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The relationship between regulatory T cells (Tregs) and acute graft-versus-host disease (aGVHD) in clinical allogeneic bone marrow transplantation (BMT) recipients is not well established. We conducted a prospective analysis of peripheral blood Tregs as determined by the frequency of CD4+CD25hiFOXP3+ lymphocytes in 215 BMT patients. Autologous BMT patients (N = 90) and allogeneic BMT patients without GVHD (N = 65) had similar Treg frequencies, whereas allogeneic patients with GVHD (N = 60) had Treg frequencies that were 40% less than those without GVHD. Treg frequencies decreased linearly with increasing grades of GVHD at onset, and correlated with eventual maximum grade of GVHD (P < .001). In addition, frequency of Tregs at onset of GVHD predicted the response to GVHD treatment (P = .003). Patients with Treg frequencies less than the median had higher nonrelapse mortality (NRM) than patients with Tregs greater than the median, but experienced equivalent relapse mortality, resulting in an inferior survival at 2 years (38% versus 63%, P = .03). Treg frequency may therefore have important prognostic value as a biomarker of aGVHD. [Copyright &y& Elsevier]

Danger-associated molecular patterns (DAMPs) released during conditioning have been shown to amplify experimental GVHD. CD24 fusion protein (CD24Fc; OncoImmune), a glycoprotein linked to human IgG 1 Fc, binds to Siglec-10 to negatively regulate host response to DAMPs. We have reported that infusion of CD24Fc prior to HCT significantly decreased GVHD-related mortality in murine models of HCT (Toubai, Blood 2015 & Toubai, JCI Insight 2017). We hypothesized that enhancing Siglec10-CD24 interactions by administration of CD24Fc would prevent acute GVHD. A randomized, prospective, multi-site, placebo controlled phase 2a clinical trial was initiated to investigate safety of three dose levels of CD24Fc (or blinded placebo) plus standard GVHD prophylaxis with tacrolimus and methotrexate (MTX) in matched unrelated donors. T cell replete PBSC or BMT was infused. Randomization (3:1 ratio of CD24Fc:Placebo) was in 3 cohorts of 8 pts: 240mg single dose on D -1, 480mg single dose on D -1, and a 480mg, 240mg, and 240mg multiple dose regimen on D -1, 14 and 28, respectively. The primary endpoint was safety and determination of a recommended dose. Pts were followed for secondary endpoints of aGVHD, relapse and survival at D180. The trial enrolled 24 pts (CD24Fc, n=18; Placebo, n=6) with minimum follow up on one year (Table1). All planned dosages were administered without reaching an MTD. There were no infusion-related toxicities or DLTs. In placebo treated pts, there was one DLT resulting in death from pneumonia. Between groups there were no overall differences in AEs, although CD24Fc was associated with fewer days of severe (≥ Grade III) mucositis. There was no infection-related mortality related to CD24Fc treatment. The CD24Fc pts achieved neutrophil and platelet engraftment at a median of D 13 (12-23) and D 13 (9-23), respectively. PK studies demonstrated sustained drug levels through D 100 in the multi-dosing cohort. The incidence of grade II-IV GVHD was 39% (18-62%) and III-IV GVHD was 6% (95% CI 0-20%) at D 180 among CD24Fc treated pts. Grade 3 involvement of the lower-GI tract was observed in 1/18 pts, while the remainder of acute GVHD involved the upper GI tract or skin. All pts receiving treatment for GVHD experienced response. At D 180, relapse occurred in 2/18 pts, and OS was 100%. The endpoint of grade 3-4 GVHD-free survival (AGFS) was 94% at D 180 in pts receiving treatment with CD24Fc versus 50% in pts receiving placebo (HR 0.1; 90% CI 0.0-0.7). AGFS in contemporaneous case matched controls (n=68; CIBMTR) receiving myeloablative 8/8 HLA matched unrelated donor HCT with tacrolimus + MTX was 68% (95% CI: 56-78). In this translational phase 2a trial administration of CD24Fc was safe and tolerable. Additional investigations are required determine efficacy for improving AGFS after HCT. This trial represents the first attempt to prevent GVHD by inhibiting host response to DAMPs. [ABSTRACT FROM AUTHOR]

