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Simple Summary: Ibrutinib is an established standard of care in the first-line treatment of chronic lymphocytic leukemia. Since ibrutinib is given continuously, data on long-term treatment, outcomes, and safety are essential to inform clinical decision making. Here, we describe characteristics and outcomes of patients who received long-term treatment with ibrutinib for ≥5 years in the phase 3 RESONATE-2 study. More than half (58%) of the patients randomly assigned to receive ibrutinib in the RESONATE-2 study continued to benefit from ibrutinib treatment for ≥5 years, regardless of baseline characteristics. Among patients who were on ibrutinib treatment for ≥5 years, complete response rates improved over time through the 5 years. The safety profile of ibrutinib treatment for ≥5 years was consistent with previous reports and no new safety signals were identified. For patients who experienced adverse events, dose modification was effective in resolving adverse events, thereby facilitating continued treatment. Primary results from the phase 3 RESONATE-2 study demonstrated superior efficacy and tolerability with ibrutinib versus chlorambucil in patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). Here, we describe characteristics and outcomes of patients who received ibrutinib treatment for ≥5 years in RESONATE-2. Patients aged ≥65 years with previously untreated CLL/SLL, without del(17p), were randomly assigned 1:1 to once-daily ibrutinib 420 mg until disease progression/unacceptable toxicity (n = 136) or chlorambucil 0.5–0.8 mg/kg for ≤12 cycles (n = 133). Baseline characteristics in ibrutinib-randomized patients (n = 136) were generally similar between patients on ibrutinib treatment for ≥5 years (n = 79) versus those on treatment for <5 years (n = 57). In patients on ibrutinib treatment for ≥5 years, complete response rates improved over time, reaching 42% by 5 years. Estimated 7-year progression-free survival and overall survival rates were 82% and 94%, respectively. Adverse events (AEs) led to dose reductions in 16/79 patients (20%); these AEs were resolved for 13/16 patients (81%). AEs led to dose holds (≥7 days) in 45/79 patients (57%); these AEs were resolved for 43/45 patients (96%). More than half (58%) of ibrutinib-randomized patients benefitted from ibrutinib treatment for ≥5 years regardless of baseline characteristics. Dose modification resolved AEs for most patients, thereby facilitating continued treatment. [ABSTRACT FROM AUTHOR]

At the time of study closure for relapsed/refractory patients (RESONATE), 38% of patients with 1-2 prior and 18% of patients with >=3 prior lines remained on ibrutinib treatment. Of 135 patients with relapsed/refractory disease, 68 patients had 1-2 prior lines, and 67 patients had >=3 prior lines of therapy. Ibrutinib, a first-in-class covalent inhibitor of Bruton's tyrosine kinase (BTK) approved in the United States and European Union for adult patients with CLL [[1]], has helped shift the treatment paradigm for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and other B-cell malignancies toward the use of novel targeted therapies. [Extracted from the article]

The author discusses a study published within the issue which reported the results of GAIA-CLL13, a four-group trial that was designed to answer several important questions related to time-limited therapy for young patients with chronic lymphocytic leukemia (CLL) who are fit. Topics include efficacy of the B-cell lymphoma 2 (BCL2) antagonist venetoclax in relapsed CLL and coexisting conditions, most intriguing data in the clinical trial, and one important aspect of the trial.

The therapeutic landscape for chronic lymphocytic leukemia has significantly evolved in recent years as our understanding of the biology of this disease has advanced. Chemoimmunotherapy has been the standard frontline treatment for patients of all age groups with chronic lymphocytic leukemia over the last decade. B-cell receptor signaling pathway plays a central role in the pathogenesis of chronic lymphocytic leukemia. The advent of novel small-molecule therapy for the treatment of chronic lymphocytic leukemia targeting the B-cell receptor signaling pathway has dramatically changed the therapeutic landscape with recent studies establishing ibrutinib, a Bruton's tyrosine kinase inhibitor, as the frontline treatment of choice regardless of patient's age, performance status or risk-category. Although these current advances along with the approval of other newer agents for the treatment of chronic lymphocytic leukemia is a significant step forward, newer challenges have emerged on how to best utilize these new treatment options. [ABSTRACT FROM AUTHOR]

The introduction of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib has dramatically changed the management of chronic lymphocytic leukemia (CLL). Although responses have been durable in the majority of patients, relapses do occur, especially in the high-risk patient population. Most relapses occur as the result of acquired mutations in BTK and PLCG2, which may facilitate success with alternative targeted therapies. As outcomes after ibrutinib relapse have been reported to be poor, specific strategies are needed for this patient population. Here, I discuss the diagnosis and management of ibrutinib-refractory CLL. The focus will be on common clinical scenarios that can be mistaken for relapse and how to accurately determine which patients are relapsing. Because there is no established standard of care, I discuss currently available options for standard therapy and existing clinical data. I also discuss new agents with the potential to be effective in patients refractory to ibrutinib. Finally, I discuss strategies for long-term disease control in this patient population. [ABSTRACT FROM AUTHOR]

The introduction of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib has dramatically changed the management of chronic lymphocytic leukemia (CLL). Although responses have been durable in the majority of patients, relapses do occur, especially in the high-risk patient population. Most relapses occur as the result of acquired mutations in BTK and PLCG2, which may facilitate success with alternative targeted therapies. As outcomes after ibrutinib relapse have been reported to be poor, specific strategies are needed for this patient population. Here, I discuss the diagnosis and management of ibrutinib-refractory CLL. The focus will be on common clinical scenarios that can be mistaken for relapse and how to accurately determine which patients are relapsing. Because there is no established standard of care, I discuss currently available options for standard therapy and existing clinical data. I also discuss new agents with the potential to be effective in patients refractory to ibrutinib. Finally, I discuss strategies for long-term disease control in this patient population. [ABSTRACT FROM AUTHOR]

The therapy of relapsed chronic lymphocytic leukemia (CLL) has changed dramatically in the past year with the regulatory approval of idelalisib and ibrutinib, with other therapeutic small molecules likely to become widely available in the next few years. Although durable remissions are being seen in many patients with these agents, it is becoming apparent that some patients with high genomic risk disease will relapse. Next-generation sequencing in patients as well as in vitro models is affording us the opportunity to understand the biology behind these relapses, which is the first step to designing rational therapies to prevent and treat targeted therapy-resistant CLL. These strategies are critical, as these relapses can be very difficult to manage, and a coordinated effort to put these patients on clinical trials will be required to efficiently determine the optimal therapies for these patients. In this review, we will describe mechanisms of resistance, both proven and hypothesized, for idelalisib, ibrutinib, and venetoclax, describe patterns of resistance that have been described with ibrutinib, and discuss potential strategies for management of disease resistant to these drugs as well as potential strategies to prevent resistance. [ABSTRACT FROM AUTHOR]

Ibrutinib has significantly improved the outcome of patients with relapsed chronic lymphocytic leukemia (CLL). Recent reports attribute ibrutinib resistance to acquired mutations in Bruton agammaglobulinemia tyrosine kinase (BTK), the target of ibrutinib, as well as the immediate downstream effector phospholipase C, γ2 (PLCG2). Although the C481S mutation found in BTK has been shown to disable ibrutinib's capacity to irreversibly bind this primary target, the detailed mechanisms of mutations in PLCG2 have yet to be established. Herein, we characterize the enhanced signaling competence, BTK independence, and surface immunoglobulin dependence of the PLCG2mutation at R665W, which has been documented in ibrutinib-resistant CLL. Our data demonstrate that this missense alteration elicits BTK-independent activation after B-cell receptor engagement, implying the formation of a novel BTK-bypass pathway. Consistent with previous results, PLCGR665EW confers hypermorphic induction of downstream signaling events. Our studies reveal that proximal kinases SYK and LYN are critical for the activation of m utant PLCG2 and that therapeutics targeting SYK and LYN can combat molecular resistance in cell line models and primary CLL cells from ibrutinib-resistant patients. Altogether, our results engender a molecular understanding of the identified aberration at PLCG2and explore its functional dependency on BTK, SYK, and LYN, suggesting alternative strategies to combat acquired ibrutinib resistance. [ABSTRACT FROM AUTHOR]

