Macrophage- and BCR-derived but not TLR-derived signals support the growth of CLL and Richter syndrome murine models in vivo.

A large amount of circumstantial evidence has accumulated suggesting that Toll-like receptor (TLR) signals are involved in driving chronic lymphocytic leukemia (CLL) cell proliferation, but direct in vivo evidence for this is still lacking. We have now further addressed this possibility by pharmacologically inhibiting or genetically inactivating the TLR pathway in murine CLL and human Richter syndrome (RS) patient-derived xenograft (PDX) cells. Surprisingly, we show that pharmacologic inhibition of TLR signaling by treatment with an IRAK1/4 inhibitor delays the growth of the transplanted malignant cells in recipient mice, but genetic inactivation of the same pathway by CRISPR/Cas9-mediated disruption of IRAK4 or its proximal adaptor MyD88 has no effect. We further show that treatment with the IRAK1/4 inhibitor results in depletion of macrophages and demonstrate that these cells can support the survival and enhance the proliferation of both murine Eµ-TCL1 leukemia and human RS cells. We also show that genetic disruption of the B-cell receptor (BCR) by CRISPR/Cas9 editing of the immunoglobulin M constant region gene inhibits the growth of human RS-PDX cells in vivo, consistent with our previous finding with murine Eµ-TCL1 leukemia cells. Finally, we show that genetic disruption of IRAK4 does not result in negative selection of human CLL cell lines xenografted in immunodeficient mice. The obtained data suggest that TLR signals are unlikely to represent a major driver of CLL/RS cell proliferation and provide further evidence that signals from macrophages and the BCR promote the growth and survival of CLL and RS cells in vivo.

Minimal residual disease-driven treatment intensification with sequential addition of ibrutinib to venetoclax in R/R CLL.

Undetectable measurable residual disease (uMRD) is achievable in patients with chronic lymphocytic leukemia (CLL) with the BCL2-inhibitor venetoclax alone or combined with the Bruton's tyrosine kinase inhibitor ibrutinib. This phase 2, multicenter, MRD-driven study was designed to discontinue treatment upon reaching uMRD4 (<10-4) in patients with relapsed/refractory CLL receiving venetoclax monotherapy or after the addition of ibrutinib. Primary end point of the study was proportion of uMRD4 with venetoclax ± ibrutinib. Secondary end points were overall response rate, partial response, complete response, progression-free survival, duration of response, overall survival, and safety of venetoclax ± ibrutinib. Patients with uMRD4 at Cycle 12 Day 1 discontinued venetoclax. MRD+ patients added ibrutinib and continued both drugs up to Cycle 24 Day 28/uMRD4/progression/toxicity. After Cycle 24 Day 28, MRD+ patients continued ibrutinib. Thirty-eight patients (29% with TP53 aberrations; 79% with unmutated IGHV) started venetoclax. Overall response rate with venetoclax was 36 (95%) of 38 patients (20 complete; 16 partial response). Seventeen patients (45%) with uMRD4 at Cycle 12 Day 1 discontinued venetoclax. Nineteen (55%) MRD+ subjects added ibrutinib. After a median of 7 months (range, 3-10 months) of combined treatment, 16 (84%) of 19 achieved uMRD4, thus stopping both drugs. Two MRD+ patients at Cycle 24 Day 28 continued ibrutinib until progression/toxicity. After a median follow-up of 36.5 months, median progression-free survival was not reached; 10 patients progressed (4 restarted venetoclax, 3 without treatment need, 2 developed Richter transformation, and 1 dropped out). Seven (22%) of 32 patients remain uMRD4 after 3 years of follow-up. Neutropenia was the most frequent grade 3 to 4 adverse event; no grade 5 events occurred on study. This sequential MRD-guided approach led to uMRD4 in 33 (87%) of 38 patients, with venetoclax monotherapy or combined with ibrutinib, delivering treatment combination only in a fraction, and ultimately identifying the few patients benefiting from continuous therapy. This trial was registered at www.clinicaltrials.gov as # NCT04754035.

