH-R. Two (5.3%) patients had ixazomib dose reductions during induction and 10 (26.3%) patients had discontinuation of ixazomib during induction. Reasons for early discontinuation during induction included peripheral neuropathy, concomitant comorbidities, progressive disease, and death. Of the 21 (55.3%) patients who received maintenance therapy, 5 (23.8%) had ixazomib dose reductions, and 9 (42.9%) had discontinuation of ixazomib during maintenance. Reasons for early discontinuation during maintenance included peripheral neuropathy, patient preference, and progressive disease. Treatment-related adverse events (TRAEs) of interest occurring in b % 10 % of patients are noted in Table 2. The ORR after induction was 89% with an associated CR rate was 61%. One patient received autologous transplant as consolidation and did not pursue maintenance as a result. Estimated 24-months PFS and OS were 66.9% (95% CI, 50.7% to 88.4%) and 78.7% (95% CI, 65.10% to 95.52%), respectively. Of the 21 patients who received maintenance, sixteen had a CR while 5 had a PR. In those who achieved a PR and went on to receive maintenance, 1 patient converted to CR and 1 maintained a PR with ongoing response at last follow-up. Two patients progressed and 1 has not yet been re-evaluated for response. At a median follow up of 17.6 months (range: 14-19 months), 7 patients had PD. Six patients died, 3 from PD, 1 from respiratory failure, 1 from sepsis, and 1 from natural causes considered unrelated to study drug. CONCLUSION: In this older population with aggressive MYC-aberrant NHL, DA-EPOCH-R induction with adjunctive ixazomib followed by maintenance ixazomib appears to be safe and effective. It is notable that 31% of patients had ixazomib dose reduction or discontinuation during induction and only 55% of patients initiated maintenance, which may have compromised the efficacy of this approach. Exploratory analysis of clinical and histological variables is ongoing and will be presented at the meeting. Improving frontline outcomes for this subset of patients remains a critical unmet need. Disclosures Karmali: Karyopharm: Honoraria; AstraZeneca: Speakers Bureau; BeiGene: Speakers Bureau; Takeda: Research Funding; Gilead/Kite: Honoraria, Other, Research Funding, Speakers Bureau; BMS/Celgene/Juno: Honoraria, Other, Research Funding, Speakers Bureau. Hamadani:Takeda Pharmaceutical Company; Spectrum Pharmaceuticals; Astellas Pharma: Research Funding; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees; Sanofi Genzyme, AstraZeneca: Speakers Bureau; Janssen R&D; Incyte Corporation; ADC Therapeutics; Celgene Corporation; Pharmacyclics, Omeros, AbGenomics, Verastem, TeneoBio: Consultancy. Gordon:Zylem Biosciences: Patents & Royalties: Patents, No Royalties. Winter:Norvartis: Consultancy, Other: DSMB; Ariad/Takeda: Consultancy; CVS/Caremark: Consultancy; Delta Fly Pharma: Consultancy; Amgen: Consultancy; Epizyme: Other: DSMB; Merck: Membership on an entity's Board of Directors or advisory committees, Other: advisory board; Karyopharm: Membership on an entity's Board of Directors or advisory committees, Other: advisory board. Ma:TG Therapeutics: Research Funding; Novartis: Research Funding; Juno: Research Funding; Pharmacyclics, LLC, an AbbVie Company: Consultancy, Honoraria, Research Funding, Speakers Bureau; Kite: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Gilead: Consultancy, Honoraria; Genentech: Consultancy, Honoraria; Bioverativ: Consultancy, Honoraria; BeiGene: Honoraria, Research Funding, Speakers Bureau; AstraZeneca: Consultancy, Honoraria, Research Funding, Speakers Bureau; AbbVie: Consultancy, Honoraria, Research Funding. Fenske:Medical College of Wisconsin: Current Employment. Shah:Cell Vault: Research Funding; Miltenyi Biotec: Honoraria, Research Funding; Celgene: Consultancy, Honoraria; Incyte: Consultancy; TG Therapeutics: Consultancy; Verastim: Consultancy; Lily: Consultancy, Honoraria; Kite Pharma: Consultancy, Honoraria. Jagadeesh:Verastem: Membership on an entity's Board of Directors or advisory committees; Debiopharm Group: Research Funding; MEI Pharma: Research Funding; Regeneron: Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding. Klein:Takeda: Membership on an entity's Board of Directors or advisory committees. Petrich:AbbVie: Current equity holder in publicly-traded company; Daiichi-Sankyo: Current Employment. Evens:Epizyme: Consultancy, Honoraria, Research Funding; Merck: Consultancy, Honoraria, Research Funding; Pharmacyclics: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; MorphoSys: Consultancy, Honoraria; Research To Practice: Honoraria, Speakers Bureau; Abbvie: Consultancy, Honoraria; Mylteni: Consultancy, Honoraria; Seattle Genetics: Consultancy, Honoraria, Research Funding. Pro:Verastem Oncology: Research Funding. OffLabel Disclosure: Ixazomib is an orally bioavailable proteasome inhibitor that is FDA approved for multiple myeloma. It has also demonstrated preclinical activity in aggressive NHL, including double-hit (DH) lymphoma.

At present, multiple classes of agents with distinct mechanisms of action are available for the treatment of patients with multiple myeloma (MM), including alkylators, steroids, immunomodulatory agents (IMiDs), proteasome inhibitors (PIs), histone deacetylase inhibitors (DACIs), and monoclonal antibodies (mAbs). Over the last 5 years, several new agents, such as the third-generation IMiD pomalidomide, the second-generation PIs carfilzomib and ixazomib, the DACI panobinostat, and 2 mAbs, elotuzumab and daratumumab, have been approved, incorporated into clinical guidelines, and have transformed our approach to the treatment of patients. These agents may be part of doublet or triplet combinations, or incorporated into intensive strategies with autologous stem cell transplantation. In this review, I discuss the different treatment options available today for the treatment of MM in frontline and relapse settings.

The approval of several different classes of drugs in recent years has resulted in a dramatic expansion of treatment options for multiple myeloma patients, improving both survival and quality of life. Lenalidomide and bortezomib are now core components of treatment both at time of diagnosis and at relapse. Next-generation immunomodulatory drugs, like pomalidomide, and newer proteasome inhibitors like carfilzomib and ixazomib are available for use at relapse. Drugs with novel mechanisms of action such as the histone deacetylase inhibitor panobinostat and the monoclonal antibodies targeting SLAMF7 (elotuzumab) and CD38 (daratumumab) are significant steps forward. Recent clinical trials describing novel combinations of these drugs have demonstrated unprecedented improvements in efficacy while maintaining tolerability. All of these options provide not only a challenge for choice of therapy, but also the opportunity to aim for increasing depth of response. This chapter will describe an approach on how to sequence and incorporate these therapies, focusing on patients where high-dose melphalan and autologous stem cell transplant are deferred or not applicable.