CD19 is ubiquitously expressed on chronic lymphocytic leukemia (CLL) cells and is therefore an attractive candidate for antibody targeting. XmAb5574 (aka MOR00208) is a novel humanized CD19 monoclonal antibody with an engineered Fc region to enhance Fcγ receptor binding affinity. Here we report results of a first in human phase 1 trial of XmAb5574 in patients with relapsed or refractory CLL. Twenty-seven patients were enrolled to 6 escalating dose levels, with expansion at the highest dose level of 12 mg/kg. Nine doses of XmAb5574 were infused over 8 weeks. No maximal tolerated dose was reached, and the drug was generally well tolerated, with infusion reactions of grades 1 and 2 being the most common toxicities. Grade 3 and 4 toxicities occurred in 5 patients and included neutropenia, thrombocytopenia, increased aspartate aminotransferase, febrile neutropenia, and tumor lysis syndrome. XmAb5574 showed preliminary efficacy, with 18 patients (66.7%) responding by physical examination criteria and laboratory studies, and 8 patients (29.6%) responding by computed tomography criteria. Pharmacokinetics showed a half-life of 14 days with clearance that was not dose-dependent. In conclusion, this phase 1 trial demonstrates safety and preliminary efficacy of a novel Fc-engineered CD19 monoclonal antibody XmAb5574 and justifies movement into the phase 2 setting. [ABSTRACT FROM AUTHOR]

The article presents a study on the resistance to ibrutinib which is an irreversible inhibitor of Bruton's tyrosine kinase (BTK). Topics include its effectiveness on the treatment of chronic lymphocytic leukemia (CLL), the use of whole-exome sequencing at baseline, and the mutation of cysteine-to-serine in BTK. It also features a table of the characteristics of patients with ibrutinib resistance.

The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib has outstanding activity in patients with chronic lymphocytic leukemia. Most patients experience lymphocytosis, representing lymphocyte egress from nodal compartments. This resolves within 8 months in the majority of patients, but a subgroup has lymphocytosis lasting >12 months. Here we report a detailed characterization of patients with persistent lymphocytosis during ibrutinib therapy. Signaling evaluation showed that while BTK is inhibited, downstream mediators of B-cell receptor (BCR) signaling are activated in persistent lymphocytes. These cells cannot be stimulated through the BCR and do not show evidence of target gene activation. Flow cytometry for κ and λ expression, IGHV sequencing, Zap-70 methylation, and targeted gene sequencing in these patients are identical at baseline and later time points, suggesting that persistent lymphocytes do not represent clonal evolution. In vitro treatment with targeted kinase inhibitors shows that they are not addicted to a single survival pathway. Finally, progression-free survival is not inferior for patients with prolonged lymphocytosis vs those with traditional responses. Thus, prolonged lymphocytosis is common following ibrutinib treatment, likely represents the persistence of a quiescent clone, and does not predict a subgroup of patients likely to relapse early. [ABSTRACT FROM AUTHOR]

Chronic lymphocytic leukemia (CLL) is characterized by constitutive activation of the B-cell receptor (BCR) signaling pathway, but variable responsiveness of the BCR to antigen ligation. Bruton’s tyrosine kinase (BTK) shows constitutive activity in CLL and is the target of irreversible inhibition by ibrutinib, an orally bioavailable kinase inhibitor that has shown outstanding activity in CLL. Early clinical results in CLL with other reversible and irreversible BTK inhibitors have been less promising, however, raising the question of whether BTK kinase activity is an important target of ibrutinib and also in CLL. To determine the role of BTK in CLL, we used patient samples and the Eμ-TCL1 (TCL1) transgenic mouse model of CLL, which results in spontaneous leukemia development. Inhibition of BTK in primary human CLL cells by small interfering RNA promotes apoptosis. Inhibition of BTK kinase activity through either targeted genetic inactivation or ibrutinib in the TCL1 mouse significantly delays the development of CLL, demonstrating that BTK is a critical kinase for CLL development and expansion and thus an important target of ibrutinib. Collectively, our data confirm the importance of kinase-functional BTK in CLL. [ABSTRACT FROM AUTHOR]

Targeted therapy with imatinib and other selective tyrosine kinase inhibitors has transformed the treatment of chronic my-eloid leukemia. Unlike chronic myeloid leukemia, chronic lymphocytic leukemia (CLL) lacks a common genetic aberration amenable to therapeutic targeting. How-ever, our understanding of normal B-cell versus CLL biology points to differences in properties of B-cell receptor (BCR) signaling that may be amenable to selec-tive therapeutic targeting. The applica-tion of mouse models has further expanded this understanding and provides information about targets in the BCR sig-naling pathway that may have other impor-tant functions in cell development or long-term health. In addition, overexpression or knockout of selected targets offers the potential to validate targets genetically using new mouse models of CLL. The initial success of BCR-targeted therapies has promoted much excitement in the field of CLL. At the present time, GS-1101, which reversibly inhibits PI3K8, and ibru-tinib (PCI-32765), an irreversible inhibitor of Bruton tyrosine kinase, have gener-ated the most promising early results in clinical trials including predominately re-fractory CLL where durable disease con-trol has been observed. This review pro-vides a summary of BCR signaling, tools for studying this pathway relevant to drug development in CLL, and early progress made with therapeutics targeting BCR-related kinases. [ABSTRACT FROM AUTHOR]

Interphase cytogenetics are commonly used to identify clonal abnormalities in chronic lymphocytic leukemia (CLL) patients but fail to identify recurrent translocations that ultimately can direct more focused molecular characterization. Given the importance of del(17p13.1) in CLL outcome, we performed an extensive review of 1213 patients undergoing metaphase cytogenetics at our institution and identified 16 (1·3%) with a recurrent unbalanced translocation between the p arms of chromosomes 17 and 18 that results in a dicentric chromosome with loss of much of 17p and 18p. The dic(17;18)(p11.2;p11.2) was associated with a complex (three or more unrelated cytogenetic abnormalities) karyotype in 12 patients (75%) at the time that the abnormality was first identified, and eventually associated with a complex karyotype in 94% of patients. IGHV mutational analysis was un-mutated in 88% of cases where evaluation was possible. Except for one patient who was diagnosed with CLL incidentally during a workup for metastatic tonsillar cancer, all patients identified with dic(17;18)(p11.2;p11.2) met criteria for disease treatment, with a median time from diagnosis to first treatment of 15 months. Our data demonstrate that dic(17;18)(p11.2;p11.2) is a novel recurrent cytogenetic abnormality in CLL associated with early age at diagnosis and accelerated disease progression. Future efforts to identify genes disrupted by this translocation are warranted and ongoing. [ABSTRACT FROM AUTHOR]