What is the best treatment strategy before autologous peripheral blood stem cell transplantation in POEMS syndrome?

Autologous peripheral blood stem cell transplantation (aPBSCT) provides optimal outcomes in POEMS syndrome but the definition of the best treatment before aPBSCT remains to be defined because of the rarity of the disease and the heterogeneity of published case series. We collected clinical and laboratory data of patients with POEMS syndrome undergoing aPBSCT from 1998 to 2020 in ten Italian centers. The primary endpoint of the study was to evaluate the impact of prior therapies and mobilization regimen on outcome. We divided the patients into three groups: patients who did not receive any treatment before transplant (15 patients, group A: front-line), patients pre-treated with other agents (14 patients, group B) and patients treated with cyclophosphamide as their mobilizing regimen (16 patients, group C). The three groups did not show differences in terms of demographic and clinical characteristics. All 45 patients underwent aPBSCT after a high-dose melphalan conditioning regimen, with a median follow-up of 77 months (range, 37-169 months). The responses were not statistically different between the three groups (P=0.38). Progression-free and overall survival rates at 6 years were: 70% (95% confidence interval: 55-85%) and 91% (95% confidence interval: 82-99) 65%, respectively, and did not differ between the three groups. The cumulative incidence of transplant-related mortality and relapse was 4% and 36%, respectively. In conclusion, in a relatively large number of patients with POEMS syndrome, undergoing an autologous transplant, pre-treatment and disease status at transplant did not appear to have an impact on major transplant outcomes.

Patients' preferences for chronic lymphocytic leukemia treatment: The CHOICE study.

Chronic lymphocytic leukemia (CLL) therapies differ in efficacy, side effects, route, frequency, and duration of administration. We assessed patient preferences for treatment attributes and evaluated associations with disease stage, treatment line, and socio-demographic characteristics in a cross sectional, observational study conducted at 16 Italian hematology centers. Study visits occurred between February and July 2020; 401 adult patients with CLL (201 Watch and Wait (W&W), 200 treated) participated in a discrete choice experiment (DCE), composed of 8 choices between pairs of treatment profiles with different levels of 5 attributes of currently available CLL treatments (length of response, route and duration of administration, risk of side effects including diarrhea, infections, or organ damage). Health-related quality of life was assessed with the EQ-5D-5L, EORTC QLQ-C30 and QLQ CLL-16. Previously treated patients had longer disease duration (7 vs. 5 years), higher prevalence of serious comorbidities (45.5% vs. 36.2%) and high-risk molecular markers (unmutated IGHV 55.6% vs. 17.1%; TP53 mutation 15.2% vs. 4.0%). Health-related quality of life scores were similar between groups. In the DCE, W&W patients rated "possible occurrence of infections" highest (relative importance [RI] = 36.2%), followed by "treatment and relevant duration" (RI = 28.0%) and "progression-free survival (PFS)" (RI = 16.9%). Previously treated patients rated "treatment and relevant duration" highest (RI = 33.3%), followed by "possible occurrence of infections" (RI = 28.8%), "possible occurrence of organ damage" (RI = 19.4%), and "PFS" (RI = 9.8%). Concern over infection was rated highest overall; unexpectedly PFS was not among the most important criteria in either group, suggesting that the first COVID-19 pandemic wave may have influenced patient preferences and concerns about CLL therapy options.

Ibrutinib as first line therapy in chronic lymphocytic leukemia patients over 80 years old: A retrospective real-life multicenter Italian cohort.