INTRODUCTION The composite endpoint of GVHD-free, relapse-free survival (GRFS), defined as survival free from grade 3–4 acute GVHD (aGVHD), chronic GVHD (cGVHD) requiring systemic immunosuppressive therapy (IST), or relapse has emerged as an outcome to capture clinically meaningful events. In the present study, we validated GRFS as a useful surrogate endpoint by examining the relative importance of individual events and the GRFS composite itself on overall survival (OS) at 5-years after allogeneic HCT. METHODS We conducted an IRB-approved retrospective cohort study on 565 consecutive patients (age ≥18 years) undergoing first-time allogeneic HCT for hematologic malignancy (January 2007–March 2013). Data abstraction of GRFS events was performed through chart review of the EHR. To determine the impact of each event of the GRFS composite endpoint, we accounted for competing risks using Fine and Gray methods, and correlated each event with OS using Kaplan-Meier methods. Using statistical simulations, the relative consequences of successfully modulating individual or composite endpoints on OS were examined to further elucidate the role of GRFS in clinical trials research. RESULTS The median age of the cohort was 54 years (18–73 years), comprised predominantly of males (58%) and Caucasians (94%). The most common indication for transplant was AML (41%), followed by lymphoma (21%) and MDS/MPD (14%). Patients received HLA-matched related (47%), and matched unrelated (53%) donors, and mostly peripheral blood stem cells (90%) and myeloablative conditioning (68%). Relapse conferred the greatest risk for death (HR 7.89; 95% CI:5.83–10.69). Grade 3–4 aGVHD was associated with HR 6.16 (95%CI:4.42–8.56), while cGVHD requiring IST was associated with lower HR 1.69 (95%CI:1.16–2.46). Indeed, the GRFS composite correlated with less HR 4.81 (95% CI:3.61–6.41) compared with either relapse or grade 3–4 aGVHD events. To determine the impact of hypothetical improvements on individual events or combined events (composite) on OS, we next performed Monte Carlo simulations. Compared with individual events, modulating composite endpoints predicted the greatest change in 5-year OS (Figure 1). The greatest gain in OS was seen by proportionally reducing both grade 3–4 aGVHD and relapse (modified GRFS). Reducing chronic GVHD requiring IST proportionally with grade 3–4 aGVHD and relapse events (conventional GRFS) did not change 5-year OS. CONCLUSION These findings highlight the importance of influencing OS by targeting the major early adverse post-HCT events (i.e., grade 3–4 acute GVHD and relapse). Moreover, the simulations herein suggest that GRFS as currently defined may be less optimal for predicting OS than using early grade 3–4 aGVHD and relapse as composite endpoints. Importantly, further refinement of these endpoints will depend on the a priori defined study population as well as intervention. [ABSTRACT FROM AUTHOR]

Introduction Relapse remains a significant challenge towards improving survival after allogeneic hematopoietic transplantation (HCT) for Acute Myeloid Leukemia (AML) not in remission or possessing poor cytogenetic/molecular features. Insights from murine pre-clinical studies demonstrate a central role for CD8+ dendritic cells in cross-presentation of leukemia associated antigens (LAA) in mediating GVL without aggravating acute Graft-versus-Host Disease (aGVHD)(Toubai, Blood 2013). We posited that enhancing LAA cross-presentation with exogenous Type I Interferon (pegIFNα) would promote GVL response and reduce rates of relapse after HCT. Methods We initiated a prospective, phase I/II, clinical trial of pegIFNα administration after myeloablative conditioning for prevention of relapse in pts with detectable AML at time of HCT (resistant to induction) or with cytogenetic/molecular features conferring high relapse risk and poor survival. Pts received up to four doses of 90mcg or 180mcg pegIFNα SubQ on d -1 and d 14, 28, 42 after PBSC or BMT. aGVHD prophy was tacrolimus + MTX or MMF. The primary endpoint was to determine the incidence of relapse in pts receiving the phase II dosage of pegIFNα. We hypothesized that 30 pts assigned to the same dose would provide 80% power to detect a difference between a promising day 180 relapse rate of 40% versus a rate of 60%. Results A total of 30 pts received study treatment at a median age of 60 years (17-72). Conditioning was myeloablative FluBu (n=9), CloBu (n=20) or FluCyTBI (n=1). At time of HCT, AML was detected in 28 pts and 2 pts enrolled for poor cytogenetic/molecular risk, complex/monosomal karyotype (n=1) and FLT3-ITD+ (n=1). There was no DLT at 90mcg (n=3) and one DLT (graft failure) after escalation to 180mcg (n=27). pegIFNα was well tolerated with ≥3 doses administered to 87% of pts. ≥Grade 3 SAEs during treatment include acute kidney injury(n=1), engraftment failure(n=1), bone pain/weakness(n=1), hypotension(n=1) and hypoxemia (n=1). 