In this issue of Blood, Bercusson and colleagues report a mechanism underlying susceptibility to Aspergillus fumigatus infections in patients treated with the Bruton tyrosine kinase (Btk) inhibitor ibrutinib.1 This drug has been paradigm-shifting in a number of B-cell malignancies, which has led to widespread use in the diseases for which Food and Drug Administration approval currently exists, and clinical trials of the drug alone and in combination in these and many other malignancies. However, although well tolerated in the majority of patients, a few troublesome toxicities have become apparent as use of the drug has expanded. One such toxicity is a relatively high rate of A fumigatus infections. Although patients with hematologic malignancies are certainly at risk for opportunistic infections, A fumigatus infections at a higher rate than expected have been noted in multiple prospective studies, most notably a rate of 39% in patients on a trial of ibrutinib in primary central nervous system (CNS) lymphoma who were concurrently treated with corticosteroids.2 Although the incidence in other hematologic malignancies is likely quite a bit lower (2.5% in a large institutional cohort of 566 patients treated over 1225 person-years),3 this finding has been worrisome. A previous study by this group, exploring the risk of A fumigatus in patients treated with calcineurin inhibitors, demonstrated that Btk is required for the macrophage inflammatory response that clears A fumigatus from the airways,4 and a separate study showed that Btk null mice infected with A fumigatus developed pneumonia, similar to what is seen in macrophage-deplete models.2 However, the implications for these findings in patients where Btk is present but pharmacologically inactivated were previously unknown. [ABSTRACT FROM AUTHOR]

The author discusses the study by B. Apollonio and colleagues on the subset of chronic lymphocytic leukemia (CLL) patients which display phenotype by molecular anergy, where immunoglobulin litigation of B-cell receptor (BCR) do not lead to calcium flux or phosphotyrosine induction. The authors treated anergic phosphorylated extracellular signal-regulated kinase (pERK/2+) and nonanergic (pERK1/2-) CLL cells. The authors showed that markets inhibitors of anergy restore the sensitivity of BCR.

Acute myeloid leukemia (AML) is a highly aggressive hematologic cancer with poor survival across a broad range of molecular subtypes. Development of efficacious and well-tolerable therapies encompassing the range of mutations that can arise in AML remains an unmet need. The bromo- and extra-terminal domain (BET) family of proteins represents an attractive therapeutic target in AML due to their crucial roles in many cellular functions, regardless of any specific mutation. Many BET inhibitors (BETi) are currently in pre-clinical and early clinical development, but acquisition of resistance continues to remain an obstacle for the drug class. Novel methods to circumvent this development of resistance could be instrumental for the future use of BET inhibitors in AML, both as monotherapy and in combination. To date, many investigations into possible drug combinations of BETi with CDK inhibitors have focused on CDK9, which has a known physical and functional interaction with the BET protein BRD4. Therefore, we wished to investigate possible synergy and additive effects between inhibitors of these targets in AML. Here, we describe combination therapy with the multi-CDK inhibitor dinaciclib and the BETi PLX51107 in pre-clinical models of AML. Dinaciclib and PLX51107 demonstrate additive effects in AML cell lines, primary AML samples, and in vivo. Further, we demonstrate novel activity of dinaciclib through inhibition of the canonical/β-catenin dependent Wnt signaling pathway, a known resistance mechanism to BETi in AML. We show dinaciclib inhibits Wnt signaling at multiple levels, including downregulation of β-catenin, the Wnt co-receptor LRP6, as well as many Wnt pathway components and targets. Moreover, dinaciclib sensitivity remains unaffected in a setting of BET resistance, demonstrating similar inhibitory effects on Wnt signaling when compared to BET-sensitive cells. Ultimately, our results demonstrate rationale for combination CDKi and BETi in AML. In addition, our novel finding of Wnt signaling inhibition could have potential implications in other cancers where Wnt signaling is dysregulated and demonstrates one possible approach to circumvent development of BET resistance in AML. [ABSTRACT FROM AUTHOR]

The article discusses the follow up study on chronic lymphocytic leukemia (CLL)8 which uses fludarabine, cyclophosphamide, and rituximab (FCR) for initial therapy for CLL patients. Topics discussed include the paradigm of CLL therapy, the BCL2 inhibitor venetoclax trials, and the inappropriateness of FCR in the therapy.

Inhibitors of B cell receptor (BCR) signaling such as the Bruton's tyrosine kinase (BTK) inhibitors are effective therapeutics for chronic lymphocytic leukemia (CLL). The first-in-class covalent BTK inhibitor, ibrutinib, produces durable responses in most CLL patients; however, complete responses are only observed in a minority of patients. B cell lymphoma 2 (BCL2), an anti-apoptotic protein that contributes to CLL cell survival, has also been investigated as a therapeutic target. The BCL2 inhibitor venetoclax is effective in patients with CLL and can produce undetectable minimal residual disease, allowing discontinuation of therapy. In combination, ibrutinib and venetoclax have shown preclinical synergy and clinical efficacy. Nemtabrutinib is a next generation, reversible inhibitor of BTK that potently inhibits BCR signaling in treatment-naïve and ibrutinib-refractory CLL cells ex vivo. The clinical efficacy of combining BTK inhibitors with BCL2 inhibitors motivated us to evaluate the novel combination of nemtabrutinib and venetoclax. In vitro studies show that nemtabrutinib and venetoclax are not antagonistic to each other. In an adoptive transfer CLL mouse model, mice treated with nemtabrutinib and venetoclax had prolonged survival compared to mice treated with ibrutinib and venetoclax. Our preclinical studies further validate the combination of BTK inhibitors with venetoclax and justify further investigation of combining nemtabrutinib with venetoclax in CLL. [ABSTRACT FROM AUTHOR]

Background: Post-market analyses revealed unanticipated links between first-generation Bruton's tyrosine kinase inhibitor (BTKi) therapy, ibrutinib, and profound early hypertension. Yet, whether this is seen with novel selective second (next)-generation BTKi therapy, acalabrutinib, is unknown. Methods: Leveraging a large cohort of consecutive B cell cancer patients treated with acalabrutinib from 2014 to 2020, we assessed the incidence and ramifications of new or worsened hypertension [systolic blood pressure (SBP) ≥ 130 mmHg] after acalabrutinib initiation. Secondary endpoints were major cardiovascular events (MACE: arrhythmias, myocardial infarction, stroke, heart failure, cardiac death) and disease progression. Observed incident hypertension rates were compared to Framingham heart-predicted and ibrutinib-related rates. Multivariable regression and survival analysis were used to define factors associated with new/worsened hypertension and MACE, and the relationship between early SBP increase and MACE risk. Further, the effect of standard antihypertensive classes on the prevention of acalabrutinib-related hypertension was assessed. Results: Overall, from 280 acalabrutinib-treated patients, 48.9% developed new/worsened hypertension over a median of 41 months. The cumulative incidence of new hypertension by 1 year was 53.9%, including 1.7% with high-grade (≥ 3) hypertension. Applying the JNC 8 cutoff BP of ≥ 140/90 mmHg, the observed new hypertension rate was 20.5% at 1 year, > eightfold higher than the Framingham-predicted rate of 2.4% (RR 8.5, P < 0.001), yet 34.1% lower than ibrutinib (12.9 observed-to-expected ratio, P < 0.001). In multivariable regression, prior arrhythmias and Black ancestry were associated with new hypertension (HR 1.63, HR 4.35, P < 0.05). The degree of SBP rise within 1 year of treatment initiation predicted MACE risk (42% HR increase for each + 5 mmHg SBP rise, P < 0.001). No single antihypertensive class prevented worsened acalabrutinib-related hypertension. Conclusions: Collectively, these data suggest that hypertension may be a class effect of BTKi therapies and precedes major cardiotoxic events. [ABSTRACT FROM AUTHOR]

