Interleukin-10 receptor signaling promotes the maintenance of a PD-1int TCF-1+ CD8+ T cell population that sustains anti-tumor immunity.

T cell exhaustion limits anti-tumor immunity and responses to immunotherapy. Here, we explored the microenvironmental signals regulating T cell exhaustion using a model of chronic lymphocytic leukemia (CLL). Single-cell analyses identified a subset of PD-1hi, functionally impaired CD8+ T cells that accumulated in secondary lymphoid organs during disease progression and a functionally competent PD-1int subset. Frequencies of PD-1int TCF-1+ CD8+ T cells decreased upon Il10rb or Stat3 deletion, leading to accumulation of PD-1hi cells and accelerated tumor progression. Mechanistically, inhibition of IL-10R signaling altered chromatin accessibility and disrupted cooperativity between the transcription factors NFAT and AP-1, promoting a distinct NFAT-associated program. Low IL10 expression or loss of IL-10R-STAT3 signaling correlated with increased frequencies of exhausted CD8+ T cells and poor survival in CLL and in breast cancer patients. Thus, balance between PD-1hi, exhausted CD8+ T cells and functional PD-1int TCF-1+ CD8+ T cells is regulated by cell-intrinsic IL-10R signaling, with implications for immunotherapy.

First-Line Venetoclax Combinations in Chronic Lymphocytic Leukemia.

BACKGROUND: Randomized trials of venetoclax plus anti-CD20 antibodies as first-line treatment in fit patients (i.e., those with a low burden of coexisting conditions) with advanced chronic lymphocytic leukemia (CLL) have been lacking. METHODS: In a phase 3, open-label trial, we randomly assigned, in a 1:1:1:1 ratio, fit patients with CLL who did not have TP53 aberrations to receive six cycles of chemoimmunotherapy (fludarabine-cyclophosphamide-rituximab or bendamustine-rituximab) or 12 cycles of venetoclax-rituximab, venetoclax-obinutuzumab, or venetoclax-obinutuzumab-ibrutinib. Ibrutinib was discontinued after two consecutive measurements of undetectable minimal residual disease or could be extended. The primary end points were undetectable minimal residual disease (sensitivity, <10-4 [i.e., <1 CLL cell in 10,000 leukocytes]) as assessed by flow cytometry in peripheral blood at month 15 and progression-free survival. RESULTS: A total of 926 patients were assigned to one of the four treatment regimens (229 to chemoimmunotherapy, 237 to venetoclax-rituximab, 229 to venetoclax-obinutuzumab, and 231 to venetoclax-obinutuzumab-ibrutinib). At month 15, the percentage of patients with undetectable minimal residual disease was significantly higher in the venetoclax-obinutuzumab group (86.5%; 97.5% confidence interval [CI], 80.6 to 91.1) and the venetoclax-obinutuzumab-ibrutinib group (92.2%; 97.5% CI, 87.3 to 95.7) than in the chemoimmunotherapy group (52.0%; 97.5% CI, 44.4 to 59.5; P<0.001 for both comparisons), but it was not significantly higher in the venetoclax-rituximab group (57.0%; 97.5% CI, 49.5 to 64.2; P = 0.32). Three-year progression-free survival was 90.5% in the venetoclax-obinutuzumab-ibrutinib group and 75.5% in the chemoimmunotherapy group (hazard ratio for disease progression or death, 0.32; 97.5% CI, 0.19 to 0.54; P<0.001). Progression-free survival at 3 years was also higher with venetoclax-obinutuzumab (87.7%; hazard ratio for disease progression or death, 0.42; 97.5% CI, 0.26 to 0.68; P<0.001), but not with venetoclax-rituximab (80.8%; hazard ratio, 0.79; 97.5% CI, 0.53 to 1.18; P = 0.18). Grade 3 and grade 4 infections were more common with chemoimmunotherapy (18.5%) and venetoclax-obinutuzumab-ibrutinib (21.2%) than with venetoclax-rituximab (10.5%) or venetoclax-obinutuzumab (13.2%). CONCLUSIONS: Venetoclax-obinutuzumab with or without ibrutinib was superior to chemoimmunotherapy as first-line treatment in fit patients with CLL. (Funded by AbbVie and others; GAIA-CLL13 ClinicalTrials.gov number, NCT02950051; EudraCT number, 2015-004936-36.).

Nucleosome repositioning in chronic lymphocytic leukemia.

The location of nucleosomes in the human genome determines the primary chromatin structure and regulates access to regulatory regions. However, genome-wide information on deregulated nucleosome occupancy and its implications in primary cancer cells is scarce. Here, we conducted a genome-wide comparison of high-resolution nucleosome maps in peripheral blood B cells from patients with chronic lymphocytic leukemia (CLL) and healthy individuals at single-base-pair resolution. Our investigation uncovered significant changes of nucleosome positioning in CLL. Globally, the spacing between nucleosomes-the nucleosome repeat length (NRL)-is shortened in CLL. This effect is stronger in the more aggressive IGHV-unmutated CLL subtype than in the IGHV-mutated CLL subtype. Changes in nucleosome occupancy at specific sites are linked to active chromatin remodeling and reduced DNA methylation. Nucleosomes lost or gained in CLL marks differential binding of 3D chromatin organizers such as CTCF as well as immune response-related transcription factors and delineated mechanisms of epigenetic deregulation. The principal component analysis of nucleosome occupancy in cancer-specific regions allowed the classification of samples between cancer subtypes and normal controls. Furthermore, patients could be better assigned to CLL subtypes according to differential nucleosome occupancy than based on DNA methylation or gene expression. Thus, nucleosome positioning constitutes a novel readout to dissect molecular mechanisms of disease progression and to stratify patients. Furthermore, we anticipate that the global nucleosome repositioning detected in our study, such as changes in the NRL, can be exploited for liquid biopsy applications based on cell-free DNA to stratify patients and monitor disease progression.