Although chronic lymphocytic leukemia (CLL) predominantly affects the elderly, limited data exists about the outcomes of over 80-year-old patients, usually underrepresented in clinical trials. We conducted a multicenter study enrolling 79 consecutive CLL patients ≥80 years at the time of frontline therapy, all treated with ibrutinib. Nearly 48% of cases exhibited unmutated IGHV genes, 32% 17p deletion, and 39.2% TP53 mutations; 63.3% displayed a cumulative illness rating scale (CIRS) > 6. The overall response rate on ibrutinib, computed in 74/79 patients (5 patients excluded for early withdrawal), was 89.9%. After a median follow-up of 28.9 months, the median progression-free survival (PFS) and overall survival (OS) were 42.5 and 51.8 months, respectively. CIRS>6 and temporary discontinuation of ibrutinib lasting for 7-30 days were the only parameters associated with a significantly shorter PFS and were both relevant in predicting a shorter PFS compared to patients with CIRS≤6 and therapy discontinuation ≤7 days. The most common grade≥3 adverse events were infections (25.5%), neutropenia (10.1%), and anemia (2.5%). Eighteen patients (22.8%) experienced a cardiovascular event, including grade-2 atrial fibrillation (n = 9; 11%), grade-2 hypertension (n = 5; 6%), heart failure (n = 3; 3%), and acute coronary syndrome (n = 1; 1%). Mild bleeding events were observed in 27 patients (34.2%). Ibrutinib was permanently discontinued in 26 patients due to progressive disease (n = 11, including 5 Richter's syndromes), secondary malignancies (n = 6), infections (n = 3), cardiac failure (n = 3), severe bleeding (n = 2), and sudden death (n = 1). In conclusion, our analyses confirmed the overall effectiveness and favorable safety profile of the ibrutinib-single agent therapeutic approach in CLL patients ≥80 years.

Unselected donor-derived hematopoietic stem cells boost for Chimeric Antigen Receptor T-cell associated hematotoxicity.

Hematological toxicity following Chimeric Antigen Receptor-T therapy in a patient with a prior allogeneic stem cell transplantation was resolved by the infusion of unselected donor-derived stem cell boost. Due to the donor's lymphocytes, the patient experienced a well-controlled flare-up of acute graft versus host disease.

Endothelial activation predicts disseminated intravascular coagulopathy, cytokine release syndrome and prognosis in patients treated with anti-CD19 CAR-T cells.

Cytokine release syndrome (CRS) and consumptive coagulopathy can complicate the treatment with chimeric antigen receptor T (CAR-T) cells. The modified version of the Endothelial Activation and Stress Index (mEASIX), a score derived from haematopoietic stem cell transplantation, combines platelets, C-reactive protein (CRP), and lactate dehydrogenase (LDH) and has been correlated with CRS and endothelial biomarkers. In 38 consecutive patients with aggressive lymphoproliferative disease we measured a coagulative laboratory panel at baseline and early after infusion of anti-CD19 CAR-T. The panel was investigated also in the presence of CRS graded 2 or higher, or immune effector cell-associated neurotoxicity syndrome (ICANS). Moreover, we examined the relationship between mEASIX, coagulation biomarkers, and toxicities of CAR-T cells. During CRS grade 2 or higher, we found increased prothrombin time (PT) and activated partial thromboplastin time (aPTT), fibrinogen, D-dimer, factor VIII (FVIII), and von Willebrand factor (vWF) antigen levels, and decreased platelet count and antithrombin levels. The occurrence of immune effector cell-associated neurotoxicity syndrome was associated with higher PT values, D-dimer, FVIII, and vWF levels, and decreased fibrinogen levels and platelet count. A higher mEASIX score correlated with increased aPTT values, fibrinogen, D-dimer, FVIII and vWF levels, and decreased antithrombin levels. Baseline mEASIX was predictive for consumptive coagulopathy and CRS graded 2 or higher, and for progression-free survival and overall survival.

B-cell receptor signaling and genetic lesions in TP53 and CDKN2A/CDKN2B cooperate in Richter transformation.