Objectives: Chronic lymphocytic leukaemia (CLL) is a lifelong cancer with subtle symptoms. Treatment is not curative and often involves repeated relapses and retreatments. Illness perceptions – cognitive and emotional representations of illness stimuli – were studied in CLL patients to: 1) identify illness perception 'profiles' prior to treatment; and 2) test whether profile membership predicts psychological responses 12 months later as treatment continued. Design: CLL patients (N = 259), randomized to one of four cancer treatment trials testing targeted therapy, were assessed before starting treatment and at 12 months. Methods: The Brief Illness Perception Questionnaire (BIPQ) assessed perceived consequences, timeline, personal/treatment control, identity, comprehension, concern, and emotions toward CLL. Psychological outcomes were depressive symptoms (PHQ‐9/BDI‐II), negative mood (POMS), and cancer stress (IES‐R). Latent profile analysis (LPA) determined number of profiles and differential BIPQ items for each profile. Multilevel models tested profiles as predictors of 12‐month psychological outcomes. Results: LPA selected the three‐profile model, with profiles revealing Low (n = 150; 57.9%), Moderate (n = 21; 8.1%), and High‐impact (n = 88; 34.0%) illness representations. Profiles were defined by differences in consequences, identity, concern, and emotions. Profile membership predicted all psychological outcomes (ps<.038). Low‐impact profile patients endorsed minimal psychological symptoms; High‐impact profile patients reported substantial symptoms. Conclusions: Results of the first CLL illness representation study provide directions for future clinical efforts. By identifying differences among patients' perceptions of CLL consequences, symptom burden, concerns, and emotional responses, an at‐risk patient group might receive tailored psychological treatment. Treatments may address negative perceptions, to reduce psychological risk associated with chronic cancer. [ABSTRACT FROM AUTHOR]

Aberrant regulation of endogenous survival pathways plays a major role in progression of chronic lymphocytic leukemia (CLL). Signaling via conjugation of surface receptors within the tumor environmental niche activates survival and proliferation pathways in CLL. Of these, the PI3K/AKT pathway appears to be pivotal to support CLL pathogenesis, and pharmacologic inhibitors targeting this axis have shown clinical activity. Here we investigate OSU-T315, a compound that disrupts the Phosphoinositide 3-kinase (PI3K)/AKT pathway in a novel manner. Dose-dependent, selective cytotoxicity by OSU-T315 is noted in both CLL-derived cell lines and primary CLL cells relative to normal lymphocytes. In contrast to the highly successful BTK and PI3K inhibitors that inhibit BCR signaling pathway at proximal kinases, OSU-T315 directly abrogates AKT activation by preventing translocation of AKT into lipid rafts without altering the activation of receptor-associated kinases. Through this mechanism, the agent triggers caspase-dependent apoptosis in CLL by suppressing BCR, CD49d, CD40 and TLR9-mediated AKT activation in an ILK-independent manner. In vivo, OSU-T315 attains pharmacologically active drug levels and significantly prolongs survival in the TCL1 mouse model. Together, our findings indicate a novel mechanism of action of OSU-T315 with potential therapeutic application in CLL. [ABSTRACT FROM AUTHOR]

Patients with relapsed/refractory chronic lymphocytic leukemia (R/R CLL) whose treatment failed with a Bruton's tyrosine kinase inhibitor have poor outcomes. We investigated tafasitamab plus idelalisib (cohort A) or venetoclax (cohort B) in this patient population in a phase II study (NCT02639910). In total, 24 patients were enrolled (cohort A: n = 11, median time on study, 7.4 months; cohort B: n = 13, median time on study, 15.6 months). The most common treatment-emergent adverse event (TEAE) in cohort A was anemia (63.6%) and in cohort B was infusion-related reaction (53.8%). The most common severe TEAE was neutropenia (cohort A: 45.5%; cohort B: 46.2%). The best overall response rate was 90.9% (cohort A) and 76.9% (cohort B). Undetectable minimal residual disease in peripheral blood was achieved in 2/8 patients (cohort A) and 6/7 patients (cohort B). Overall, these results suggest that anti-CD19 antibody-based combinations may be important in the treatment of patients with CLL. [ABSTRACT FROM AUTHOR]

There is currently a critical need to determine the efficacy of SARS-CoV-2 vaccination for immunocompromised patients. In this study, we determined the neutralizing antibody response in 160 cancer patients diagnosed with chronic lymphocytic leukemia (CLL), lung cancer, breast cancer, and various non-Hodgkin's lymphomas (NHL), after they received two doses of mRNA vaccines. Serum from 46 mRNA vaccinated health care workers (HCWs) served as healthy controls. We discovered that (1) cancer patients exhibited reduced neutralizing antibody titer (NT50) compared to HCWs; (2) CLL and NHL patients exhibited the lowest NT50 levels, with 50-60% of them below the detection limit; (3) mean NT50 levels in patients with CLL and NHL was ~2.6 fold lower than those with solid tumors; and (4) cancer patients who received anti-B cell therapy exhibited significantly reduced NT50 levels. Our results demonstrate an urgent need for novel immunization strategies for cancer patients against SARS-CoV-2, particularly those with hematological cancers and those on anti-B cell therapies. [ABSTRACT FROM AUTHOR]

Background: Covalent Bruton's tyrosine kinase (BTK) inhibitors are efficacious in multiple B-cell malignancies, but patients discontinue these agents due to resistance and intolerance. We evaluated the safety and efficacy of pirtobrutinib (working name; formerly known as LOXO-305), a highly selective, reversible BTK inhibitor, in these patients.Methods: Patients with previously treated B-cell malignancies were enrolled in a first-in-human, multicentre, open-label, phase 1/2 trial of the BTK inhibitor pirtobrutinib. The primary endpoint was the maximum tolerated dose (phase 1) and overall response rate (ORR; phase 2). This trial is registered with ClinicalTrials.gov, NCT03740529.Findings: 323 patients were treated with pirtobrutinib across seven dose levels (25 mg, 50 mg, 100 mg, 150 mg, 200 mg, 250 mg, and 300 mg once per day) with linear dose-proportional exposures. No dose-limiting toxicities were observed and the maximum tolerated dose was not reached. The recommended phase 2 dose was 200 mg daily. Adverse events in at least 10% of 323 patients were fatigue (65 [20%]), diarrhoea (55 [17%]), and contusion (42 [13%]). The most common adverse event of grade 3 or higher was neutropenia (32 [10%]). There was no correlation between pirtobrutinib exposure and the frequency of grade 3 treatment-related adverse events. Grade 3 atrial fibrillation or flutter was not observed, and grade 3 haemorrhage was observed in one patient in the setting of mechanical trauma. Five (1%) patients discontinued treatment due to a treatment-related adverse event. In 121 efficacy evaluable patients with chronic lymphocytic leukaemia (CLL) or small lymphocytic lymphoma (SLL) treated with a previous covalent BTK inhibitor (median previous lines of treatment 4), the ORR with pirtobrutinib was 62% (95% CI 53-71). The ORR was similar in CLL patients with previous covalent BTK inhibitor resistance (53 [67%] of 79), covalent BTK inhibitor intolerance (22 [52%] of 42), BTK C481-mutant (17 [71%] of 24) and BTK wild-type (43 [66%] of 65) disease. In 52 efficacy evaluable patients with mantle cell lymphoma (MCL) previously treated with covalent BTK inhibitors, the ORR was 52% (95% CI 38-66). Of 117 patients with CLL, SLL, or MCL who responded, all but eight remain progression-free to date.Interpretation: Pirtobrutinib was safe and active in multiple B-cell malignancies, including patients previously treated with covalent BTK inhibitors. Pirtobrutinib might address a growing unmet need for alternative therapies for these patients.Funding: Loxo Oncology. [ABSTRACT FROM AUTHOR]