Acalabrutinib, venetoclax, and obinutuzumab in relapsed/refractory CLL: final efficacy and ctDNA analysis of the CLL2-BAAG trial.

ABSTRACT: The phase 2 CLL2-BAAG trial tested the measurable residual disease (MRD)-guided triple combination of acalabrutinib, venetoclax, and obinutuzumab after optional bendamustine debulking in 45 patients with relapsed/refractory chronic lymphocytic leukemia (CLL). MRD was measured by flow cytometry (FCM; undetectable MRD <10-4) in peripheral blood (PB) and circulating tumor DNA (ctDNA) using digital droplet polymerase chain reaction of variable-diversity-joining (VDJ) rearrangements and CLL-related mutations in plasma. The median number of previous treatments was 1 (range, 1-4); 18 patients (40%) had received a Bruton tyrosine kinase inhibitor (BTKi) and/or venetoclax before inclusion, 14 of 44 (31.8%) had TP53 aberrations, and 34 (75.6%) had unmutated immunoglobulin heavy-chain variable region genes. With a median observation time of 36.3 months and all patients off-treatment for a median of 21.9 months, uMRD <10-4 in PB was achieved in 42 of the 45 patients (93.3%) at any time point, including 17 of 18 (94.4%) previously exposed to venetoclax/BTKi and 13 of 14 (92.9%) with TP53 aberrations. The estimated 3-year progression-free and overall survival rates were 85.0% and 93.8%, respectively. Overall, 585 paired FCM/ctDNA samples were analyzed and 18 MRD recurrences (5 with and 13 without clinical progression) occurred after the end of treatment. Twelve samples were first detected by ctDNA, 3 by FCM, and 3 synchronously. In conclusion, time-limited MRD-guided acalabrutinib, venetoclax, and obinutuzumab achieved deep remissions in almost all patients with relapsed/refractory CLL. The addition of ctDNA-based analyses to FCM MRD assessment seems to improve early detection of relapses. This trial was registered at www.clinicaltrials.gov as #NCT03787264.

Reassessing the chronic lymphocytic leukemia International Prognostic Index in the era of targeted therapies.

ABSTRACT: We evaluated the chronic lymphocytic leukemia International Prognostic Index (CLL-IPI) in patients with CLL treated first line with targeted drugs (n = 991) or chemoimmunotherapy (n = 1256). With a median observation time of 40.5 months, the 3-year progression-free survival (PFS) rates for targeted drug-treated patients varied by CLL-IPI risk group: 96.5% (low), 87.6% (intermediate), 82.4% (high), and 78.7% (very high). Differences between consecutive CLL-IPI risk groups were observed for intermediate vs low and high vs intermediate, but not very high vs high. CLL-IPI factors ß2-microglobulin, immunoglobulin heavy variable (IGHV) status, and TP53 status each retained prognostic value for PFS. The 3-year overall survival (OS) rates by CLL-IPI risk groups were 100%, 96%, 93.9%, and 89.4%, respectively, with no differences between consecutive risk groups. Age, Binet stage, ß2-microglobulin, and TP53 status each retained prognostic value for OS. In chemoimmunotherapy patients (median observation time, 66.9 months), 3-year PFS rates for CLL-IPI risk groups were 78.1%, 51.4%, 40.1%, and 16.5%, respectively; corresponding 3-year OS rates were 97.4%, 93.1%, 81.8%, and 57.3%. In a matched-pair analysis, PFS differences in targeted therapies (n = 812) vs chemoimmunotherapy (n = 812) across all risk groups and OS differences in all but patients at low risk were demonstrated. The CLL-IPI maintains its prognostic value in predicting PFS outcomes with targeted drugs, but its impact in predicting survival appears diminished. Targeted therapies showed enhanced outcomes over chemoimmunotherapy, highlighting their effectiveness across various risk groups. Our findings support ongoing assessment of prognostic tools in CLL treatment evolution. These trials were registered at www.ClinicalTrials.gov as #NCT02345863, #NCT02401503, #NCT02689141, #NCT02445131, #NCT02758665, #NCT02950051, #NCT02242942, #NCT00262782, #NCT00281918, and #NCT01010061.

T-bet suppresses proliferation of malignant B cells in chronic lymphocytic leukemia.

The T-box transcription factor T-bet is known as a master regulator of T-cell response but its role in malignant B cells is not sufficiently explored. Here, we conducted single-cell resolved multi-omics analyses of malignant B cells from patients with chronic lymphocytic leukemia (CLL) and studied a CLL mouse model with genetic knockout of TBX21. We found that T-bet acts as a tumor suppressor in malignant B cells by decreasing their proliferation rate. NF-κB activity induced by inflammatory signals provided by the microenvironment, triggered T-bet expression which impacted on promoter proximal and distal chromatin co-accessibility and controlled a specific gene signature by mainly suppressing transcription. Gene set enrichment analysis identified a positive regulation of interferon signaling, and a negative control of proliferation by T-bet. In line, we showed that T-bet represses cell cycling and is associated with longer overall survival of CLL patients. Our study uncovers a novel tumor suppressive role of T-bet in malignant B cells via its regulation of inflammatory processes and cell cycling which has implications for stratification and therapy of CLL patients. Linking T-bet activity to inflammation explains the good prognostic role of genetic alterations in inflammatory signaling pathways in CLL.

