Follow-up from the A041202 study shows continued efficacy of ibrutinib regimens for older adults with CLL.

ABSTRACT: A041202 (NCT01886872) is a phase 3 study comparing bendamustine plus rituximab (BR) with ibrutinib and the combination of ibrutinib plus rituximab (IR) in previously untreated older patients with chronic lymphocytic leukemia (CLL). The initial results showed that ibrutinib-containing regimens had superior progression-free survival (PFS) and rituximab did not add additional benefits. Here we present an updated analysis. With a median follow-up of 55 months, the median PFS was 44 months (95% confidence interval [CI], 38-54) for BR and not yet reached in either ibrutinib-containing arm. The 48-month PFS estimates were 47%, 76%, and 76% for BR, ibrutinib, and IR, respectively. The benefit of ibrutinib regimens over chemoimmunotherapy was consistent across subgroups of patients defined by TP53 abnormalities, del(11q), complex karyotype, and immunoglobulin heavy chain variable region (IGHV). No significant interaction effects were observed between the treatment arm and del(11q), the complex karyotype, or IGHV. However, a greater difference in PFS was observed among the patients with TP53 abnormalities. There was no difference in the overall survival. Notable adverse events with ibrutinib included atrial fibrillation (afib) and hypertension. Afib was observed in 11 patients (pts) on BR (3%) and 67 pts on ibrutinib (18%). All-grade hypertension was observed in 95 pts on BR (27%) and 263 pts on ibrutinib (55%). These data show that ibrutinib regimens prolong PFS compared with BR for older patients with treatment-naïve CLL. These benefits were observed across subgroups, including high-risk groups. Strikingly, within the ibrutinib arms, there was no inferior PFS for patients with abnormalities in TP53, the highest risk feature observed in CLL. These data continue to demonstrate the efficacy of ibrutinib in treatment-naïve CLL.

Lisocabtagene maraleucel in chronic lymphocytic leukaemia and small lymphocytic lymphoma (TRANSCEND CLL 004): a multicentre, open-label, single-arm, phase 1-2 study.

BACKGROUND: Patients with relapsed or refractory chronic lymphocytic leukaemia or small lymphocytic lymphoma for whom treatment has failed with both Bruton tyrosine kinase (BTK) inhibitor and venetoclax have few treatment options and poor outcomes. We aimed to evaluate the efficacy and safety of lisocabtagene maraleucel (liso-cel) at the recommended phase 2 dose in patients with relapsed or refractory chronic lymphocytic leukaemia or small lymphocytic lymphoma. METHODS: We report the primary analysis of TRANSCEND CLL 004, an open-label, single-arm, phase 1-2 study conducted in the USA. Patients aged 18 years or older with relapsed or refractory chronic lymphocytic leukaemia or small lymphocytic lymphoma and at least two previous lines of therapy, including a BTK inhibitor, received an intravenous infusion of liso-cel at one of two target dose levels: 50 × 106 (dose level 1) or 100 × 106 (dose level 2, DL2) chimeric antigen receptor-positive T cells. The primary endpoint was complete response or remission (including with incomplete marrow recovery), assessed by independent review according to the 2018 International Workshop on Chronic Lymphocytic Leukemia criteria, in efficacy-evaluable patients with previous BTK inhibitor progression and venetoclax failure (the primary efficacy analysis set) at DL2 (null hypothesis of ≤5%). This trial is registered with ClinicalTrials.gov, NCT03331198. FINDINGS: Between Jan 2, 2018, and June 16, 2022, 137 enrolled patients underwent leukapheresis at 27 sites in the USA. 117 patients received liso-cel (median age 65 years [IQR 59-70]; 37 [32%] female and 80 [68%] male; 99 [85%] White, five [4%] Black or African American, two [2%] other races, and 11 [9%] unknown race; median of five previous lines of therapy [IQR 3-7]); all 117 participants had received and had treatment failure on a previous BTK inhibitor. A subset of patients had also experienced venetoclax failure (n=70). In the primary efficacy analysis set at DL2 (n=49), the rate of complete response or remission (including with incomplete marrow recovery) was statistically significant at 18% (n=9; 95% CI 9-32; p=0·0006). In patients treated with liso-cel, grade 3 cytokine release syndrome was reported in ten (9%) of 117 (with no grade 4 or 5 events) and grade 3 neurological events were reported in 21 (18%; one [1%] grade 4, no grade 5 events). Among 51 deaths on the study, 43 occurred after liso-cel infusion, of which five were due to treatment-emergent adverse events (within 90 days of liso-cel infusion). One death was related to liso-cel (macrophage activation syndrome-haemophagocytic lymphohistiocytosis). INTERPRETATION: A single infusion of liso-cel was shown to induce complete response or remission (including with incomplete marrow recovery) in patients with relapsed or refractory chronic lymphocytic leukaemia or small lymphocytic lymphoma, including patients who had experienced disease progression on a previous BTK inhibitor and venetoclax failure. The safety profile was manageable. FUNDING: Juno Therapeutics, a Bristol-Myers Squibb Company.