B-cell receptor (BCR) signals play a critical role in the pathogenesis of chronic lymphocytic leukemia (CLL), but their role in regulating CLL cell proliferation has still not been firmly established. Unlike normal B cells, CLL cells do not proliferate in vitro upon engagement of the BCR, suggesting that CLL cell proliferation is regulated by other signals from the microenvironment, such as those provided by Toll-like receptors or T cells. Here, we report that BCR engagement of human and murine CLL cells induces several positive regulators of the cell cycle, but simultaneously induces the negative regulators CDKN1A, CDKN2A, and CDKN2B, which block cell-cycle progression. We further show that introduction of genetic lesions that downregulate these cell-cycle inhibitors, such as inactivating lesions in CDKN2A, CDKN2B, and the CDKN1A regulator TP53, leads to more aggressive disease in a murine in vivo CLL model and spontaneous proliferation in vitro that is BCR dependent but independent of costimulatory signals. Importantly, inactivating lesions in CDKN2A, CDKN2B, and TP53 frequently co-occur in Richter syndrome (RS), and BCR stimulation of human RS cells with such lesions is sufficient to induce proliferation. We also show that tumor cells with combined TP53 and CDKN2A/2B abnormalities remain sensitive to BCR-inhibitor treatment and are synergistically sensitive to the combination of a BCR and cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor both in vitro and in vivo. These data provide evidence that BCR signals are directly involved in driving CLL cell proliferation and reveal a novel mechanism of Richter transformation.

Preexisting and treatment-emergent autoimmune cytopenias in patients with CLL treated with targeted drugs.

Autoimmune cytopenias (AICs) affect 5% to 9% of patients with chronic lymphocytic leukemia (CLL). Targeted drugs-ibrutinib, idelalisib, and venetoclax-have a prominent role in the treatment of CLL, but their impact on CLL-associated AICs is largely unknown. In this study, we evaluated the characteristics and outcome of preexisting AICs and described the incidence, quality, and management of treatment-emergent AICs during therapy with targeted drugs in patients with CLL. We collected data from 572 patients treated with ibrutinib (9% in combination with an anti-CD20 monoclonal antibody), 143 treated with idelalisib-rituximab, and 100 treated with venetoclax (12% in combination with an anti-CD20 monoclonal antibody). A history of preexisting AICs was reported in 104 (13%) of 815 patients. Interestingly, 80% of patients whose AICs had not resolved when treatment with a targeted drug was started experienced an improvement or a resolution during therapy. Treatment-emergent AICs occurred in 1% of patients during ibrutinib therapy, in 0.9% during idelalisib therapy, and in 7% during venetoclax therapy, with an estimated incidence rate of 5, 6, and 69 episodes per 1000 patients per year of exposure in the 3 treatment groups, respectively. The vast majority of patients who developed treatment-emergent AICs had unfavorable biological features such as an unmutated IGHV and a del(17p) and/or TP53 mutation. Notably, despite AICs, 83% of patients were able to continue the targeted drug, in some cases in combination with additional immunosuppressive agents. Overall, treatment with ibrutinib, idelalisib, or venetoclax seems to have a beneficial impact on CLL-associated AICs, inducing an improvement or even a resolution of preexisting AICs in most cases and eliciting treatment-emergent AICs in a negligible portion of patients.

The immunomodulatory molecule TIGIT is expressed by chronic lymphocytic leukemia cells and contributes to anergy.

T-cell immunoreceptor with Ig and ITIM domains (TIGIT) is an inhibitory checkpoint receptor that negatively regulates Tcell responses. CD226 competes with TIGIT for binding to the CD155 ligand, delivering a positive signal to the T cell. Here we studied the expression of TIGIT and CD226 in a cohort of 115 patients with chronic lymphocytic leukemia (CLL) and report expression of TIGIT and CD226 by leukemic cells. By devising a TIGIT/CD226 ratio, we showed that CLL cells favoring TIGIT over CD226 are typical of a more indolent disease, while those favoring CD226 are characterized by a shorter time to first treatment and shorter progression-free survival after first treatment. TIGIT expression was inversely correlated to the B-cell receptor (BCR) signaling capacity, as determined by studying BTK phosphorylation, cell proliferation and interleukin- 10 production. In CLL cells treated with ibrutinib, in which surface IgM and BCR signaling capacity are temporarily increased, TIGIT expression was downmodulated, in line with data indicating transient recovery from anergy. Lastly, cells from patients with Richter syndrome were characterized by high levels of CD226, with low to undetectable TIGIT, in keeping with their high proliferative drive. Together, these data suggest that TIGIT contributes to CLL anergy by downregulating BCR signaling, identifying novel and actionable molecular circuits regulating anergy and modulating CLL cell functions.