Among 13 patients that met IWCLL treatment criteria but did not start alternative therapy, 2 patients were deemed to be unable to tolerate further therapy by treating physician, 5 patients elected not to start alternative therapy, 2 patients died, 1 had a secondary malignancy, and 3 patients were lost to follow up. Disease progression in treatment naïve patients during treatment with ibrutinib is infrequent, but for relapsed patients with high-risk characteristics, progression occurs more frequently, and has been associated with poor survival [[1]]. Initial reports of patients who discontinued ibrutinib therapy for non-relapse reasons demonstrated a median survival of 8 days, however these results were heavily influenced by patients who discontinued therapy secondary to an infectious complication [[4]]. A retrospective review of 56 CLL patients that developed atrial fibrillation while on ibrutinib showed that atrial fibrillation was persistent in 35 of 56 (62%) cases despite treatment and prompted permanent discontinuation of ibrutinib in 26 of 56 (46%) patients [[12]]. [Extracted from the article]

B-cell receptor (BCR) antagonists such as the BTK inhibitor ibrutinib have proven to effectively target chronic lymphocytic leukemia (CLL) tumor cells, leading to impressive response rates in these patients. However patients do still relapse on ibrutinib, and the progressive disease is often quite aggressive requiring immediate treatment. Several strategies are being pursued to treat patients who relapse on ibrutinib therapy. As the most common form of relapse is the development of a mutant form of BTK which limits ibrutinib binding, agents which lead to degradation of the BTK protein are a promising strategy. Our study explores the efficacy of the Hsp90 inhibitor, SNX-5422, in CLL. The SNX Hsp90 inhibitor was effective in primary CLL cells, as well as B-cell lines expressing either BTK wild type or C481 mutant BTK, which has been identified as the primary resistance mechanism to ibrutinib in CLL patients. Furthermore the combination of SNX-5422 and ibrutinib provided a remarkable in vivo survival benefit in the Eμ-TCL1 mouse model of CLL compared to the vehicle or single agent groups (51 day median survival in the vehicle and ibrutinib groups versus 100 day median survival in the combination). We report here preclinical data suggesting that the Hsp90 inhibitor SNX-5422, which has been pursued in clinical trials in both solid tumor and hematological malignancies, is a potential therapy for ibrutinib resistant CLL. [ABSTRACT FROM AUTHOR]

Purpose: This study assessed whether empirically supported risk factors can identify future depression and anxiety symptoms in a specific cancer type, chronic lymphocytic leukemia (CLL).Methods: Patients enrolled in a CLL treatment clinical trial (N = 106) participated at baseline following informed consent and prior to treatment initiation. Risk factors with empirical support (personal or family psychiatric history, recurrent, advanced or progressive disease, low socioeconomic status, gender, medical comorbidities, and single marital status) and additional risk factors (cancer-specific stress, social contacts, negative life events, absolute lymphocyte counts, treatment group, and fatigue) were measured at baseline to predict depression and anxiety symptoms at 12 months.Results: Data show 14% (n = 15) and 12% (n = 13) of patients experienced moderate-severe depression and anxiety symptoms, respectively. Multiple linear regression analyses found medical comorbidities predicted 12-month anxiety symptoms (p < 0.05). Also, negative life events predicted depression and anxiety symptoms and fatigue predicted depression symptoms (p < 0.05).Conclusion: Empirically supported risk factors associated with depression and anxiety symptoms are limited in predicting future depression and anxiety symptoms beyond initial screening in patients with CLL. In addition to levels of depression and anxiety symptoms at baseline, negative life events, higher levels of fatigue, and greater medical comorbidities were associated with future depression or anxiety symptoms in patients with CLL. [ABSTRACT FROM AUTHOR]

• Autologous stem cell transplant (ASCT) induces global transcriptional T cell changes and altered molecular levels of markers of T cell subtypes, T cell activation, and exhaustion in patients with multiple myeloma. • High LAG3 transcript expression in T cells detectable as early as 3 months post-transplant is associated with inferior clinical outcomes in patients with myeloma. • ASCT affected soluble levels of molecules with immunomodulatory function by increasing plasma HVEM and TIM3. • ASCT promotes an exhausted immunophenotype in CD4+ cells and a senescent/anergic immunophenotype in CD8+ subsets. • Future work targeting immune defects in multiple myeloma is warranted to augment or restore T cell responses using the next generation of immune checkpoint inhibitors. Autologous stem cell transplant (ASCT) is the standard of care for patients with multiple myeloma (MM). The clinical significance of peripheral blood T lymphocyte (PBTL) immunologic changes associated with ASCT is poorly understood. Here we evaluated T cell transcriptional messenger RNA profiles and immunophenotypes to correlate immunologic senescence, exhaustion, and anergy with clinical endpoints in a cohort of patients with MM undergoing ASCT. ASCT induced global transcriptional T cell changes and altered molecular levels of markers of T cell subtypes, T cell activation, and exhaustion. These included reduced CD4/CD8 ratio, skewing toward the Th1 subset, reduced expression of costimulatory receptors CD27 and CD28, heightened T cell activation, and increased expression of immune modulatory molecules LAG3 and PD1. Multicolor flow cytometry experiments confirmed altered circulating CD4 and CD8 subsets and skewing toward differentiated effector cells. Moreover, ASCT promoted an exhausted immunophenotype in CD3+CD4+ subsets and a senescent immunophenotype in CD3+CD8+ subsets. Subset-specific altered expression was also seen for surface molecules with immunomodulatory function. ASCT affected soluble levels of molecules with immunomodulatory function by increasing plasma HVEM and TIM3. High molecular LAG3 level was associated with inferior event-free survival post-ASCT (hazard ratio = 5.44; confidence interval, 1.92 to 15.46; P =.001; adjusted P [controlling for false discovery rate] =.038). Using a comprehensive evaluation of PBTLs on a molecular and phenotypic level, we have identified that ASCT induces global T cell alterations with CD4 and CD8 subset-specific changes. Moreover, LAG3 emerged as an early biomarker of adverse events post-ASCT. These findings will support the development of treatment strategies targeting immune defects in MM to augment or restore T cell responses. [ABSTRACT FROM AUTHOR]

GLO:1XW/01nov19:bjh16209-fig-0001.jpg PHOTO (COLOR): Cumulative incidence of venous and arterial thrombosis in patients with a haematological malignancy during treatment with ibrutinib. gl Platelet counts at the time of the central nervous system haemorrhage were 34 × 10 SP 9 sp /l and 42 × 10 SP 9 sp /l. One patient developed a recurrent central line-associated thrombosis while on ibrutinib and AC. However, many patients in our study received concomitant antiplatelet agents or AC (39-6% and 8-3%, respectively), which may have reduced the risk of thrombosis even though the median overlap was short. The majority who developed a thrombosis while on ibrutinib were started on anti-platelet agents and/or AC, but many experienced bleeding events and recurrent thrombosis was rare. [Extracted from the article]

Background: Leventhal's Self-regulatory Model proposes that somatic characteristics of a health threat (e.g., symptom severity), and prior experience with the threat (e.g., unsuccessful treatment), are determinants of illness perceptions. Chronic lymphocytic leukemia (CLL) is appropriate for test of these postulates, having three phases differing in symptom severity and prior treatment experiences: indolent disease requiring no treatment (active surveillance; AS), symptomatic disease requiring a first treatment (FT), and highly symptomatic disease in those who have relapsed and/or failed to respond to prior treatments (relapsed/refractory; RR).Purpose: To test symptom severity and prior treatment experiences as determinants of illness perceptions, illness perceptions were characterized and contrasted between CLL groups.Methods: Three hundred and thirty CLL patients (AS, n = 100; FT, n = 78; RR, n = 152) provided illness perception data on one occasion during a surveillance visit (AS) or prior to beginning treatment (FT, RR).Results: Analysis of variance with planned comparisons revealed that consequences, identity, and concern were least favorable among RR patients, followed by FT, then AS (ps < .01). AS patients endorsed the lowest levels of coherence (ps < .01), and the most chronic illness timeline (ps < .01). FT patients endorsed the highest levels of personal and treatment control (ps < .01).Conclusions: Data provide preliminary empirical support for Self-regulatory Model postulates that symptom severity and prior disease experiences influence illness perceptions. Unique knowledge needs for AS patients and elevated psychological/physical symptoms for later-stage CLL patients may warrant clinical attention. [ABSTRACT FROM AUTHOR]