Ibrutinib combined with immunochemotherapy with or without autologous stem-cell transplantation versus immunochemotherapy and autologous stem-cell transplantation in previously untreated patients with mantle cell lymphoma (TRIANGLE): a three-arm, randomised, open-label, phase 3 superiority trial of the European Mantle Cell Lymphoma Network.

BACKGROUND: Adding ibrutinib to standard immunochemotherapy might improve outcomes and challenge autologous stem-cell transplantation (ASCT) in younger (aged 65 years or younger) mantle cell lymphoma patients. This trial aimed to investigate whether the addition of ibrutinib results in a superior clinical outcome compared with the pre-trial immunochemotherapy standard with ASCT or an ibrutinib-containing treatment without ASCT. We also investigated whether standard treatment with ASCT is superior to a treatment adding ibrutinib but without ASCT. METHODS: The open-label, randomised, three-arm, parallel-group, superiority TRIANGLE trial was performed in 165 secondary or tertiary clinical centres in 13 European countries and Israel. Patients with previously untreated, stage II-IV mantle cell lymphoma, aged 18-65 years and suitable for ASCT were randomly assigned 1:1:1 to control group A or experimental groups A+I or I, stratified by study group and mantle cell lymphoma international prognostic index risk groups. Treatment in group A consisted of six alternating cycles of R-CHOP (intravenous rituximab 375 mg/m2 on day 0 or 1, intravenous cyclophosphamide 750 mg/m2 on day 1, intravenous doxorubicin 50 mg/m2 on day 1, intravenous vincristine 1·4 mg/m2 on day 1, and oral prednisone 100 mg on days 1-5) and R-DHAP (or R-DHAOx, intravenous rituximab 375 mg/m2 on day 0 or 1, intravenous or oral dexamethasone 40 mg on days 1-4, intravenous cytarabine 2 × 2 g/m2 for 3 h every 12 h on day 2, and intravenous cisplatin 100 mg/m2 over 24 h on day 1 or alternatively intravenous oxaliplatin 130 mg/m2 on day 1) followed by ASCT. In group A+I, ibrutinib (560 mg orally each day) was added on days 1-19 of R-CHOP cycles and as fixed-duration maintenance (560 mg orally each day for 2 years) after ASCT. In group I, ibrutinib was given the same way as in group A+I, but ASCT was omitted. Three pairwise one-sided log-rank tests for the primary outcome of failure-free survival were statistically monitored. The primary analysis was done by intention-to-treat. Adverse events were evaluated by treatment period among patients who started the respective treatment. This ongoing trial is registered with ClinicalTrials.gov, NCT02858258. FINDINGS: Between July 29, 2016 and Dec 28, 2020, 870 patients (662 men, 208 women) were randomly assigned to group A (n=288), group A+I (n=292), and group I (n=290). After 31 months median follow-up, group A+I was superior to group A with 3-year failure-free survival of 88% (95% CI 84-92) versus 72% (67-79; hazard ratio 0·52 [one-sided 98·3% CI 0-0·86]; one-sided p=0·0008). Superiority of group A over group I was not shown with 3-year failure-free survival 72% (67-79) versus 86% (82-91; hazard ratio 1·77 [one-sided 98·3% CI 0-3·76]; one-sided p=0·9979). The comparison of group A+I versus group I is ongoing. There were no relevant differences in grade 3-5 adverse events during induction or ASCT between patients treated with R-CHOP/R-DHAP or ibrutinib combined with R-CHOP/R-DHAP. During maintenance or follow-up, substantially more grade 3-5 haematological adverse events and infections were reported after ASCT plus ibrutinib (group A+I; haematological: 114 [50%] of 231 patients; infections: 58 [25%] of 231; fatal infections: two [1%] of 231) compared with ibrutinib only (group I; haematological: 74 [28%] of 269; infections: 52 [19%] of 269; fatal infections: two [1%] of 269) or after ASCT (group A; haematological: 51 [21%] of 238; infections: 32 [13%] of 238; fatal infections: three [1%] of 238). INTERPRETATION: Adding ibrutinib to first-line treatment resulted in superior efficacy in younger mantle cell lymphoma patients with increased toxicity when given after ASCT. Adding ibrutinib during induction and as maintenance should be part of first-line treatment of younger mantle cell lymphoma patients. Whether ASCT adds to an ibrutinib-containing regimen is not yet determined. FUNDING: Janssen and Leukemia & Lymphoma Society.

The proto-oncogene TCL1A deregulates cell cycle and genomic stability in CLL.