High rate of durable responses with undetectable minimal residual disease with front-line venetoclax and rituximab in young, fit patients with chronic lymphocytic leukemia and an adverse biological profile: results of the GIMEMA phase II LLC1518 - VERITAS study.

The GIMEMA phase II LLC1518 VERITAS trial investigated the efficacy and safety of front-line, fixed-duration venetoclax and rituximab (VenR) in combination in young (≤65 years), fit patients with chronic lymphocytic leukemia and unmutated IGHV and/or TP53 disruption. Treatment consisted of the venetoclax ramp-up, six monthly courses of the VenR combination, followed by six monthly courses of venetoclax as a single agent. A centralized assessment of minimal residual disease (MRD) was performed by allele-specific oligonucleotide polymerase chain reaction assay on the peripheral blood and bone marrow at the end of treatment (EOT) and during the follow-up. The primary endpoint was the complete remission rate at the EOT. Seventy-five patients were enrolled; the median age was 54 years (range, 38-65), 96% had unmutated IGHV, 12% had TP53 disruption, and 4% had mutated IGHV with TP53 disruption. The overall response rate at the EOT was 94.7%, with a complete remission rate of 76%. MRD was undetectable in the peripheral blood of 69.3% of patients and in the bone marrow of 58.7% of patients. The 12-month MRD-free survival in the 52 patients with undetectable MRD in the peripheral blood at the EOT was 73.1%. After a median follow-up of 20.8 months, no cases of disease progression were observed. Three patients had died, two due to COVID-19 and one due to tumor lysis syndrome. The first report of the VERITAS study shows that front-line VenR was associated with a high rate of complete remissions and durable response with undetectable MRD in young patients with chronic lymphocytic leukemia and unfavorable genetic characteristics. ClinicalTrials.gov identifier: NCT03455517.

Richter transformation in Chronic Lymphocytic Leukemia.

Chronic lymphocytic leukemia can evolve to an aggressive lymphoma-in most of the cases diffuse large B cells lymphoma, rarely Hodgkin lymphoma-and this complication is defined Richter syndrome (RS). Immunogenotypic features that characterize RS include unmutated IgHV status with high prevalence of IgHV4-39/D6-13/J5 sequence; deletion of chromosome 17p or 11q; activation of oncogenes as NOTCH1 and c-MYC; inactivation of onco-suppressors as TP53 and CDKN2A; high expression of CD38 in lymph-nodes. The prognosis of this condition is very poor: patients experience a rapid clinical deterioration with frequent therapeutic failure since the current options include suboptimal strategies as standard chemo-immunotherapy followed by hematopoietic stem cells transplantation or enrollment in clinical trials which investigate the efficacy of target drugs. Understanding the biology of such a heterogeneous condition is crucial to personalize the treatment and improve patient's survival.

Real-world evidence on venetoclax in chronic lymphocytic leukemia: The Italian experience.

Chronic lymphocytic leukemia (CLL) is the most common form of adult leukemia in the western world. In Italy, venetoclax was approved for use in patients with CLL as monotherapy in 2017 and in combinations in 2019. As a result of this delayed approval, there are relatively few real-world studies from Italian clinical practice and much of the data are in heavily pretreated patients. We have collected the available studies in Italian routine practice. Three studies confirm the effectiveness and tolerability of this agent in patients with relapsed/refractory CLL and high-risk disease characteristics, many of whom had received prior B-cell receptor signaling treatment. Addition of rituximab to venetoclax produced more complete responses in patients with relapsed/refractory CLL, while higher disease burden and progression while receiving a prior Bruton's tyrosine kinase inhibitor were both associated with poorer outcomes in patients treated with venetoclax. Venetoclax was well-tolerated with low discontinuation rates. No studies of venetoclax plus obinutuzumab for the first-line treatment of patients with CLL were available due to the short time since approval in Italy. Several cohorts addressed the impact of COVID-19 on patient management and outcomes, suggesting that treated patients and those in clinical observation had similar rates of COVID-19-related hospital admission, intensive care unit admission, and mortality. Overall, the responses and tolerance to venetoclax observed in the Italian real-world setting confirm the tolerability and effectiveness of venetoclax regimens in high-risk patients.