Efficacy of venetoclax plus rituximab for relapsed CLL: 5-year follow-up of continuous or limited- duration therapy.

We report long-term follow-up of the phase 1b study of venetoclax and rituximab (VenR) in patients with relapsed chronic lymphocytic leukemia (CLL), including outcomes with continuous or limited-duration therapy. Patients received venetoclax daily (200-600 mg) and rituximab over 6 months and then received venetoclax monotherapy. Patients achieving complete response (CR), CR with incomplete marrow recovery (CRi), or undetectable minimal residual disease (uMRD) assessed by flow cytometry (<10-4 cutoff) were allowed, but not required, to discontinue therapy, while remaining in the study and could be retreated with VenR upon progression. Median follow-up for all patients (N = 49) was 5.3 years. Five-year rates (95% CI) for overall survival, progression-free survival, and duration of response were 86% (72-94), 56% (40-70), and 58% (40-73), respectively. Of the 33 deep responders (CR/CRi or uMRD), 14 remained on venetoclax monotherapy (continuous therapy), and 19 stopped venetoclax therapy (limited-duration therapy) after a median of 1.4 years. Five-year estimates of ongoing response were similar between continuous (71%; 95% CI, 39-88) or limited-duration therapy (79% [49-93]). Six of 19 patients in the latter group had subsequent disease progression, all >2 years off venetoclax (range, 2.1-6.4). Four patients were retreated with VenR, with partial responses observed in the 3 evaluable to date. VenR induced deep responses that were highly durable with either continuous or limited-duration therapy. Retreatment with VenR induced responses in patients with CLL progression after discontinuing therapy. Continuous exposure to venetoclax in deep responders does not appear to provide incremental benefit.

Natural history of monoclonal B-cell lymphocytosis among relatives in CLL families.

Chronic lymphocytic lymphoma (CLL) has one of the highest familial risks among cancers. Monoclonal B-cell lymphocytosis (MBL), the precursor to CLL, has a higher prevalence (13%-18%) in families with 2 or more members with CLL compared with the general population (5%-12%). Although, the rate of progression to CLL for high-count MBLs (clonal B-cell count ≥500/µL) is ∼1% to 5%/y, no low-count MBLs have been reported to progress to date. We report the incidence and natural history of MBL in relatives from CLL families. In 310 CLL families, we screened 1045 relatives for MBL using highly sensitive flow cytometry and prospectively followed 449 of them. MBL incidence was directly age- and sex-adjusted to the 2010 US population. CLL cumulative incidence was estimated using Kaplan-Meier survival curves. At baseline, the prevalence of MBL was 22% (235/1045 relatives). After a median follow-up of 8.1 years among 449 relatives, 12 individuals progressed to CLL with a 5-year cumulative incidence of 1.8%. When considering just the 139 relatives with low-count MBL, the 5-year cumulative incidence increased to 5.7%. Finally, 264 had no MBL at baseline, of whom 60 individuals subsequently developed MBL (2 high-count and 58 low-count MBLs) with an age- and sex-adjusted incidence of 3.5% after a median of 6 years of follow-up. In a screening cohort of relatives from CLL families, we reported progression from normal-count to low-count MBL to high-count MBL to CLL, demonstrating that low-count MBL precedes progression to CLL. We estimated a 1.1% annual rate of progression from low-count MBL, which is in excess of that in the general population.

Phase 2 study of the safety and efficacy of umbralisib in patients with CLL who are intolerant to BTK or PI3Kδ inhibitor therapy.