29 pts (97%) experienced primary engraftment and bone marrow exam at d 30 revealed CR in 100% of pts. Thirteen pts (43%) experienced infection. Grade II-IV aGVHD and grade III-IV aGVHD occurred in 35% (20 – 56%) and 11% (4 – 30%) by day 180. The incidence of TRM was 11% (3-30%) at day 180 and 19% (8-41%) at 1-yr. The day 180 (and 1-yr) incidence of relapse was 39% (24 – 60%) in the overall cohort and 36% (20 – 58%) in 27 pts treated at the phase II dose. At a median follow up of 19 months, the 1-yr OS was 42% (27 – 65%). Conclusion These data provide initial evidence of clinical translation for pegIFNα when administered prophylactically in an AML cohort at high risk for relapse. Type I Interferon did not significantly alter toxicity or aGVHD risk and produced relatively low rates of relapse suggesting a robust GVL response. The role of type 1 IFN in reducing clinical relapse and its underlying biological mechanisms warrants additional study. [ABSTRACT FROM AUTHOR]

Treatment-related mucositis impacts over 75% of patients undergoing hematopoietic stem cell transplantation (HSCT). Signs and symptoms of mucositis typically manifest within 5-10 days post-conditioning and can persist for up to three weeks, thus leading to increased infection risk from mucosal barrier injury and challenges in maintaining nutrition status. Currently, there is no routinely utilized pharmacological or dietary agent for treatment or prophylaxis of mucositis. Zinc is an essential trace element that must be obtained via diet with functions such as but not limited to cell proliferation and differentiation, DNA synthesis, wound healing, and regulation of reactive oxygen species with the potential to exert these effects on mucositis. The purpose of this review is to understand available data on the relationship of oral zinc supplementation in prophylaxis and treatment of mucositis in hematological malignancies and thus implications for HSCT. A total of seven studies were selected for this review using PubMed, all of which follow a double-blinded, randomized controlled format performed on 30-140 patients. Inclusion criteria consists of adult human patients (>15 years old), a hematological malignancy diagnosis with subsequent chemotherapy and/or HSCT, administration of zinc prior to and/or during treatment, and publication date during or after 2009. Exclusion criteria consists of studies pertaining to pediatric patients, patients with non-hematological malignancies and studies with a publication date prior to 2009. Six out of seven studies concluded that zinc supplementation is efficacious in the prevention and treatment of mucositis. The incidence, duration and severity of mucositis symptoms can be significantly reduced with as little as twice daily dosing; five out of seven studies indicated a statistically significant reduction in mucositis grades 2-4 after 2-4 weeks of zinc supplementation. Based on these compelling findings, treatment avenues that exert an antioxidant or mucosal-protective effect, such as zinc supplementation, can serve to mitigate mucosal damage generated from conditioning regimens; the potential for zinc to reduce the high rates of mucositis seen in HSCT may be important to reduce infection risk and improve nutrition status. Zinc supplementation can be provided over-the-counter and is available in multiple administrative forms with good tolerance, rendering its use in clinical settings extremely practical. Based on these data, we believe prospective assessments of zinc status in HSCT are warranted and are now being evaluated at Michigan Medicine to identify patients at risk for severe mucositis. [ABSTRACT FROM AUTHOR]