Upregulation of the proto-oncogene T-cell leukemia/lymphoma 1A (TCL1A) is causally implicated in various B-cell and T-cell malignancies. High-level TCL1A correlates with aggressive disease features and inferior clinical outcomes. However, the molecular and cell biological consequences of, particularly nuclear, TCL1A are not fully elucidated. We observed here in mouse models of subcellular site-specific TCL1A-induced lymphomagenesis that TCL1A exerts a strong transforming impact via nuclear topography. In proteomic screens of TCL1A-bound molecules in chronic lymphocytic leukemia (CLL) cells and B-cell lymphoma lines, we identified regulators of cell cycle and DNA repair pathways as novel TCL1A interactors, particularly enriched under induced DNA damage and mitosis. By functional mapping and in silico modeling, we specifically identified the mitotic checkpoint protein, cell division cycle 20 (CDC20), as a direct TCL1A interactor. According to the regulatory impact of TCL1A on the activity of the CDC20-containing mitotic checkpoint and anaphase-promoting complexes during mitotic progression, TCL1A overexpression accelerated cell cycle transition in B-cell lymphoma lines, impaired apoptotic damage responses in association with pronounced chromosome missegregation, and caused cellular aneuploidy in Eµ-TCL1A mice. Among hematopoietic cancers, CDC20 levels seem particularly low in CLL. CDC20 expression negatively correlated with TCL1A and lower expression marked more aggressive and genomically instable disease and cellular phenotypes. Knockdown of Cdc20 in TCL1A-initiated murine CLL promoted aneuploidy and leukemic acceleration. Taken together, we discovered a novel cell cycle-associated effect of TCL1A abrogating controlled cell cycle transition. This adds to our concept of oncogenic TCL1A by targeting genome stability. Overall, we propose that TCL1A acts as a pleiotropic adapter molecule with a synergistic net effect of multiple hijacked pathways.

Detailed safety profile of acalabrutinib vs ibrutinib in previously treated chronic lymphocytic leukemia in the ELEVATE-RR trial.

ELEVATE-RR demonstrated noninferior progression-free survival and lower incidence of key adverse events (AEs) with acalabrutinib vs ibrutinib in previously treated chronic lymphocytic leukemia. We further characterize AEs of acalabrutinib and ibrutinib via post hoc analysis. Overall and exposure-adjusted incidence rate was assessed for common Bruton tyrosine kinase inhibitor-associated AEs and for selected events of clinical interest (ECIs). AE burden scores based on previously published methodology were calculated for AEs overall and selected ECIs. Safety analyses included 529 patients (acalabrutinib, n = 266; ibrutinib, n = 263). Among common AEs, incidences of any-grade diarrhea, arthralgia, urinary tract infection, back pain, muscle spasms, and dyspepsia were higher with ibrutinib, with 1.5- to 4.1-fold higher exposure-adjusted incidence rates. Incidences of headache and cough were higher with acalabrutinib, with 1.6- and 1.2-fold higher exposure-adjusted incidence rate, respectively. Among ECIs, incidences of any-grade atrial fibrillation/flutter, hypertension, and bleeding were higher with ibrutinib, as were exposure-adjusted incidence rates (2.0-, 2.8-, and 1.6-fold, respectively); incidences of cardiac events overall (the Medical Dictionary for Regulatory Activities system organ class) and infections were similar between arms. Rate of discontinuation because of AEs was lower for acalabrutinib (hazard ratio, 0.62; 95% confidence interval, 0.41-0.93). AE burden score was higher for ibrutinib vs acalabrutinib overall and for the ECIs atrial fibrillation/flutter, hypertension, and bleeding. A limitation of this analysis is its open-label study design, which may influence the reporting of more subjective AEs. Overall, event-based analyses and AE burden scores demonstrated higher AE burden overall and specifically for atrial fibrillation, hypertension, and hemorrhage with ibrutinib vs acalabrutinib. This trial was registered at www.clinicaltrials.gov as #NCT02477696.

Final analysis of the CLL2-GIVe trial: obinutuzumab, ibrutinib, and venetoclax for untreated CLL with del(17p)/TP53mut.

The final analysis of the open-label, multicenter phase 2 CLL2-GIVe trial shows response and tolerability of the triple combination of obinutuzumab, ibrutinib, and venetoclax (GIVe regimen) in 41 previously untreated patients with high-risk chronic lymphocytic leukemia (CLL) with del(17p) and/or TP53 mutation. Induction consisted of 6 cycles of GIVe; venetoclax and ibrutinib were continued up to cycle 12 as consolidation. Ibrutinib was given until cycle 15 or up to cycle 36 in patients not achieving a complete response and with detectable minimal residual disease. The primary end point was the complete remission rate at cycle 15, which was achieved at 58.5% (95% CI, 42.1-73.7; P < .001). The last patient reached the end of the study in January 2022. After a median observation time of 38.4 months (range, 3.7-44.9), the 36-month progression-free survival was 79.9%, and the 36-month overall survival was 92.6%. Only 6 patients continued ibrutinib maintenance. Adverse events of concern were neutropenia (48.8%, grade ≥3) and infections (19.5%, grade ≥3). Cardiovascular toxicity grade 3 occurred as atrial fibrillation at a rate of 2.4% between cycles 1 and 12, as well as hypertension (4.9%) between cycles 1 and 6. The incidence of adverse events of any grade and grade ≥3 was highest during induction and decreased over time. Progressive disease was observed in 7 patients between cycles 27 and 42. In conclusion, the CLL2-GIVe regimen is a promising fixed-duration, first-line treatment for patients with high-risk CLL with a manageable safety profile.

Oncogenic role and target properties of the lysine-specific demethylase KDM1A in chronic lymphocytic leukemia.