Intolerance is the most common reason for kinase inhibitor (KI) discontinuation in chronic lymphocytic leukemia (CLL). Umbralisib, a novel highly selective phosphatidylinositol 3-kinase Î´ (PI3Kδ)/CK1ε inhibitor, is active and well tolerated in CLL patients. In this phase 2 trial (NCT02742090), umbralisib was initiated at 800 mg/d in CLL patients requiring therapy, who were intolerant to prior BTK inhibitor (BTKi) or PI3K inhibitor (PI3Ki) therapy, until progression or toxicity. Primary end point was progression-free survival (PFS). Secondary end points included time to treatment failure and safety. DNA was genotyped for CYP3A4, CYP3A5, and CYP2D6 polymorphisms. Fifty-one patients were enrolled (44 BTKi intolerant and 7 PI3Kδi intolerant); median age was 70 years (range, 48-96), with a median of 2 prior lines of therapy (range, 1-7), 24% had del17p and/or TP53 mutation, and 65% had unmutated IGHV. Most common adverse events (AEs) leading to prior KI discontinuation were rash (27%), arthralgia (18%), and atrial fibrillation (16%). Median PFS was 23.5 months (95% CI, 13.1-not estimable), with 58% of patients on umbralisib for a longer duration than prior KI. Most common (≥5%) grade ≥3 AEs on umbralisib (all causality) were neutropenia (18%), leukocytosis (14%), thrombocytopenia (12%), pneumonia (12%), and diarrhea (8%). Six patients (12%) discontinued umbralisib because of an AE. Eight patients (16%) had dose reductions and were successfully rechallenged. These are the first prospective data to confirm that switching from a BTKi or alternate PI3Ki to umbralisib in this BTKi- and PI3Ki-intolerant CLL population can result in durable well-tolerated responses.

DTRMWXHS-12, a novel Bruton tyrosine kinase inhibitor, in combination with everolimus and pomalidomide in patients with relapsed/refractory lymphomas: An open-label, multicenter, phase 1a/1b study.

Preclinical studies have shown augmented activity when combining Bruton tyrosine kinase inhibitors (BTKi) with inhibitors of mammalian target of rapamycin (mTOR) and immunomodulatory agents (IMiD). We conducted a phase 1, open-label study at five centers in USA to evaluate the safety of triplet BTKi/mTOR/IMiD therapy. Eligible patients were adults aged 18 years or older with relapsed/refractory CLL, B cell NHL, or Hodgkin lymphoma. Our dose escalation study used an accelerated titration design and moved sequentially from single agent BTKi (DTRMWXHS-12), doublet (DTRMWXHS-12 + everolimus), and then to triplet therapy (DTRMWXHS-12 + everolimus + pomalidomide). All drugs were dosed once daily on days 1-21 of each 28-day cycle. The primary goal was to establish the recommended phase 2 dose of the triplet combination. Between September 27, 2016, and July 24, 2019, a total of 32 patients with a median age of 70 years (range 46 to 94 years) were enrolled. No MTD was identified for monotherapy and the doublet combination. The MTD for the triplet combination was determined to be DTRMWXHS-12 200 mg + everolimus 5 mg + pomalidomide 2 mg. Responses across all studied cohorts were seen in 13 of 32 (41.9%). Combining DTRMWXHS-12 with everolimus and pomalidomide is tolerable and shows clinical activity. Additional trials could confirm benefit of this all-oral combination therapy for relapsed/refractory lymphomas.

Zanubrutinib versus bendamustine and rituximab in untreated chronic lymphocytic leukaemia and small lymphocytic lymphoma (SEQUOIA): a randomised, controlled, phase 3 trial.