BACKGROUND A recent U.S. Food and Drug Administration (FDA) safety communication (Aug 2018) warned prescribers of the risk of relapse in patients receiving azithromycin as prophylaxis for bronchiolitis obliterans syndrome (BOS) following hematopoietic cell transplant (HCT). However, the FDA warning was based upon a single multicenter trial, in which patients were randomized to receive azithromycin for 2 years, starting at the time of conditioning. We now examine relapse rates in a cohort of patients treated with azithromycin for management of moderate-severe CGVHD. PATIENT POPULATION A retrospective review of our HCT database (2010-2017) identified 239 patients (median age 55 years, range 4-72) with moderate-severe CGVHD following an allogeneic HCT for a primary hematologic malignancy. NIH consensus criteria (2015) were used for CGVHD grading. Patients were divided into 2 cohorts, a) those receiving an extended course of azithromycin (≥ 14 days) for CGVHD management (cohort 1, n=86) and b) those who did not (cohort 2, n=153). Patients in cohort 2 either did not receive any azithromycin (n=122) or had received an abbreviated (<14 day) course (n=31) of azithromycin post-HCT. For cohort 1, the median time to initiation of azithromycin therapy was 15 months post-HCT (range 3-68), with a 26 month median duration of azithromycin therapy (range 1-77). All patients in cohort 1 met NIH consensus criteria for BOS. Patients in cohort 2 did not exhibit BOS, but still met NIH criteria for moderate-severe CGVHD. Hematologic conditions included acute leukemia (n=139), MDS/MPD (n=44), malignant lymphomas (n=26), chronic leukemia (n=24), and multiple myeloma (n=6). Ninety-one patients exhibited moderate and 148 patients exhibited severe CGVHD. The two cohorts were balanced for CGVHD severity, with severe CGVHD noted in 69% and 63% of patients in cohorts 1 and 2 respectively. RESULTS Decreased rates of relapse and improved survival were noted for patients treated with azithromycin for CGVHD. At 2 years, the cumulative incidence of relapse was 2% (95% CI:1-9%) for patients in cohort 1 vs 16% (95% CI: 11-23%) in cohort 2, p=0.001. Overall survival (2-year OS) in cohort 1 was 93% (95%CI: 88-99%) vs 78% (95% CI:72-85%) for cohort 2, p=0.003. Overall, 7 of 86 (8.1%) CGVHD patients treated with an extended course of azithromycin (cohort 1) have relapsed, the median time to relapse 876 days (range 379-1303) post-HCT. In comparison, 28 of 153 (18.3%) in cohort 2 have relapsed, a median 371 days (range 98-1252) post-HCT. CONCLUSION The use of azithromycin for the management of moderate to severe CGVHD was not associated with an increased risk of relapse in patients undergoing HCT for a hematologic malignancy. Azithromycin therapy for patients with CGVHD should not be contra-indicated in this patient population. [ABSTRACT FROM AUTHOR]

Despite the ongoing advent of more effective immunomodulators and proteasome inhibitors, multiple myeloma (MM) remains incurable and no effective therapy is available for advanced aggressive disease. Although allogeneic (Allo) hematopoietic cell transplantation (HCT) has a curative potential, the outcomes remain poor because of high treatment-related mortality (TRM), mostly due to regimen-related toxicities and graft-versus-host disease (GVHD) in case of myeloablative conditionings, high relapse rate in case of reduced-intensity or nonmyeloablative regimens, and possibly other unknown MM-specific issues. In an attempt to improve TRM, without compromising conditioning intensity, we prospectively explored the feasibility and efficacy of a myeloablative but reduced-toxicity conditioning regimen, consisting of fludarabine and busulfan (FluBu4; fludarabine 40 mg/m 2 /day and busulfan 3.2 mg/kg/day i.v. × 4 days) in 22 patients with high-risk or advanced refractory MM. The majority (14 of 22, 64%) had prior autologous HCT. The median HCT-specific comorbidity index score was 3 (range, 0 to 6), with 46% having a Karnofsky performance score < 80%. Ten patients had unrelated donors, 3 of whom were 7/8 HLA–loci matched. GVHD prophylaxis was tacrolimus and methotrexate in 20 (91%). Most patients had active MM at transplantation, with a partial response in 12 of 22 (46%) and stable disease in 1 of 22 (4.5%). All 22 patients tolerated the FluBu4 conditioning well, without early toxic deaths or graft failure. Common regimen-related toxicities included mild to moderate mucositis (18 of 22, 82%) and mild transient liver function abnormality (9 of 22, 41%). There were no grade 4 toxicities but grade 3 mucositis occurred in 7 of 22 patients (32%). The cumulative incidence of severe, grades III and IV acute GVHD at day 180 was 23% (95% confidence interval [CI], 10% to 47%) and that of chronic GVHD was 68% (95% CI, 46% to 88%). The cumulative