Correspondence in reference to the previously published manuscript: Reduction of cycles of bendamustine plus rituximab therapy in the cases with good response for indolent B-cell lymphomas.

Takezaki et al. analyzed the outcome of 57 patients with indolent lymphomas treated with Bendamustine plus Rituximab (BR) according to the number of cycles received, showing that patients who discontinued BR after four cycles had similar outcomes compared to patients who received five or six cycles. Considering the similarities but also the differences between indolent lymphomas and chronic lymphocytic leukemia (CLL), we enriched the results obtained with a cohort of CLL patients treated with BR starting from the experience of the Lazio region group on CLL. Out of 115 patients, 97 (84%) received 4-6 cycles of BR, while 18 (16%) received 1-3 cycles. The outcome of the group of patients who received at least 4 cycles was superior in terms of response rate (ORR 96% vs. ORR 83%, p = 0.041; CR 58% vs. CR 28%, p = 0.052 respectively) and PFS [median PFS 52.6 (40.3-64.9) versus 26.2 (19.3-33.0) months, p < 0.001]. The number of patients undergoing 4 cycles of BR (4-cycles group) and 5-6 cycles (over-4-cycles group) was 9 and 88, respectively. Compared to analysis conducted by the Japanese group in indolent lymphomas, in CLL we did not observe any difference between the outcome of the 4-cycles group and the over-4-cycles group in terms of ORR (89% vs. 97%, p = 0.268) and in survival [median PFS 40.8 (13.7-67.8) versus 52.6 (38.7-66.5) months, p = 0.117]. Moreover, we observed that patients who achieved a clinical CR showed overlapping outcomes with patients who received more than 4 cycles [CR vs. non-CR median PFS not reached vs. 11.0 months; over-4-cycles group median PFS 52.6 months (40.3-64.9); p < 0.001]. Nowadays chemoimmunotherapy with BR is reserved to fit elderly CLL patients, and there are many chemo-free treatment options available; therefore, discontinuation after 4 cycles may be permissible in patients who obtained a CR in order to limit toxicity as much as possible.

Lymphadenopathy as a predictor of progression during venetoclax treatment in chronic lymphocytic leukemia. A campus chronic lymphocytic leukemia study.

Clinical or biological parameters useful to predict progression during treatment in real-life setting with ibrutinib, idelalisib and venetoclax in relapsed/refractory chronic lymphocytic leukemia (CLL) are still debated. We conducted a multi-center retrospective study on CLL patients treated with ibrutinib and/or idelalisib who were switched to venetoclax for progression or due to adverse events to identify any clinical and/or biological parameters useful to predict progression during treatment with venetoclax. Of all the 128 evaluable patients, 81 had received ibrutinib prior to switching to venetoclax, 35 had received idelalisib and 12 both. When comparing the three subgroups, we did not notice any statistical difference in terms of clinical or biological features. No variable at baseline and at different time points during the follow-up (at 6, 12, 18 and 24 months) was found to predict progression nor to have significance for Progression Free Survival (PFS) in the ibrutinib group and in the idelalisib group and in subgroups according to the line of treatment. Analyzing the data of the venetoclax treatment, after a median follow up of 14.3 months, median PFS was not reached and estimated 3-year PFS was 54%. Of the 128 patients treated with venetoclax, 28 (22%) experienced progressive disease. At multivariate analysis for predictive factors for progression, lymph node diameter >56.5 mm before starting treatment emerged as an independent risk factor for progression. The lymph node predictive role for progression during venetoclax treatment could be a new parameter that deserves to be investigate in future studies.

Role of microRNAs in Chronic Lymphocytic Leukemia.