BACKGROUND: Zanubrutinib is a next-generation, selective Bruton tyrosine kinase inhibitor with efficacy in relapsed chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL). We compared zanubrutinib with bendamustine-rituximab to determine its effectiveness as frontline therapy in patients with CLL or SLL. METHODS: We conducted an open-label, multicentre, phase 3 study at 153 academic or community hospitals in 14 countries and regions. Eligible patients had untreated CLL or SLL requiring treatment as per International Workshop on CLL criteria; were aged 65 years or older, or 18 years or older and had comorbidities; and had an Eastern Cooperative Oncology Group performance status score of 0-2. A central interactive web response system randomly assigned patients without del(17)(p13·1) to zanubrutinib (group A) or bendamustine-rituximab (group B) by sequential block method (permutated blocks with a random block size of four). Patients with del(17)(p13·1) were enrolled in group C and received zanubrutinib. Zanubrutinib was administered orally at 160 mg twice per day (28-day cycles); bendamustine at 90 mg/m2 of body surface area on days 1 and 2 for six cycles plus rituximab at 375 mg/m2 of body surface area the day before or on day 1 of cycle 1, and 500 mg/m2 of body surface area on day 1 of cycles 2-6, were administered intravenously. The primary endpoint was progression-free survival per independent review committee in the intention-to-treat population in groups A and B, with minimum two-sided α of 0·05 for superiority. Safety was analysed in all patients who received at least one dose of study treatment. The study is registered with ClinicalTrials.gov, NCT03336333, and is closed to recruitment. FINDINGS: Between Oct 31, 2017, and July 22, 2019, 590 patients were enrolled; patients without del(17)(p13·1) were randomly assigned to zanubrutinib (group A; n=241) or bendamustine-rituximab (group B; n=238). At median follow-up of 26·2 months (IQR 23·7-29·6), median progression-free survival per independent review committee was not reached in either group (group A 95% CI not estimable [NE] to NE; group B 28·1 months to NE). Progression-free survival was significantly improved in group A versus group B (HR 0·42 [95% CI 0·28 to 0·63]; two-sided p<0·0001). The most common grade 3 or worse adverse event was neutropenia (27 [11%] of 240 patients in group A, 116 [51%] of 227 in group B, and 17 [15%] of 111 patients in group C). Serious adverse events occurred in 88 (37%) of 240 patients in group A, 113 (50%) of 227 patients in group B, and 45 (41%) of 111 patients in group C. Adverse events leading to death occurred in 11 (5%) of 240 patients in group A, 12 (5%) of 227 patients in group B, and three (3%) of 111 patients in group C, most commonly due to COVID-19 (four [2%] of 240 patients in group A), diarrhoea, and aspiration pneumonia (two each [1%] of 227 patients in group B). INTERPRETATION: Zanubrutinib significantly improved progression-free survival versus bendamustine-rituximab, with an acceptable safety profile consistent with previous studies. These data support zanubrutinib as a potential new treatment option for untreated CLL and SLL. FUNDING: BeiGene.

Outcomes of COVID-19 in patients with CLL: a multicenter international experience.

Given advanced age, comorbidities, and immune dysfunction, chronic lymphocytic leukemia (CLL) patients may be at particularly high risk of infection and poor outcomes related to coronavirus disease 2019 (COVID-19). Robust analysis of outcomes for CLL patients, particularly examining effects of baseline characteristics and CLL-directed therapy, is critical to optimally manage CLL patients through this evolving pandemic. CLL patients diagnosed with symptomatic COVID-19 across 43 international centers (n = 198) were included. Hospital admission occurred in 90%. Median age at COVID-19 diagnosis was 70.5 years. Median Cumulative Illness Rating Scale score was 8 (range, 4-32). Thirty-nine percent were treatment naive ("watch and wait"), while 61% had received ≥1 CLL-directed therapy (median, 2; range, 1-8). Ninety patients (45%) were receiving active CLL therapy at COVID-19 diagnosis, most commonly Bruton tyrosine kinase inhibitors (BTKi's; n = 68/90 [76%]). At a median follow-up of 16 days, the overall case fatality rate was 33%, though 25% remain admitted. Watch-and-wait and treated cohorts had similar rates of admission (89% vs 90%), intensive care unit admission (35% vs 36%), intubation (33% vs 25%), and mortality (37% vs 32%). CLL-directed treatment with BTKi's at COVID-19 diagnosis did not impact survival (case fatality rate, 34% vs 35%), though the BTKi was held during the COVID-19 course for most patients. These data suggest that the subgroup of CLL patients admitted with COVID-19, regardless of disease phase or treatment status, are at high risk of death. Future epidemiologic studies are needed to assess severe acute respiratory syndrome coronavirus 2 infection risk, these data should be validated independently, and randomized studies of BTKi's in COVID-19 are needed to provide definitive evidence of benefit.

Ibrutinib Regimens versus Chemoimmunotherapy in Older Patients with Untreated CLL.