In chronic lymphocytic leukemia (CLL), epigenetic alterations are considered to centrally shape the transcriptional signatures that drive disease evolution and underlie its biological and clinical subsets. Characterizations of epigenetic regulators, particularly histone-modifying enzymes, are very rudimentary in CLL. In efforts to establish effectors of the CLL-associated oncogene T-cell leukemia 1A (TCL1A), we identified here the lysine-specific histone demethylase KDM1A to interact with the TCL1A protein in B cells in conjunction with an increased catalytic activity of KDM1A. We demonstrate that KDM1A is upregulated in malignant B cells. Elevated KDM1A and associated gene expression signatures correlated with aggressive disease features and adverse clinical outcomes in a large prospective CLL trial cohort. Genetic Kdm1a knockdown in Eµ-TCL1A mice reduced leukemic burden and prolonged animal survival, accompanied by upregulated p53 and proapoptotic pathways. Genetic KDM1A depletion also affected milieu components (T, stromal, and monocytic cells), resulting in significant reductions in their capacity to support CLL-cell survival and proliferation. Integrated analyses of differential global transcriptomes (RNA sequencing) and H3K4me3 marks (chromatin immunoprecipitation sequencing) in Eµ-TCL1A vs iKdm1aKD;Eµ-TCL1A mice (confirmed in human CLL) implicate KDM1A as an oncogenic transcriptional repressor in CLL which alters histone methylation patterns with pronounced effects on defined cell death and motility pathways. Finally, pharmacologic KDM1A inhibition altered H3K4/9 target methylation and revealed marked anti-B-cell leukemic synergisms. Overall, we established the pathogenic role and effector networks of KDM1A in CLL via tumor-cell intrinsic mechanisms and its impacts in cells of the microenvironment. Our data also provide rationales to further investigate therapeutic KDM1A targeting in CLL.

High karyotypic complexity is an independent prognostic factor in patients with CLL treated with venetoclax combinations.

Complex karyotypes have been associated with inferior outcomes in chronic lymphocytic leukemia (CLL) treated with chemoimmunotherapy (CIT), whereas their prognostic impact in the context of venetoclax-based treatments is still debated. In this prospective analysis on karyotype complexity in CLL, we evaluated the impact of complex (≥3 chromosomal aberrations [CAs], CKTs) and highly complex karyotypes (≥5 CAs; hCKTs) as well as specific aberrations in previously untreated patients without TP53 aberrations undergoing either CIT or time-limited venetoclax-based therapies in the phase 3 GAIA/CLL13 trial. Karyotype analyses were available for 895 of 926 patients (96.7%), of whom 153 (17%) had a CKT and 43 (5%) hCKT. In the CIT arm, CKT was associated with shorter progression-free survival (PFS) (hazard ratio [HR] 2.58; 95% confidence interval [95% CI], 1.54-4.32; P < .001) and overall survival (HR, 3.25; 95% CI, 1.03-10.26; P = .044). In the pooled venetoclax arms, a multivariable analysis identified hCKTs (HR, 1.96; 95% CI, 1.03-3.72; P = .041), but not CKTs, as independent adverse prognosticators for PFS. The presence of translocations (unbalanced and/or balanced) was also independently associated with shorter PFSs in the venetoclax arms. CIT led to the acquisition of additional CAs (mean CAs, 2.0-3.4; from baseline to CLL progression), whereas karyotype complexity remained stable after venetoclax-based treatments (2.0, both time points). This analysis establishes highly complex karyotypes and translocations as adverse prognostic factors in the context of venetoclax-based combination treatments. The findings of this study support the incorporation of karyotyping into the standard diagnostic workup of CLL, because it identifies patients at high risk of poor treatment outcomes and thereby improves prognostication. This trial was registered at www.clinicaltrials.gov as #NCT02950051.

First-line venetoclax combinations versus chemoimmunotherapy in fit patients with chronic lymphocytic leukaemia (GAIA/CLL13): 4-year follow-up from a multicentre, open-label, randomised, phase 3 trial.