Chronic Lymphocytic Leukemia (CLL) is the most common form of leukemia in adults, with a highly variable clinical course. Improvement in the knowledge of the molecular pathways behind this disease has led to the development of increasingly specific therapies, such as BCR signaling inhibitors and BCL-2 inhibitors. In this context, the emerging role of microRNAs (miRNAs) in CLL pathophysiology and their possible application in therapy is worth noting. MiRNAs are one of the most important regulatory molecules of gene expression. In CLL, they can act both as oncogenes and tumor suppressor genes, and the deregulation of specific miRNAs has been associated with prognosis, progression, and drug resistance. In this review, we describe the role of the miRNAs that primarily impact the disease, and how these miRNAs could be used as therapeutic tools. Certainly, the use of miRNAs in clinical practice is still limited in CLL. Many issues still need to be solved, particularly regarding their biological and safety profile, even if several studies have suggested their efficacy on the disease, alone or in combination with other drugs.

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.

CD49d promotes disease progression in chronic lymphocytic leukemia: new insights from CD49d bimodal expression.

CD49d is a remarkable prognostic biomarker of chronic lymphocytic leukemia (CLL). The cutoff value for the extensively validated 30% of positive CLL cells is able to separate CLL patients into 2 subgroups with different prognoses, but it does not consider the pattern of CD49d expression. In the present study, we analyzed a cohort of 1630 CLL samples and identified the presence of ∼20% of CLL cases (n = 313) characterized by a bimodal expression of CD49d, that is, concomitant presence of a CD49d+ subpopulation and a CD49d- subpopulation. At variance with the highly stable CD49d expression observed in CLL patients with a homogeneous pattern of CD49d expression, CD49d bimodal CLL showed a higher level of variability in sequential samples, and an increase in the CD49d+ subpopulation over time after therapy. The CD49d+ subpopulation from CD49d bimodal CLL displayed higher levels of proliferation compared with the CD49d- cells; and was more highly represented in the bone marrow compared with peripheral blood (PB), and in PB CLL subsets expressing the CXCR4dim/CD5bright phenotype, known to be enriched in proliferative cells. From a clinical standpoint, CLL patients with CD49d bimodal expression, regardless of whether the CD49d+ subpopulation exceeded the 30% cutoff or not, experienced clinical behavior similar to CD49d+ CLL, both in chemoimmunotherapy (n = 1522) and in ibrutinib (n = 158) settings. Altogether, these results suggest that CD49d can drive disease progression in CLL, and that the pattern of CD49d expression should also be considered to improve the prognostic impact of this biomarker in CLL.

Use of BTK inhibitors with special focus on ibrutinib in Waldenström macroglobulinemia: An expert panel opinion statement.

The pivotal role that ibrutinib plays in the management of Waldenström macroglobulinemia (WM) is undisputed but there are ongoing questions regarding its positioning in the therapeutic algorithm of WM as well as in some peculiar clinical situations. A panel of experts from Italy was convened to provide real world recommendations on the use of BTK inhibitors in lymphoproliferative diseases in general, and in patients with WM in particular. This position paper represents the panel's collective analysis, evaluation, and opinions and is made up of a series of questions frequently asked by practicing clinicians and answers based on currently available evidence.

Use of BTK inhibitors with focus on ibrutinib in mantle cell lymphoma: An expert panel opinion statement.

The introduction of Bruton's tyrosine kinase (BTK) inhibitors transformed the management of patients with mantle cell lymphoma (MCL). Ibrutinib, the first-in-class BTK inhibitor is now approved in more than 80 countries and there are over 20 new BTK inhibitors in development. In addition, novel agents show potential clinical activity (alone and in combination) and are in the approval phase and/or being studied in ongoing clinical trials. How does the practicing clinician decide on the optimal therapeutic strategy for this highly heterogenous disease? In July 2020 a group of experts from Italy, convened a meeting to address and provide clarification on a series of outstanding issues in the treatment of MCL with the view of providing clinical guidance on its management. This expert opinion statement represents the panel's collective analysis, evaluation, and recommendations and is made up of a series of questions and answers (in the form of a review of the pertinent literature) designed to replicate those posed by practicing clinicians in Italy but which are applicable to clinical settings worldwide.