The treatment of acute myelogenous leukemia (AML) relies heavily on cytarabine (Ara-C) containing chemotherapy. (b) Immunoblot analysis of Chk1, Rad51, and GAPDH (loading control) in AML blasts cells after exposure to a 0.25 µM onalespib for 24 or 36 h. (c) OCI-AML3 cells were left untreated (control) or exposed to 0.25 µM onalespib for 24 h before undergoing DNA damage with 2 Gy IR. However, cells exposed to the combination of onalespib and Ara-C strongly induce S-phase arrest which may explain the mechanism by which onalespib sensitizes OCI-AML3 cells to Ara-C. [Extracted from the article]

Aim: The objective of this study was to determine whether survival and post-arrest procedural utilization following in-hospital cardiac arrest (IHCA) differ in patients with and without comorbid cancer.Methods: We retrospectively reviewed all adult (age ≥18 years old) hospital admissions complicated by IHCA from 2003 to 2014 using the National Inpatient Sample (NIS) dataset. Utilizing propensity score matching using age, gender, race, insurance, all hospital level variables, HCUP mortality score, diabetes, hypertension and cardiopulmonary resuscitation use, rates of survival to hospital discharge and post-arrest procedural utilization were compared.Results: From 2003 to 2014, there were a total of 1,893,768 hospitalizations complicated by IHCA, of which 112,926 occurred in patients with history of cancer. In a propensity matched cohort from 2012 to 2014, those with cancer were less likely to survive the hospitalization (31% vs. 46%, p < 0.0001). Following an IHCA, rates of procedural utilization in patients with cancer were significantly less when compared to those without a concurrent malignancy: coronary angiography (4.0% vs. 13.0%), percutaneous coronary intervention (2.2% and 8.0%), targeted temperature management (0.8% vs. 6.0%); p < 0.0001 for all comparisons. This patient population was less likely to have acute coronary syndrome (12.6% vs. 27.0%) or congestive heart failure (24.5% vs. 38.2%); p < 0.0001 for both comparisons. Survival improved in both groups over the study period (p < 0.0001).Conclusions: Patients with a history of cancer who sustain IHCA are less likely to receive post-arrest procedures and survive to hospital discharge. Given the expected rise in the rates of cancer survivorship, these findings highlight the need for broader application of potentially life-saving interventions to lower risk cancer patients who have sustained a cardiac arrest. [ABSTRACT FROM AUTHOR]

The article focuses on the use of PD-1 (PDCD1) inhibitors for the treatment of Richter syndrome (RS). Topics include the programmed death receptor-1 blocking antibodies, and nivolumab, have shown efficacy in prospective clinical trials with a small number of RS patients; mentions ten patients with biopsy-proven RS with diffuse large B-cell lymphoma histology; and the treatment of RS demonstrates by using PD-1 inhibitors demonstrates poor efficacy with a short time to treatment failure.

Targeted therapies including the engineered afucosylated anti-CD20 monoclonal antibody obinutuzumab, Bruton's tyrosine kinase inhibitor ibrutinib, and B-cell lymphoma protein 2 inhibitor venetoclax have demonstrated significant clinical activity in chronic lymphocytic leukemia (CLL) and, based on their complementary mechanisms, are ideal for combination. However, combining venetoclax with other active agents raises safety concerns, as it may increase the risk for tumor lysis syndrome. To minimize this risk, we designed and implemented a fixed-duration regimen using sequentially administered obinutuzumab followed by ibrutinib (cycle 2) and venetoclax (cycle 3), for a total of fourteen 28-day cycles. This phase 1b study included 12 patients with relapsed or refractory CLL. We tested 3 dose levels of venetoclax and identified the doses of all 3 agents approved by the US Food and Drug Administration for use in the combination. Adverse events were consistent with known toxicities of the individual agents, with hematologic adverse events being most frequent. No clinically significant tumor lysis syndrome occurred. The overall response rate was 92% (95% confidence interval, 62%-100%), with 42% (5/12) achieving a complete remission or complete remission with incomplete marrow recovery. There were 6 patients with no detectable CLL in both the blood and bone marrow at the end of treatment. We found this regimen to be safe and tolerable in CLL, and capable of inducing deep responses, justifying future study in our ongoing phase 2 cohorts of relapsed or refractory and treatment-naive patients, as well as larger phase 3 trials currently in planning. This trial was registered at www.clinicaltrials.gov as #NCT02427451. [ABSTRACT FROM AUTHOR]

The clinical success of ibrutinib validates Bruton tyrosine kinase (BTK) inhibition as an effective strategy for treating hematologic malignancies, including chronic lymphocytic leukemia (CLL). Despite ibrutinib's ability to produce durable remissions in patients, acquired resistance can develop, mostly commonly by mutation of C481 of BTK in the ibrutinib binding site. Here, we characterize a novel BTK inhibitor, GDC-0853, to evaluate its preclinical efficacy in ibrutinib-naive and ibrutinib-resistant CLL. GDC-0853 is unique among reported BTK inhibitors in that it does not rely upon covalent reaction with C481 to stabilize its occupancy within BTK's adenosine triphosphate binding site. As with ibrutinib, GDC-0853 potently reduces B-cell receptor signaling, viability, NF-kB-dependent transcription, activation, and migration in treatment naïve CLL cells. We found that GDC-0853 also inhibits the most commonly reported ibrutinib-resistant BTK mutant (C481S) both in a biochemical enzyme activity assay and in a stably transfected 293T cell line and maintains cytotoxicity against patient CLL cells harboring C481S BTK mutations. Additionally, GDC-0853 does not inhibit endothelial growth factor receptor or ITK, 2 alternative targets of ibrutinib that are likely responsible for some adverse events and may reduce the efficacy of ibrutinib-antibody combinations, respectively. Our results using GDC-0853 indicate that noncovalent, selective BTK inhibition may be effective in CLL either as monotherapy or in combination with therapeutic antibodies, especially among the emerging population of patients with acquired resistance to ibrutinib therapy. [ABSTRACT FROM AUTHOR]

Abstract: Evaluating population‐based data of hematologic malignancies (HMs) in older adults provides prognostic information for this growing demographic. Incidence rates and one‐ and five‐year relative survival rates were examined for specific HMs among adults ages ≥75 years using data from the Surveillance, Epidemiology and End Results (SEER) Program. Hematologic malignancy cases (Hodgkin lymphoma (HL), non‐Hodgkin lymphoma (NHL), multiple myeloma (MM), acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute myeloid leukemia (AML), and chronic myeloid leukemia (CML)) were reported to one of 18 SEER registries. Recent average annual (2010–2014) incidence rates and incidence trends from 1973 to 2014 were examined for cases ages ≥75 years. One‐ and five‐year relative cancer survival rates were examined for adults ages ≥75 years diagnosed 2007–2013, with follow‐up into 2014. From 1973 to 2014, incidence rates increased for NHL, MM, and AML, decreased for HL, and remained relatively stable for ALL, CLL, and CML among adults ages ≥75 years. The highest one‐ and five‐year relative survival rates were observed among adults with CLL ages 75–84 years (1 year: 91.8% (95% CI = 91.8–90.8)) and 5 years: 76.5% (95% CI = 74.2–78.6)). The lowest one‐ and five‐year survival rates were observed among adults with AML ages 75–84 (1 year: 18.2% (95% CI = 74.2–78.6) and 5 years: 2.7% (95% CI = 2.0–3.6)). Survival for older adults ages ≥75 years with HMs is poor, particularly for acute leukemia. Understanding the heterogeneity in HM outcomes among older patients may help clinicians better address the hematological cancer burden and mortality in the aging population. [ABSTRACT FROM AUTHOR]

The article discusses research which examined the role and regulation of microRNAs targeting Bruton tyrosine kinase (BTK) in the survival of acute myelogenous leukemia (AML) cells. The study showed that BTK is a relevant therapeutic target in AML cells and the key signature of microRNA that regulated BTK. The flow cytometry analysis confirmed that BTK protein expression was downregulated by each microRNA. Also, ibrutinib exposure inhibited the kinase activity of BTK in OCI-AML3 cells.