BACKGROUND: Ibrutinib has been approved by the Food and Drug Administration for the treatment of patients with untreated chronic lymphocytic leukemia (CLL) since 2016 but has not been compared with chemoimmunotherapy. We conducted a phase 3 trial to evaluate the efficacy of ibrutinib, either alone or in combination with rituximab, relative to chemoimmunotherapy. METHODS: Patients 65 years of age or older who had untreated CLL were randomly assigned to receive bendamustine plus rituximab, ibrutinib, or ibrutinib plus rituximab. The primary end point was progression-free survival. The Alliance Data and Safety Monitoring Board made the decision to release the data after the protocol-specified efficacy threshold had been met. RESULTS: A total of 183 patients were assigned to receive bendamustine plus rituximab, 182 to receive ibrutinib, and 182 to receive ibrutinib plus rituximab. Median progression-free survival was reached only with bendamustine plus rituximab. The estimated percentage of patients with progression-free survival at 2 years was 74% with bendamustine plus rituximab and was higher with ibrutinib alone (87%; hazard ratio for disease progression or death, 0.39; 95% confidence interval [CI], 0.26 to 0.58; P<0.001) and with ibrutinib plus rituximab (88%; hazard ratio, 0.38; 95% CI, 0.25 to 0.59; P<0.001). There was no significant difference between the ibrutinib-plus-rituximab group and the ibrutinib group with regard to progression-free survival (hazard ratio, 1.00; 95% CI, 0.62 to 1.62; P=0.49). With a median follow-up of 38 months, there was no significant difference among the three treatment groups with regard to overall survival. The rate of grade 3, 4, or 5 hematologic adverse events was higher with bendamustine plus rituximab (61%) than with ibrutinib or ibrutinib plus rituximab (41% and 39%, respectively), whereas the rate of grade 3, 4, or 5 nonhematologic adverse events was lower with bendamustine plus rituximab (63%) than with the ibrutinib-containing regimens (74% with each regimen). CONCLUSIONS: Among older patients with untreated CLL, treatment with ibrutinib was superior to treatment with bendamustine plus rituximab with regard to progression-free survival. There was no significant difference between ibrutinib and ibrutinib plus rituximab with regard to progression-free survival. (Funded by the National Cancer Institute and Pharmacyclics; ClinicalTrials.gov number, NCT01886872 .).

Hodgkin lymphoma arising in patients with chronic lymphocytic leukemia: outcomes from a large multi-center collaboration.

Chronic lymphocytic leukemia (CLL) patients who develop Hodgkin lymphoma (HL) have limited survival. No current therapeutic standard of care exists. We conducted a multi-center retrospective study of patients with Hodgkin Transformation (HT) of CLL. Clinicobiologic characteristics, treatment type, and survival outcomes were analyzed and compared with historic case series. Ninety-four patients were identified. Median age at HT was 67 years (range, 38-85). Median time from CLL diagnosis to HT was 5.5 years (range, 0-20.2). Prior to HT, patients received a median of 2 therapies for CLL (range, 0-12). As initial therapy for HT, 61% (n=62) received ABVD-based regimens (adriamycin, bleomycin, vinblastine, and dacarbazine). Seven (7%) patients received hematopoietic cell transplantation (HCT) while in first complete remission (CR1). The median number of treatments for HT per patient was 1 (range, 0-5) with 59 (61%) patients only receiving one line of therapy. After HT, patients had a median follow-up of 1.6 years (range, 0-15.1). Two-year overall survival (OS) after HT diagnosis was 72% (95%CI 62-83%). The patients who received standard ABVD-based therapy had a median OS of 13.2 years. Although limited by small sample size, the patients who underwent HCT for HT in CR1 had a similar 2-year OS (n=7; 67%) compared to patients who did not undergo HCT for HT in CR1 (n=87; 72%; p=0.46). In this multi-center study, HT patients treated with ABVD-based regimens had prolonged survival supporting the use of these regimens as standard of care for these patients.

The efficacy and safety of venetoclax therapy in elderly patients with relapsed, refractory chronic lymphocytic leukaemia.

Elderly chronic lymphocytic leukaemia (CLL) patients treated outside of trials have notably greater toxicity with the Bruton's tyrosine kinase inhibitor ibrutinib compared to younger patients. It is not known whether the same holds true for the B-cell lymphoma 2 inhibitor venetoclax. We provide a comprehensive analysis of key safety measures and efficacy in 342 patients comparing age categories ≥75 and <75 years treated in the relapsed, refractory non-trial setting. We demonstrate that venetoclax has equivalent efficacy and safety in relapsed/refractory CLL patients who are elderly, the majority of whom are previous ibrutinib-exposed and therefore may otherwise have few clear therapeutic options.

SET alpha and SET beta mRNA isoforms in chronic lymphocytic leukaemia.

Alteration in RNA splicing is implicated in carcinogenesis and progression. Mutations in spliceosome genes and alternative splicing of other genes have been noted in chronic lymphocytic leukaemia (CLL), a common B cell malignancy with heterogeneous outcomes. We previously demonstrated that differences in the amount of SET oncoprotein (a physiological inhibitor of the serine/threonine phosphatase, PP2A) is associated with clinical aggressiveness in patients with CLL. It is unknown if alternative splicing of gene transcripts regulating kinases and phosphatases affects disease pathobiology and CLL progression. We show here for the first time that mRNA levels of the alternatively spliced SET isoforms, SETA and SETB (SETα and SETß), significantly correlate with disease severity (overall survival and time-to-first-treatment) in CLL patients. In addition, we demonstrate that relative increase of SETA to SETB mRNA can discriminate patients with a more aggressive disease course within the otherwise favourable CLL risk classifications of IGHV mutated and favourable hierarchical fluorescence in situ hybridisation groups. We validate our finding by showing comparable relationships of SET mRNA with disease outcomes using samples from an independent CLL cohort from a separate institution. These findings indicate that alternative splicing of SET, and potentially other signalling cascade molecules, influences CLL biology and patient outcomes.