incidences of TRM at 100 days, 1 year, and 3 years were 9% (95% CI, 2% to 33%), 19% (95% CI, 7% to 44%), and 29% (95% CI, 13% to 55%), respectively. Two TRMs were due to idiopathic pneumonia syndrome and 1 was due to cirrhosis. They all had decreased pre-HCT corresponding organ function, with HCT-specific comorbidity index scores of > 3. With a median follow-up of 58.7 (range, 39 to 82) months, the cumulative incidences of relapse at 1 and 3 years were 37% (95% CI, 20% to 61%) and 50% (95% CI, 29% to 75%); those for 1-year and 3-year overall survival (OS) were 58% (95% CI, 40% to 83%) and 29% (95% CI, 15% to 57%), respectively, and those for the 1-year and 3-year progression-free survivals (PFS) were 40% (95% CI, 23% to 67%) and 15% (95% CI, 5% to 42%), respectively. In summary, the use of the myeloablative FluBu4 conditioning Allo-HCT for high-risk MM resulted in decreased TRM, compared with that of Allo-HCT using conventional myeloablative regimens; however, the relapse rate was high, including in those developing moderate-to-severe chronic GVHD. This suggested a less robust graft-versus-myeloma effect against high-risk MM, thus resulting in poor PFS and OS. Nonetheless, the FluBu4 regimen may be used as a lower-TRM platform to combine with other strategies, eg, addition of an MM-targeted agent and/or maintenance therapy with these agents, to decrease relapse or progression in patients with high-risk MM. [ABSTRACT FROM AUTHOR]

Clinical diagnosis of grade 1 acute graft-versus-host disease (GVHD) marks the beginning of a potentially progressive and fatal course of GVHD after hematopoietic stem cell transplantation (HSCT). However, interventional studies to treat early GVHD are lacking. We conducted a single-arm prospective phase II trial to test the hypothesis that treatment of newly diagnosed grade 1 acute GVHD with etanercept and topical corticosteroids would reduce progression to grade 2 to 4 within 28 days. Study patients (n = 34) had a median age of 51 years (range, 10 to 67 years) and had undergone unrelated (n = 22) or related (n = 12) donor HSCT. Study patients were treated with etanercept (.4 mg/kg, maximum 25 mg/dose) twice weekly for 4 to 8 weeks. Ten of 34 patients (29%) progressed to grade 2 to 4 acute GVHD within 28 days. The cumulative incidence of grade 2 to 4 and grade 3 to 4 acute GVHD at 1 year was 41% and 3%, respectively. Nonrelapse mortality was 19% and overall survival was 63% at 2 years. Among a contemporaneous control cohort of patients who were diagnosed with grade 1 acute GVHD and treated with topical corticosteroids but not etanercept during the study period, 12 of 28 patients (43%) progressed to grade 2 to 4 GVHD within 28 days, with a 1-year incidence of grade 2 to 4 GVHD and grade 3 to 4 GVHD of 61% (41% versus 61%, P = .08) and 18% (3% versus 18%, P = .05), respectively. Patients treated with etanercept also experienced less increase in GVHD plasma biomarkers suppression of tumorigenicity 2 (P = .06) and regenerating islet-derived 3-alpha (P = .01) 28 days after grade 1 acute GVHD diagnosis compared with contemporaneous control patients. This study was terminated early because of poor accrual. Future prospective studies are needed to identify patients with grade 1 acute GVHD at risk of swift progression to more severe GVHD and to establish consensus for the treatment of grade 1 acute GVHD. This trial is registered with ClinicalTrials.gov, number NCT00726375. [ABSTRACT FROM AUTHOR]

Engraftment syndrome (ES), characterized by fever, rash, pulmonary edema, weight gain, liver and renal dysfunction, and/or encephalopathy, occurs at the time of neutrophil recovery after hematopoietic cell transplantation (HCT). In this study, we evaluated the incidence, clinical features, risk factors, and outcomes of ES in children and adults undergoing first-time allogeneic HCT. Among 927 patients, 119 (13%) developed ES at a median of 10 days (interquartile range 9 to 12) after HCT. ES patients experienced significantly higher cumulative incidence of grade 2 to 4 acute GVHD at day 100 (75% versus 34%, P < .001) and higher nonrelapse mortality at 2 years (38% versus 19%, P < .001) compared with non-ES patients, resulting in lower overall survival at 2 years (38% versus 54%, P < .001). There was no significant difference in relapse at 2 years (26% versus 31%, P = .772). Suppression of tumorigenicity 2, interleukin 2 receptor alpha, and tumor necrosis factor receptor 1 plasma biomarker levels were significantly elevated in ES patients. Our results illustrate the clinical significance and prognostic impact of ES on allogeneic HCT outcomes. Despite early recognition of the syndrome and prompt institution of corticosteroid therapy, outcomes in ES patients were uniformly poor. This study suggests the need for a prospective approach of collecting clinical features combined with correlative laboratory analyses to better characterize ES. [ABSTRACT FROM AUTHOR]