Background: Therapy targeting Bruton's tyrosine kinase (BTK) with ibrutinib has transformed the treatment of chronic lymphocytic leukaemia. However, patients who are refractory to or relapse after ibrutinib therapy have poor outcomes. Venetoclax is a selective, orally bioavailable inhibitor of BCL-2 active in previously treated patients with relapsed or refractory chronic lymphocytic leukaemia. In this study, we assessed the activity and safety of venetoclax in patients with chronic lymphocytic leukaemia who are refractory to or relapse during or after ibrutinib therapy.Methods: In this interim analysis of a multicentre, open-label, non-randomised, phase 2 trial, we enrolled patients aged 18 years or older with a documented diagnosis of chronic lymphocytic leukaemia according to the 2008 International Workshop on Chronic Lymphocytic Leukemia (IWCLL) criteria and an Eastern Cooperative Oncology Group performance score of 2 or lower. All patients had relapsed or refractory disease after previous treatment with a BCR signalling pathway inhibitor. All patients were screened for Richter's transformation and cases confirmed by biopsy were excluded. Eligible patients received oral venetoclax, starting at 20 mg per day with stepwise dose ramp-up over 5 weeks to 400 mg per day. Patients with rapidly progressing disease received an accelerated dosing schedule (to 400 mg per day by week 3). The primary endpoint was overall response, defined as the proportion of patients with an overall response per investigator's assessment according to IWCLL criteria. All patients who received at least one dose of venetoclax were included in the activity and safety analyses. This study is ongoing; data for this interim analysis were collected per regulatory agencies' request as of June 30, 2017. This trial is registered with ClinicalTrials.gov, number NCT02141282.Findings: Between September, 2014, and November, 2016, 127 previously treated patients with relapsed or refractory chronic lymphocytic leukaemia were enrolled from 15 sites across the USA. 91 patients had received ibrutinib as the last BCR inhibitor therapy before enrolment, 43 of whom were enrolled in the main cohort and 48 in the expansion cohort recruited later after a protocol amendment. At the time of analysis, the median follow-up was 14 months (IQR 8-18) for all 91 patients, 19 months (9-27) for the main cohort, and 12 months (8-15) for the expansion cohort. 59 (65%, 95% CI 53-74) of 91 patients had an overall response, including 30 (70%, 54-83) of 43 patients in the main cohort and 29 (60%, 43-72) of 48 patients in the expansion cohort. The most common treatment-emergent grade 3 or 4 adverse events were neutropenia (46 [51%] of 91 patients), thrombocytopenia (26 [29%]), anaemia (26 [29%]), decreased white blood cell count (17 [19%]), and decreased lymphocyte count (14 [15%]). 17 (19%) of 91 patients died, including seven because of disease progression. No treatment-related deaths occurred.Interpretation: The results of this interim analysis show that venetoclax has durable clinical activity and favourable tolerability in patients with relapsed or refractory chronic lymphocytic leukaemia whose disease progressed during or after discontinutation of ibrutinib therapy. The durability of response to venetoclax will be assessed in the final analysis in 2019.Funding: AbbVie, Genentech. [ABSTRACT FROM AUTHOR]

Background: Ibrutinib has been shown to have immunomodulatory effects by inhibiting Bruton's tyrosine kinase (BTK) and IL-2-inducible T cell kinase (ITK). The relative importance of inhibiting these 2 kinases has not been examined despite its relevance to immune-based therapies.Methods: Peripheral blood mononuclear cells from chronic lymphocytic leukemia (CLL) patients on clinical trials of ibrutinib (BTK/ITK inhibitor; n = 19) or acalabrutinib (selective BTK inhibitor; n = 13) were collected serially. T cell phenotype, immune function, and CLL cell immunosuppressive capacity were evaluated.Results: Ibrutinib markedly increased CD4+ and CD8+ T cell numbers in CLL patients. This effect was more prominent in effector/effector memory subsets and was not observed with acalabrutinib. Ex vivo studies demonstrated that this may be due to diminished activation-induced cell death through ITK inhibition. PD-1 and CTLA-4 expression was significantly markedly reduced in T cells by both agents. While the number of Treg cells remained unchanged, the ratio of these to conventional CD4+ T cells was reduced with ibrutinib, but not acalabrutinib. Both agents reduced expression of the immunosuppressive molecules CD200 and BTLA as well as IL-10 production by CLL cells.Conclusions: Ibrutinib treatment increased the in vivo persistence of activated T cells, decreased the Treg/CD4+ T cell ratio, and diminished the immune-suppressive properties of CLL cells through BTK-dependent and -independent mechanisms. These features provide a strong rationale for combination immunotherapy approaches with ibrutinib in CLL and other cancers.Trial Registration: ClinicalTrials.gov NCT01589302 and NCT02029443. Samples described here were collected per OSU-0025.Funding: The National Cancer Institute. [ABSTRACT FROM AUTHOR]

The introduction of miR profiling of chronic lymphocytic leukemia (CLL) patients with different cytogenetic profiles and responses to therapy has allowed incorporation of important miR-mRNA interactions into the understanding of disease biology. In this study, we performed miR expression analysis using NanoString nCounter to discover differentially regulated miRs after therapy with the Bruton tyrosine kinase inhibitor ibrutinib. Of the differentially regulated miRs in the discovery set, miR-29c and miR-126 were confirmed using real-time PCR to be upregulated in CLL patient cells with ibrutinib therapy. In the validation set, an inverse correlation was observed between miR-126 levels and expression of its putative target p85β, an isoform of the phosphoinositide 3-kinase p85 regulatory subunit. We found that mRNA for the host gene EGFL7, primary unprocessed miR-126, and mature miR-126 are all downregulated in CLL cells compared to normal B cells. Patients in later stages of disease have a greater decrease in miR-126 expression compared to treatment-naive patients, indicating that lower miR-126 levels may associate with disease progression. Overexpression of miR-126 in leukemia cell lines significantly downregulates p85β expression and decreases activation of prosurvival mitogen-activated protein kinase (MAPK) signaling. These results implicate miR-126 in the pathology of CLL. [ABSTRACT FROM AUTHOR]

Bruton's tyrosine kinase (BTK) is a critical mediator of survival in B-cell neoplasms. Although BTK inhibitors have transformed therapy in chronic lymphocytic leukemia (CLL), patients with high-risk genetics are at risk for relapse and have a poor prognosis. Identification of novel therapeutic strategies for this group of patients is an urgent unmet clinical need, and therapies that targetBTKvia alternative mechanisms may fill this niche. Herein, we identify a set of microRNAs (miRs) that target BTK in primary CLL cells and show that the histone deacetylase (HDAC) repressor complex is recruited to these miR promoters to silence their expression. Targeting the HDACs by using either RNA interference against HDAC1 in CLL or a small molecule inhibitor (HDACi) in CLL and mantle celllymphoma restored the expression of the BTK-targeting miRs with loss of BTK protein and downstream signaling and consequent cell death. We have also made the novel and clinically relevant discovery that inhibition of HDAC induces the BTK-targeting miRs in ibrutinib-sensitive and resistant CLL to effectively reduce both wild-type and C481S-mutant BTK. This finding identifies a novel strategy that may be promising as a therapeutic modality to eliminate the C481S-mutant BTK clone that drives resistance to ibrutinib and provides the rationale for a combination strategy that includes ibrutinib to dually target BTK to suppress its prosurvival signaling. [ABSTRACT FROM AUTHOR]

The authors identified anticancer drugs and biologics given new-drug applications in adults by the U.S. Food and Drug Administration from January 1998 to June 2018 using the Drugs@FDA database. Highlights include extraction and evaluation of trial data by two independent reviewers, the use of multivariable stepwise logistic regression to assess for trial attributes linked with cardiovascular disease (CVD) exclusion, and the reason why the number of excluded CVD patients could not be determined.

Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy is highly promising but requires robust T-cell expansion and engraftment. A T-cell defect in chronic lymphocytic leukemia (CLL) due to disease and/or therapy impairs ex vivo expansion and response to CAR T cells. To evaluate the effect of ibrutinib treatment on the T-cell compartment in CLL as it relates to CAR T-cell generation, we examined the phenotype and function of T cells in a cohort of CLL patients during their course of treatment with ibrutinib. We found that ≥5 cycles of ibrutinib therapy improved the expansion of CD19-directed CAR T cells (CTL019), in association with decreased expression of the immunosuppressive molecule programmed cell death 1 on T cells and of CD200 on B-CLL cells. In support of these findings, we observed that 3 CLL patients who had been treated with ibrutinib for ≥1 year at the time of T-cell collection had improved ex vivo and in vivo CTL019 expansion, which correlated positively together and with clinical response. Lastly, we show that ibrutinib exposure does not impair CAR T-cell function in vitro but does improve CAR T-cell engraftment, tumor clearance, and survival in human xenograft models of resistant acute lymphocytic leukemia and CLL when administered concurrently. Our collective findings indicate that ibrutinib enhances CAR T-cell function and suggest that clinical trials with combination therapy are warranted. Our studies demonstrate that improved T-cell function may also contribute to the efficacy of ibrutinib in CLL. [ABSTRACT FROM AUTHOR]

Background: Irreversible inhibition of Bruton's tyrosine kinase (BTK) by ibrutinib represents an important therapeutic advance for the treatment of chronic lymphocytic leukemia (CLL). However, ibrutinib also irreversibly inhibits alternative kinase targets, which potentially compromises its therapeutic index. Acalabrutinib (ACP-196) is a more selective, irreversible BTK inhibitor that is specifically designed to improve on the safety and efficacy of first-generation BTK inhibitors.Methods: In this uncontrolled, phase 1-2, multicenter study, we administered oral acalabrutinib to 61 patients who had relapsed CLL to assess the safety, efficacy, pharmacokinetics, and pharmacodynamics of acalabrutinib. Patients were treated with acalabrutinib at a dose of 100 to 400 mg once daily in the dose-escalation (phase 1) portion of the study and 100 mg twice daily in the expansion (phase 2) portion.Results: The median age of the patients was 62 years, and patients had received a median of three previous therapies for CLL; 31% had chromosome 17p13.1 deletion, and 75% had unmutated immunoglobulin heavy-chain variable genes. No dose-limiting toxic effects occurred during the dose-escalation portion of the study. The most common adverse events observed were headache (in 43% of the patients), diarrhea (in 39%), and increased weight (in 26%). Most adverse events were of grade 1 or 2. At a median follow-up of 14.3 months, the overall response rate was 95%, including 85% with a partial response and 10% with a partial response with lymphocytosis; the remaining 5% of patients had stable disease. Among patients with chromosome 17p13.1 deletion, the overall response rate was 100%. No cases of Richter's transformation (CLL that has evolved into large-cell lymphoma) and only one case of CLL progression have occurred.Conclusions: In this study, the selective BTK inhibitor acalabrutinib had promising safety and efficacy profiles in patients with relapsed CLL, including those with chromosome 17p13.1 deletion. (Funded by the Acerta Pharma and others; ClinicalTrials.gov number, NCT02029443.). [ABSTRACT FROM AUTHOR]

The proteasome complex degrades proteins involved in a variety of cellular processes and is a powerful therapeutic target in several malignancies. Carfilzomib is a potent proteasome inhibitor which induces rapid chronic lymphocytic leukemia (CLL) cell apoptosisin vitro. We conducted a phase I dose-escalation trial to determine the safety and tolerability of carfilzomib in relapsed/refractory CLL or small lymphocytic lymphoma (SLL). Nineteen patients were treated with carfilzomib initially at 20 mg/m2, then escalated in four cohorts (27, 36, 45 and 56 mg/m2) on days 1, 2, 8, 9, 15 and 16 of 28-day cycles. Therapy was generally well tolerated, and no dose limiting toxicities were observed. The most common hematologic toxicities were thrombocytopenia and neutropenia. All patients evaluable for response had stable disease, including patients with del17p13 and fludarabine-resistant disease. This trial shows acceptable tolerability and limited preliminary efficacy of carfilzomib in CLL and SLL. [ABSTRACT FROM AUTHOR]

Ibrutinib represents a therapeutic advance in chronic lymphocytic leukemia (CLL) but as monotherapy produces few complete remissions in previously treated patients. Anti-CD20 antibodies have improved response and progression-free survival (PFS) when combined with chemotherapy. We evaluated the safety and activity of adding ofatumumab to ibrutinib in 3 different administration sequences. Patients with CLL/small lymphocytic lymphoma (SLL), prolymphocytic leukemia, or Richter's transformation who failed ≥2 prior therapies were enrolled. Patients received ibrutinib 420 mg daily and 12 doses of ofatumumab 300/2000 mg in 3 schedules: ibrutinib lead-in (group 1; n = 27), concurrent start (group 2; n = 20), or ofatumumab lead-in (group 3; n = 24). Seventy-one patients were treated; most had high-risk disease including del(17)(p13.1) (44%) or del(11)(q22.3) (31%). The most frequent adverse events (any grade) were diarrhea (70%), infusion-related reaction (45%), and peripheral sensory neuropathy (44%). Overall response rates in CLL/SLL patients (n = 66) were 100%, 79%, and 71% in groups 1, 2, and 3, respectively. Estimated 12-month PFSs for all patients were 89%, 85%, and 75%, respectively. Four patients in group 3 progressed prior to receiving ibrutinib. This study demonstrates the tolerability and clinical activity of this combination with quicker time to best response than single-agent ibrutinib and with durable responses. This trial was registered at www.clinicaltrials.gov as #NCT01217749. [ABSTRACT FROM AUTHOR]

A jumping translocation (JT) is a rare cytogenetic aberration that can occur in haematological malignancy. It involves the translocation of the same fragment of donor chromosome onto two or more recipient chromosomes, typically in different cells. In this study, we describe the first series of chronic lymphocytic leukaemia (CLL) patients with JTs reported to date. Following a review of 878 CLL patient karyotypes, we identified 26 patients (3%) with 97 JTs. The most commonly occurring breakpoint in these translocations was 17p11.2. Loss of TP53 was identified prior to or at the same time as JT in 23 of 26 patients (88%). All patients eventually developed a complex karyotype. All but one patient has required treatment for CLL, with estimated median time to treatment of 11.5 months. This study establishes JTs as a recurrent abnormality found in CLL patients with aggressive disease. JTs contribute to complex karyotypes and, in many cases, are involved in chromosomal rearrangements that result in loss of the tumour suppressor gene TP53. [ABSTRACT FROM AUTHOR]