Umbralisib, a novel PI3Kδ and casein kinase-1ε inhibitor, in relapsed or refractory chronic lymphocytic leukaemia and lymphoma: an open-label, phase 1, dose-escalation, first-in-human study.

BACKGROUND: Umbralisib (TGR-1202) is a novel next-generation inhibitor of phosphatidylinositol 3-kinase (PI3K) isoform p110δ (PI3Kδ), which is structurally distinct from other PI3Kδ inhibitors and shows improved isoform selectivity. Umbralisib also uniquely inhibits casein kinase-1ε, a major regulator of protein translation. The aim of this first-in-human phase 1 study was to establish the safety and preliminary activity profile of umbralisib in patients with haematological malignancies. METHODS: We did an open-label, phase 1, dose-escalation study at seven clinics in the USA. We recruited patients aged at least 18 years with relapsed or refractory chronic lymphocytic leukaemia or small lymphocytic lymphoma, B-cell and T-cell non-Hodgkin lymphoma, or Hodgkin's lymphoma, who had received one or more previous lines of therapy, with measurable and assessable disease, and adequate organ system function. Patients self-administered an umbralisib oral tablet once per day in 28-day cycles, with dose escalation done in a traditional 3 + 3 design to establish safety and determine the maximum tolerated dose. In initial cohorts, patients took umbralisib in a fasting state at a starting dose of 50 mg, increasing to 100, 200, 400, 800, 1200, and 1800 mg until the maximum tolerated dose was reached, or the maximal dose cohort was accrued without a dose-limiting toxicity. Subsequent cohorts self-administered a micronised formulation of umbralisib tablet in a fed state at an initial dose of 200 mg, increased in increments to 400, 800, 1200, and 1800 mg until the maximum tolerated dose or the maximal dose level was accrued. In August, 2014, all patients still on study were transitioned to 800 mg of the micronised formulation and dosing of the initial formulation was discontinued. The primary endpoints of the study were investigator-assessed safety in all treated patients (the safety population), the maximum tolerated dose, and the pharmacokinetics of umbralisib. Secondary endpoints included preliminary assessments of anti-cancer activity (objective responses and duration of response). Follow-up stopped for a patient once they discontinued therapy. This study has been completed and is registered with ClinicalTrials.gov, number NCT01767766. FINDINGS: Between Jan 17, 2013, and Jan 14, 2016, we enrolled and treated 90 patients with umbralisib. The median duration of treatment and follow-up was 4·7 cycles (IQR 2·0-14·0) or 133 days (IQR 55-335). The most common treatment-emergent adverse events irrespective of causality were diarrhoea (in 39 [43%] of 90 patients), nausea (38 [42%]), and fatigue (28 [31%]). The most common grade 3 or 4 adverse events were neutropenia (in 12 [13%] patients), anaemia (eight [9%]) and thrombocytopenia (six [7%]). Serious adverse events considered at least possibly related to umbralisib occurred in seven patients: pneumonia in three (3%) patients, lung infection in one (1%), febrile neutropenia in one (1%), and colitis in two (2%), one of whom also had febrile neutropenia. The maximum tolerated dose was 1200 mg of the micronised formulation, with 800 mg of this formulation selected as the recommended phase 2 dose. Both cases of colitis occurred at above the recommended phase 2 dose. 33 (37%) of the 90 patients enrolled had an objective response to treatment with umbralisib. INTERPRETATION: Umbralisib was well tolerated and showed preliminary signs of activity in patients with relapsed or refractory haematological malignancies. The safety profile of umbralisib in this phase 1 study was distinct from that of other PI3Kδ inhibitors, with fewer occurrences of autoimmune-like toxicities such as colitis. These findings warrant further evaluation of this agent in this setting. FUNDING: TG Therapeutics.

Toxicities and outcomes of 616 ibrutinib-treated patients in the United States: a real-world analysis.