Allogeneic HCT is the only established curative therapy for high risk hematologic malignancies. The major challenges are leukemia relapse and high grade GVHD. We have developed the CD24Fc fusion protein to selectively inhibit danger-associated molecular pattern (DAMP)-induced inflammation and discovered that it effectively prevents GVHD without affecting the desirable GVL effect in preclinical models. With the support of SBIR awards from the NCI, we have completed a phase II randomized, double blind, multi-center, dose escalation trial comprised of 3 dosing cohorts of 8 patients (3:1 CD24Fc vs. placebo), with a total enrollment of 24 subjects. Notably, clinical data from this trial demonstrate that CD24Fc reduces the incidence of severe GVHD, resulting in statistically significant increases of acute 180-day GVHD-free survival (aGFS). A Phase II expansion cohort to enroll an additional 20 subject is ongoing (NCT02663622). Here we propose a phase III clinical trial with 180 patients (1:1 CD24Fc vs placebo) to test the hypothesis that CD24Fc prophylaxis can significantly improve 180 day acute GVHD-free survival (aGFS) over placebo control. A Randomized, Double-blind, Placebo-controlled, Multi-Center, Phase III Study of CD24Fc for the Prevention of Acute GVHD Following Myeloablative Allogeneic HCT (CATHY) (NCT04095858). This study will compare CD24Fc or Placebo with standard GVHD prophylaxis of tacrolimus and methotrexate in the setting of myeloablative conditioning (MAC), matched unrelated donor (MUD) allogeneic HCT in patients with AML/ALL or MDS. Patients will be randomized 1:1 to receive CD24Fc or placebo at the dose levels of 480mg, 240mg and 240mg on Days -1, +14 and +28, respectively. The primary endpoint is the rate of 180 days grade III-IV acute GVHD-free survival (aGFS). Secondary endpoints are 1 yr DFS, 1 yr OS, and D180 Gr II-IV aGFS. Other exploratory evaluations will be 1 yr chronic GVHD, 1 yr relapse, NRM at 1 year, incidence and rate of infection at 100 days, and rate of Gr III and above mucositis at 28 days. The study will enroll 180 patients, or 90 per arm, with an estimated accrual period of 24 months. The study will include one interim analysis for efficacy. Z test statistics for comparing the two arms will be compared to the critical values and results be reviewed by the independent DSMB. [ABSTRACT FROM AUTHOR]

Introduction Genomic minimal residual disease (MRD) detected in complete remission using droplet digital PCR (ddPCR) is associated with inferior survival in AML patients when measured after induction chemotherapy and before and after allogeneic HSCT. However, the utility of high sensitivity genomic MRD detection in the context of allogeneic HSCT for patients with myelodysplastic syndrome (MDS) is unclear. Here we present data evaluating the association of genomic MRD with survival in HSCT recipients with MDS. Methods Peripheral blood mononuclear cells (PBMC) from 72 MDS patients sampled prior to HSCT were enriched for CD34+ cells and CD3+ cells using MACS columns. Genomic DNA extracted from CD34+ fractions underwent targeted next generation sequencing of 49 genes recurrently mutated in MDS. Variants were confirmed in the CD34+ fraction and germline polymorphisms excluded in the CD3+ fraction using Sanger resequencing. To date, mutations identified in 43 cases have been quantified with ddPCR in unfractionated PBMC genomic DNA prior to conditioning and at day 30 post-transplant with a sensitivity as low as 0.002%. Results A median of 2 mutations per case (range 1-4) was identified with NGS and subsequently measured with ddPCR. Prior to HSCT, 70% of cases had mutations with a variant allele frequency (VAF) ≥10% and had inferior OS compared to those with <10% VAF (HR 2.7 [1.2-5.7], p=0.04). At Day 30 after HSCT, 65% of patients still had detectable mutations in