BACKGROUND: In the primary analysis report of the GAIA/CLL13 trial, we found that venetoclax-obinutuzumab and venetoclax-obinutuzumab-ibrutinib improved undetectable measurable residual disease (MRD) rates and progression-free survival compared with chemoimmunotherapy in patients with previously untreated chronic lymphocytic leukaemia. However, to our knowledge, no data on direct comparisons of different venetoclax-based combinations are available. METHODS: GAIA/CLL13 is an open-label, randomised, phase 3 study conducted at 159 sites in ten countries in Europe and the Middle East. Eligible patients were aged 18 years or older, with a life expectancy of at least 6 months, an Eastern Cooperative Oncology group performance status of 0-2, a cumulative illness rating scale score of 6 or lower or a single score of 4 or lower, and no TP53 aberrations. Patients were randomly assigned (1:1:1:1), with a computer-generated list stratified by age, Binet stage, and regional study group, to either chemoimmunotherapy, venetoclax-rituximab, venetoclax-obinutuzumab, or venetoclax-obinutuzumab-ibrutinib. All treatments were administered in 28-day cycles. Patients in the chemoimmunotherapy group received six cycles of treatment, with patients older than 65 years receiving intravenous bendamustine (90 mg/m2, days 1-2), whereas patients aged 65 years or younger received intravenous fludarabine (25 mg/m2, days 1-3) and intravenous cyclophosphamide (250 mg/m2, days 1-3). Intravenous rituximab (375 mg/m2, day 1 of cycle 1; 500 mg/m2, day 1 of cycles 2-6) was added to chemotherapy. In the experimental groups, patients received daily venetoclax (400 mg orally) for ten cycles after a 5-week ramp-up phase starting on day 22 of cycle 1. In the venetoclax-rituximab group, intravenous rituximab (375 mg/m2, day 1 of cycle 1; 500 mg/m2, day 1 of cycles 2-6) was added. In the obinutuzumab-containing groups, obinutuzumab was added (cycle 1: 100 mg on day 1, 900 mg on day 2, and 1000 mg on days 8 and 15; cycles 2-6: 1000 mg on day 1). In the venetoclax-obinutuzumab-ibrutinib group, daily ibrutinib (420 mg orally, from day 1 of cycle 1) was added until undetectable MRD was reached in two consecutive measurements (3 months apart) or until cycle 36. The planned treatment duration was six cycles in the chemoimmunotherapy group, 12 cycles in the venetoclax-rituximab and the venetoclax-obinutuzumab group and between 12 and 36 cycles in the venetoclax-obinutuzumab-ibrutinib group. Coprimary endpoints were the undetectable MRD rate in peripheral blood at month 15 for the comparison of venetoclax-obinutuzumab versus standard chemoimmunotherapy and investigator-assessed progression-free survival for the comparison of venetoclax-obinutuzumab-ibrutinib versus standard chemoimmunotherapy, both analysed in the intention-to-treat population (ie, all patients randomly assigned to treatment) with a split α of 0·025 for each coprimary endpoint. Both coprimary endpoints have been reported elsewhere. Here we report a post-hoc exploratory analysis of updated progression-free survival results after a 4-year follow-up of our study population. Safety analyses included all patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT02950051, recruitment is complete, and all patients are off study treatment. FINDINGS: Between Dec 13, 2016, and Oct 13, 2019, 1080 patients were screened and 926 were randomly assigned to treatment (chemoimmunotherapy group n=229; venetoclax-rituximab group n=237; venetoclax-obinutuzumab group n=229; and venetoclax-obinutuzumab-ibrutinib group n=231); mean age 60·8 years (SD 10·2), 259 (28%) of 926 patients were female, and 667 (72%) were male (data on race and ethnicity are not reported). At data cutoff for this exploratory follow-up analysis (Jan 31, 2023; median follow-up 50·7 months [IQR 44·6-57·9]), patients in the venetoclax-obinutuzumab group had significantly longer progression-free survival than those in the chemoimmunotherapy group (hazard ratio [HR] 0·47 [97·5% CI 0·32-0·69], p<0·0001) and the venetoclax-rituximab group (0·57 [0·38-0·84], p=0·0011). The venetoclax-obinutuzumab-ibrutinib group also had a significantly longer progression-free survival than the chemoimmunotherapy group (0·30 [0·19-0·47]; p<0·0001) and the venetoclax-rituximab group (0·38 [0·24-0·59]; p<0·0001). There was no difference in progression-free survival between the venetoclax-obinutuzumab-ibrutinib and venetoclax-obinutuzumab groups (0·63 [0·39-1·02]; p=0·031), and the proportional hazards assumption was not met for the comparison between the venetoclax-rituximab group versus the chemoimmunotherapy group (log-rank p=0·10). The estimated 4-year progression-free survival rate was 85·5% (97·5% CI 79·9-91·1; 37 [16%] events) in the venetoclax-obinutuzumab-ibrutinib group, 81·8% (75·8-87·8; 55 [24%] events) in the venetoclax-obinutuzumab group, 70·1% (63·0-77·3; 84 [35%] events) in the venetoclax-rituximab group, and 62·0% (54·4-69·7; 90 [39%] events) in the chemoimmunotherapy group. The most common grade 3 or worse treatment-related adverse event was neutropenia (114 [53%] of 216 patients in the chemoimmunotherapy group, 109 [46%] of 237 in the venetoclax-rituximab group, 127 [56%] of 228 in the venetoclax-obinutuzumab group, and 112 [48%] of 231 in the venetoclax-obinutuzumab-ibrutinib group). Deaths determined to be associated with study treatment by the investigator occurred in three (1%) patients in the chemoimmunotherapy group (n=1 due to each of sepsis, metastatic squamous cell carcinoma, and Richter's syndrome), none in the venetoclax-rituximab and venetoclax-obinutuzumab groups, and four (2%) in the venetoclax-obinutuzumab-ibrutinib group (n=1 due to each of acute myeloid leukaemia, fungal encephalitis, small-cell lung cancer, and toxic leukoencephalopathy). INTERPRETATION: With more than 4 years of follow-up, venetoclax-obinutuzumab and venetoclax-obinutuzumab-ibrutinib significantly extended progression-free survival compared with both chemoimmunotherapy and venetoclax-rituximab in previously untreated, fit patients with chronic lymphocytic leukaemia, thereby supporting their use and further evaluation in this patient group, while still considering the higher toxicities observed with the triple combination. FUNDING: AbbVie, Janssen, and F Hoffmann-La Roche.

Obinutuzumab (GA-101), ibrutinib, and venetoclax (GIVe) frontline treatment for high-risk chronic lymphocytic leukemia.