Clinical trials that led to ibrutinib's approval for the treatment of chronic lymphocytic leukemia showed that its side effects differ from those of traditional chemotherapy. Reasons for discontinuation in clinical practice have not been adequately studied. We conducted a retrospective analysis of chronic lymphocytic leukemia patients treated with ibrutinib either commercially or on clinical trials. We aimed to compare the type and frequency of toxicities reported in either setting, assess discontinuation rates, and evaluate outcomes. This multicenter, retrospective analysis included ibrutinib-treated chronic lymphocytic leukemia patients at nine United States cancer centers or from the Connect® Chronic Lymphocytic Leukemia Registry. We examined demographics, dosing, discontinuation rates and reasons, toxicities, and outcomes. The primary endpoint was progression-free survival. Six hundred sixteen ibrutinib-treated patients were identified. A total of 546 (88%) patients were treated with the commercial drug. Clinical trial patients were younger (mean age 58 versus 61 years, P=0.01) and had a similar time from diagnosis to treatment with ibrutinib (mean 85 versus 87 months, P=0.8). With a median follow-up of 17 months, an estimated 41% of patients discontinued ibrutinib (median time to ibrutinib discontinuation was 7 months). Notably, ibrutinib toxicity was the most common reason for discontinuation in all settings. The median progression-free survival and overall survival for the entire cohort were 35 months and not reached (median follow-up 17 months), respectively. In the largest reported series on ibrutinib- treated chronic lymphocytic leukemia patients, we show that 41% of patients discontinued ibrutinib. Intolerance as opposed to chronic lymphocytic leukemia progression was the most common reason for discontinuation. Outcomes remain excellent and were not affected by line of therapy or whether patients were treated on clinical studies or commercially. These data strongly argue in favor of finding strategies to minimize ibrutinib intolerance so that efficacy can be further maximized. Future clinical trials should consider time-limited therapy approaches, particularly in patients achieving a complete response, in order to minimize ibrutinib exposure.

Real-world outcomes and management strategies for venetoclax-treated chronic lymphocytic leukemia patients in the United States.

Venetoclax is a BCL2 inhibitor approved for 17p-deleted relapsed/refractory chronic lymphocytic leukemia with activity following kinase inhibitors. We conducted a multicenter retrospective cohort analysis of patients with chronic lymphocytic leukemia treated with venetoclax to describe outcomes, toxicities, and treatment selection following venetoclax discontinuation. A total of 141 chronic lymphocytic leukemia patients were included (98% relapsed/refractory). Median age at venetoclax initiation was 67 years (range 37-91), median prior therapies was 3 (0-11), 81% unmutated IGHV, 45% del(17p), and 26.8% complex karyotype (≥ 3 abnormalities). Prior to venetoclax initiation, 89% received a B-cell receptor antagonist. For tumor lysis syndrome prophylaxis, 93% received allopurinol, 92% normal saline, and 45% rasburicase. Dose escalation to the maximum recommended dose of 400 mg daily was achieved in 85% of patients. Adverse events of interest included neutropenia in 47.4%, thrombocytopenia in 36%, tumor lysis syndrome in 13.4%, neutropenic fever in 11.6%, and diarrhea in 7.3%. The overall response rate to venetoclax was 72% (19.4% complete remission). With a median follow up of 7 months, median progression free survival and overall survival for the entire cohort have not been reached. To date, 41 venetoclax treated patients have discontinued therapy and 24 have received a subsequent therapy, most commonly ibrutinib. In the largest clinical experience of venetoclax-treated chronic lymphocytic leukemia patients, the majority successfully completed and maintained a maximum recommended dose. Response rates and duration of response appear comparable to clinical trial data. Venetoclax was active in patients with mutations known to confer ibrutinib resistance. Optimal sequencing of newer chronic lymphocytic leukemia therapies requires further study.

Outcomes of front-line ibrutinib treated CLL patients excluded from landmark clinical trial.

Ibrutinib demonstrated superior response rates and survival for treatment-naïve chronic lymphocytic leukemia (CLL) patients in a pivotal study that excluded patients younger than 65 (<65) and/or with chromosome 17p13 deletion (del[17p13]). We examined outcomes and toxicities of CLL patients who would have been excluded from the pivotal study, specifically <65 and/or those with del[17p13]. This multicenter, retrospective cohort study examined CLL patients treated with front-line ibrutinib at 20 community and academic centers, categorizing them based on key inclusion criteria for the RESONATE-2 trial: <65 vs ≥65 and present vs absent del[17p13]. Of 391 included patients, 57% would have been excluded from the pivotal study. Forty-one percent of our cohort was <65, and 30% had del(17p13). Patients <65 were more likely to start 420 mg of ibrutinib daily; those who started at reduced doses had inferior PFS. The most common adverse events were arthralgias, fatigue, rash, bruising, and diarrhea. Twenty-four percent discontinued ibrutinib at 13.8 months median follow-up; toxicity was the most common reason for discontinuation, though progression and/or transformation accounted for a larger proportion of discontinuations in <65 and those with del(17p13). Response rates were similar for <65 and those with del(17p13). However, patients with del(17p13) had inferior PFS and OS. Ibrutinib in the front-line setting has extended beyond the population in which it was initially studied and approved. This study highlights and compares important differences in ibrutinib dosing, treatment interruptions, toxicities, reasons for discontinuation, and survival outcomes in two important patient populations not studied in RESONATE-2.