circulating PBMC (≥0.002% VAF) (MRDpos) and had inferior DFS (median 347d vs not reached; HR 3.6 [1.6-8.1], p<0.01) and OS (median 560d vs not reached; HR 4.0 [1.7-9.2], p<0.01) compared to patients with undetectable mutations (MRDneg). TP53 mutations remained detectable in all cases (8 of 8) along with most DNMT3A (4 of 7), RUNX1 (3 of 4), ASXL1 (3 of 5) and spliceosome gene mutations (5 of 8). The 1-year relapse rate was 35% in the MRDpos group and 5% in the MRDneg group (p=0.02). Non-relapse mortality in the MRDpos and MRDneg groups was 44% and 31%, respectively (p=0.99). In bivariate analyses, DFS and OS remained significantly inferior in MRDpos patients versus MRDneg patients when controlled for age, cytogenetics, IPSS-R at diagnosis or pre-HSCT, or presence of adverse gene mutations. In addition, MRDpos patients with mutations detected at <0.1% VAF (58% of MRDpos cases; median 0.009%, range 0.002-0.082% VAF) had equally inferior DFS and OS as MRDpos patients with mutations detected at ≥0.1% (42% of MRDpos cases; median 0.48%, range 0.12-16.1% VAF). Conclusion Ultrasensitive genomic MRD detection in PBMC of MDS patients 30 days after HSCT is feasible and is associated with increased relapse risk and inferior DFS and OS. The gene mutations of most MRDpos patients were detected at <0.1% VAF, suggesting ultrasensitive genomic MRD detection in peripheral blood identifies patients with very low level MRD at high risk for relapse and death post-HSCT. [ABSTRACT FROM AUTHOR]

Background Tisagenlecleucel, a chimeric antigen receptor T-cell therapy, has demonstrated efficacy and manageable safety in adult patients (pts) with relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL) in the global, multicenter, pivotal, phase 2, JULIET trial (NCT02445248). The primary endpoint, overall response rate (ORR), was met at the interim analysis (ORR: 59% [CR, 43%; PR, 16%]). Here, we report an updated analysis with a median 19 mo follow-up. Methods Adult pts ≥18 y with r/r DLBCL that had progressed after ≥2 lines of therapy including rituximab and an anthracycline and who were ineligible for or failed autologous stem cell transplant (ASCT) were enrolled. Tisagenlecleucel was manufactured from autologous T cells at 2 facilities (Morris Plains, NJ, USA [main cohort]. and Leipzig, Germany [cohort A]) and provided to pts at 27 treatment centers in 10 countries across the globe. Efficacy analyses include all pts with ≥3 mo of follow-up or earlier discontinuation. Safety analyses include all infused pts. Results In the JULIET study, 115 pts (99 in main cohort; 16 in cohort A) received a single dose of tisagenlecleucel infusion as of 21 May 2018. Prior to infusion, 90% of infused pts received bridging chemotherapy and 93% received lymphodepletion chemotherapy. Pts were a median 56 y (range, 22-76 y); 77% of pts had stage III/IV and 17% had double/triple-hit disease at the time of entry. Approximately half (51%) of pts had received ≥3 prior lines of chemotherapy (range, 1-6); 49% received prior ASCT. ORR was 54% (40% CR, 13% PR; 95% CI, 43%-64%) with a median follow-up of 19.3 mo post-infusion. Median duration of response (DOR) was not reached. The relapse-free probability was 66% (95% CI, 51%-78%) at 6 mo and 64% (95% CI, 48%-76%) at 12 or 18 mo. Consistent ORR was reported across prognostic subgroups (eg, prior ASCT; double/triple-hit lymphoma) and DOR was similar among age groups and disease status (Figure). Median OS was not reached for pts in CR and was 11.1 mo (95% CI, 6.6 mo-NE) for all infused pts. The probability of OS was 48% (95% CI, 38%-57%) at 12 mo and 43% (95% CI, 33%-53%) at 18 mo (max follow-up, 29 mo). No pts proceeded to allogeneic SCT or ASCT while in remission. During the first 8 wks post-infusion, grade 3/4 adverse events of special interest were cytopenias lasting >28 days (34%), cytokine release syndrome (CRS; 23%, by the Penn scale), infections (19%), febrile neutropenia (15%), neurologic events (11%; 1 case of grade 2 cerebral edema), and tumor lysis syndrome (2%). Tocilizumab was administered to 16% of pts with CRS, and no treatment-related death was reported. Conclusions This updated analysis with longer follow-up confirms earlier findings. Tisagenlecleucel produced a durable high ORR, consistent efficacy across all predefined subgroups, and had a manageable safety profile in pts with r/r DLBCL. [ABSTRACT FROM AUTHOR]