Despite considerable treatment advances with targeted therapies for patients with chronic lymphocytic leukemia (CLL) deemed high-risk [del(17p) and/or TP53 mutation], the outcome is still inferior compared with other CLL patients. Combining multiple agents with distinct mechanisms of action may further improve outcomes. CLL2-GIVe is an open-label, multicenter trial which enrolled patients with previously untreated CLL with del(17p) and/or TP53 mutation. Patients received induction therapy with obinutuzumab (GA-101), ibrutinib, and venetoclax (GIVe) for cycles 1 through 6 and consolidation therapy with venetoclax and ibrutinib for cycles 7 through 12. Ibrutinib monotherapy was continued for cycles 13 through 36 in patients not reaching a complete response (CR) with serial undetectable minimal residual disease (uMRD) after consolidation. The primary endpoint was CR rate at cycle 15 (final restaging). Secondary endpoints included MRD, survival, and safety. All 41 patients enrolled between September 2016 and August 2018 received study treatment and were included in efficacy and safety populations. With a CR rate of 58.5% at cycle 15, the primary endpoint was met (95% CI: 42.1-73.7; P < .001). At final restaging, 78.0% of patients had uMRD in peripheral blood (PB); 65.9% of patients had uMRD in bone marrow (BM). Estimated progression-free survival (PFS) and overall survival (OS) rates at 24 months were both 95.1%. Adverse events were reported in all patients; most were low grade (grade ≥3: 23.9%). Two deaths were reported (cardiac failure and ovarian carcinoma), neither related to study treatment. The CLL2-GIVe treatment regimen has a manageable safety profile and is a first-line treatment of good efficacy for patients with high-risk CLL.

Evaluation of vecabrutinib as a model for noncovalent BTK/ITK inhibition for treatment of chronic lymphocytic leukemia.

Covalent Bruton tyrosine kinase (BTK) inhibitors, such as ibrutinib, have proven to be highly beneficial in the treatment of chronic lymphocytic leukemia (CLL). Interestingly, the off-target inhibition of IL-2-inducible T-cell kinase (ITK) by ibrutinib may also play a role in modulating the tumor microenvironment, potentially enhancing the treatment benefit. However, resistance to covalently binding BTK inhibitors can develop as the result of a mutation in cysteine 481 of BTK (C481S), which prevents irreversible binding of the drugs. In the present study we performed preclinical characterization of vecabrutinib, a next-generation noncovalent BTK inhibitor that has ITK-inhibitory properties similar to those of ibrutinib. Unlike ibrutinib and other covalent BTK inhibitors, vecabrutinib showed retention of the inhibitory effect on C481S BTK mutants in vitro, similar to that of wild-type BTK. In the murine Eµ-TCL1 adoptive transfer model, vecabrutinib reduced tumor burden and significantly improved survival. Vecabrutinib treatment led to a decrease in CD8+ effector and memory T-cell populations, whereas the naive populations were increased. Of importance, vecabrutinib treatment significantly reduced the frequency of regulatory CD4+ T cells in vivo. Unlike ibrutinib, vecabrutinib treatment showed minimal adverse impact on the activation and proliferation of isolated T cells. Lastly, combination treatment with vecabrutinib and venetoclax augmented treatment efficacy, significantly improved survival, and led to favorable reprogramming of the microenvironment in the murine Eµ-TCL1 model. Thus, noncovalent BTK/ITK inhibitors, such as vecabrutinib, may be efficacious in C481S BTK mutant CLL while preserving the T-cell immunomodulatory function of ibrutinib.

The CLL12 trial: ibrutinib vs placebo in treatment-naïve, early-stage chronic lymphocytic leukemia.

Observation is the current standard of care for patients with early-stage asymptomatic chronic lymphocytic leukemia (CLL), as chemotherapy-based interventions have failed to prolong survival. We hypothesized that early intervention with ibrutinib would be well tolerated and lead to superior disease control in a subgroup of early-stage patients with CLL. The phase 3, double-blind, placebo-controlled CLL12 trial randomly assigned asymptomatic, treatment-naïve Binet stage A CLL patients at increased risk of progression in a 1:1 ratio to receive ibrutinib (n = 182) or placebo (n = 181) at a dose of 420 mg daily. At a median follow-up of 31 months, the study met its primary endpoint by significantly improving event-free survival in the ibrutinib group (median, not reached vs 47.8 months; hazard ratio = 0.25; 95% confidence interval = 0.14-0.43, P < .0001). Compared with placebo, ibrutinib did not increase overall toxicity, yielding similar incidence and severity of adverse events (AEs). The most common serious AEs were atrial fibrillation, pneumonia, and rash in the ibrutinib group, and basal cell carcinoma, pneumonia, and myocardial infarction in the placebo group. Ibrutinib-associated risk for bleeding (33.5%) was decreased by prohibiting the use of oral anticoagulants through an amendment of the study protocol and by avoiding CYP3A4 drug-drug interactions. Ibrutinib confirms efficacy in CLL patients at an early stage with an increased risk of progression. However, the results do not justify changing the current standard of "watch and wait." This trial was registered at www.clinicaltrials.gov as #NCT02863718.

Fludarabine, cyclophosphamide, and rituximab as first-line treatment in patients with chronic lymphocytic leukemia: A long-term analysis of the German CLL Study Group (GCLLSG) registry.

Long-term data of chronic lymphocytic leukemia (CLL) patients with favorable risk who were treated with fludarabine, cyclophosphamide, and rituximab (FCR) within clinical trials show good efficacy. We here report long-term data collected within the GCLLSG registry. Altogether, 417 CLL patients who received first-line treatment with FCR were analyzed, of which 293 (70.3%) were treated outside of clinical trials. The median observation time from first-line was 95.8 (interquartile range 58.7-126.8) months. Focusing on data of 194 (46.5%) patients who received FCR first-line treatment after 2013 (start of data collection within GCLLSG registry), responses were documented in 85% of the patients, non-responses in 15%, and for 3.6% the assessment was missing. Median event-free survival (EFS, time until disease progression, subsequent treatment, or death) was 60.2 months with a 5-year EFS-rate of 50.6%. Patients with higher-risk disease, characterized by unmutated IGHV (N = 78), had a median EFS of 45.4 months with a 5-year EFS rate of 36.3%, while the median EFS was 77.5 months with a 5-year EFS rate of 60.3% in patients with mutated IGHV (N = 40). Median overall survival was not reached with a 5-year survival rate of 92.7%. In summary, first-line FCR was associated with long EFS, especially in patients exhibiting a mutated IGHV status.