Venetoclax plus rituximab in relapsed or refractory chronic lymphocytic leukaemia: a phase 1b study.

BACKGROUND: Selective BCL2 inhibition with venetoclax has substantial activity in patients with relapsed or refractory chronic lymphocytic leukaemia. Combination therapy with rituximab enhanced activity in preclinical models. The aim of this study was to assess the safety, pharmacokinetics, and activity of venetoclax in combination with rituximab. METHODS: Adult patients with relapsed or refractory chronic lymphocytic leukaemia (according to the 2008 Modified International Workshop on CLL guidelines) or small lymphocytic lymphoma were eligible for this phase 1b, dose-escalation trial. The primary outcomes were to assess the safety profile, to determine the maximum tolerated dose, and to establish the recommended phase 2 dose of venetoclax when given in combination with rituximab. Secondary outcomes were to assess the pharmacokinetic profile and analyse efficacy, including overall response, duration of response, and time to tumour progression. Minimal residual disease was a protocol-specified exploratory objective. Central review of the endpoints was not done. Venetoclax was dosed daily using a stepwise escalation to target doses (200-600 mg) and then monthly rituximab commenced (375 mg/m2 in month 1 and 500 mg/m2 in months 2-6). Adverse events were graded according to the National Cancer Institute Common Terminology Criteria for adverse events version 4.0. Protocol-guided drug cessation was allowed for patients who achieved complete response (including complete response with incomplete marrow recovery) or negative bone marrow minimal residual disease. Analyses were done per protocol for all patients who commenced drug and included all patients who received at least one dose of venetoclax. Data were pooled across dose cohorts. Patients are still receiving therapy and follow-up is ongoing. The trial is registered at ClinicalTrials.gov, number NCT01682616. FINDINGS: Between Aug 6, 2012, and May 28, 2014, we enrolled 49 patients. Common grade 1-2 toxicities included upper respiratory tract infections (in 28 [57%] of 49 patients), diarrhoea (27 [55%]), and nausea (25 [51%]). Grade 3-4 adverse events occurred in 37 (76%) of 49 patients; most common were neutropenia (26 [53%]), thrombocytopenia (eight [16%]), anaemia (seven [14%]), febrile neutropenia (six [12%]), and leucopenia (six [12%]). The most common serious adverse events were pyrexia (six [12%]), febrile neutropenia (five [10%]), lower respiratory tract infection, and pneumonia (each three [6%]). Clinical tumour lysis syndrome occurred in two patients (resulting in one death) who initiated venetoclax at 50 mg. After enhancing tumour lysis syndrome prophylaxis measures and commencing venetoclax at 20 mg, clinical tumour lysis syndrome did not occur. The maximum tolerated dose was not identified; the recommended phase 2 dose of venetoclax in combination with rituximab was 400 mg. Overall, 42 (86%) of 49 patients achieved a response, including a complete response in 25 (51%) of 49 patients. 2 year estimates for progression-free survival and ongoing response were 82% (95% CI 66-91) and 89% (95% CI 72-96), respectively. Negative marrow minimal residual disease was attained in 20 (80%) of 25 complete responders and 28 (57%) of 49 patients overall. 13 responders ceased all therapy; among these all 11 minimal residual disease-negative responders remain progression-free off therapy. Two with minimal residual disease-positive complete response progressed after 24 months off therapy and re-attained response after re-initiation of venetoclax. INTERPRETATION: A substantial proportion of patients achieved an overall response with the combination of venetoclax and rituximab including 25 (51%) of 49 patients who achieved a complete response and 28 (57%) of 49 patients who achieved negative marrow minimal residual disease with acceptable safety. The depth and durability of responses observed with the combination offers an attractive potential treatment option for patients with relapsed or refractory chronic lymphocytic leukaemia and could allow some patients to maintain response after discontinuing therapy, a strategy that warrants further investigation in randomised studies. FUNDING: AbbVie Inc and Genentech Inc.