Impairment of α-tubulin and F-actin interactions of GJB3 induces aneuploidy in urothelial cells and promotes bladder cancer cell invasion.

BACKGROUND: We have previously identified an unsuspected role for GJB3 showing that the deficiency of this connexin protein induces aneuploidy in human and murine cells and accelerates cell transformation as well as tumor formation in xenograft models. The molecular mechanisms by which loss of GJB3 leads to aneuploidy and cancer initiation and progression remain unsolved. METHODS: GJB3 expression levels were determined by RT-qPCR and Western blot. The consequences of GJB3 knockdown on genome instability were assessed by metaphase chromosome counting, multinucleation of cells, by micronuclei formation and by the determination of spindle orientation. Interactions of GJB3 with α-tubulin and F-actin was analyzed by immunoprecipitation and immunocytochemistry. Consequences of GJB3 deficiency on microtubule and actin dynamics were measured by live cell imaging and fluorescence recovery after photobleaching experiments, respectively. Immunohistochemistry was used to determine GJB3 levels on human and murine bladder cancer tissue sections. Bladder cancer in mice was chemically induced by BBN-treatment. RESULTS: We find that GJB3 is highly expressed in the ureter and bladder epithelium, but it is downregulated in invasive bladder cancer cell lines and during tumor progression in both human and mouse bladder cancer. Downregulation of GJB3 expression leads to aneuploidy and genomic instability in karyotypically stable urothelial cells and experimental modulation of GJB3 levels alters the migration and invasive capacity of bladder cancer cell lines. Importantly, GJB3 interacts both with α-tubulin and F-actin. The impairment of these interactions alters the dynamics of these cytoskeletal components and leads to defective spindle orientation. CONCLUSION: We conclude that deregulated microtubule and actin dynamics have an impact on proper chromosome separation and tumor cell invasion and migration. Consequently, these observations indicate a possible role for GJB3 in the onset and spreading of bladder cancer and demonstrate a molecular link between enhanced aneuploidy and invasive capacity cancer cells during tumor cell dissemination.

Loss of ORP3 induces aneuploidy and promotes bladder cancer cell invasion through deregulated microtubule and actin dynamics.

We have recently shown that loss of ORP3 leads to aneuploidy induction and promotes tumor formation. However, the specific mechanisms by which ORP3 contributes to ploidy-control and cancer initiation and progression is still unknown. Here, we report that ORP3 is highly expressed in ureter and bladder epithelium while its expression is downregulated in invasive bladder cancer cell lines and during tumor progression, both in human and in mouse bladder cancer. Moreover, we observed an increase in the incidence of N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN)-induced invasive bladder carcinoma in the tissue-specific Orp3 knockout mice. Experimental data demonstrate that ORP3 protein interacts with γ-tubulin at the centrosomes and with components of actin cytoskeleton. Altering the expression of ORP3 induces aneuploidy and genomic instability in telomerase-immortalized urothelial cells with a stable karyotype and influences the migration and invasive capacity of bladder cancer cell lines. These findings demonstrate a crucial role of ORP3 in ploidy-control and indicate that ORP3 is a bona fide tumor suppressor protein. Of note, the presented data indicate that ORP3 affects both cell invasion and migration as well as genome stability through interactions with cytoskeletal components, providing a molecular link between aneuploidy and cell invasion and migration, two crucial characteristics of metastatic cells.

Real-world experience among patients with relapsed/refractory mantle cell lymphoma after Bruton tyrosine kinase inhibitor failure in Europe: The SCHOLAR-2 retrospective chart review study.

Mantle cell lymphoma (MCL) after relapse is associated with poor prognosis. No standard of care exists and available evidence for treatments is limited, particularly in patients who fail Bruton tyrosine kinase inhibitor (BTKi) therapy. This multicentre retrospective chart review study, SCHOLAR-2, addresses this knowledge gap and reports on data collected from 240 patients with relapsed/refractory MCL in Europe who were treated with BTKi-based therapy between July 2012 and July 2018, and had experienced disease progression while on BTKi therapy or discontinued BTKi therapy due to intolerance. The median overall survival (OS) from initiation of first BTKi therapy was 14.6 months (95% confidence interval [CI] 11.6-20.0) in the overall cohort, 5.5 months (95% CI 3.9-8.2) in 91 patients without post-BTKi therapy, and 23.8 months (95% CI 18.9-30.1) in 149 patients who received post-BTKi therapy (excluding chimeric antigen receptor T-cell treatment). In the latter group, patients received a median of one (range, one to seven) line of post-BTKi therapy, with lenalidomide-containing regimens and bendamustine plus rituximab being the most frequently administered; the median OS from initiation of first post-BTKi therapy was 9.7 months (95% CI 6.3-12.7). These results provide a benchmark for survival in patients with R/R MCL receiving salvage therapy after BTKi failure.