Combination Of Ibrutinib Research Articles

Inhibition of Bruton's tyrosine kinase with PD-1 blockade modulates T cell activation in solid tumors.

BACKGROUNDInhibition of Bruton's tyrosine kinase with ibrutinib blocks the function of myeloid-derived suppressor cells (MDSC). The combination of ibrutinib and nivolumab was tested in patients with metastatic solid tumors.METHODSSixteen patients received ibrutinib 420 mg p.o. daily with nivolumab 240 mg i.v. on days 1 and 15 of a 28-day cycle. The effect of ibrutinib and nivolumab on MDSC, the immune profile, and cytokine levels were measured. Single-cell RNA-Seq and T cell receptor sequencing of immune cells was performed.RESULTSCommon adverse events were fatigue and anorexia. Four patients had partial responses and 4 had stable disease at 3 months (average 6.5 months, range 3.5-14.6). Median overall survival (OS) was 10.8 months. Seven days of Bruton's tyrosine kinase (BTK) inhibition significantly increased the proportion of monocytic-MDSC (M-MDSC) and significantly decreased chemokines associated with MDSC recruitment and accumulation (CCL2, CCL3, CCL4, CCL13). Single-cell RNA-Seq revealed ibrutinib-induced downregulation of genes associated with MDSC-suppressive function (TIMP1, CXCL8, VEGFA, HIF1A), reduced MDSC interactions with exhausted CD8+ T cells, and decreased TCR repertoire diversity. The addition of nivolumab significantly increased circulating NK and CD8+ T cells and increased CD8+ T cell proliferation. Exploratory analyses suggest that MDSC and T cell gene expression and TCR repertoire diversity were differentially affected by BTK inhibition according to patient response.CONCLUSIONIbrutinib and nivolumab were well tolerated and affected MDSC and T cell function in patients with solid metastatic tumors.TRIAL REGISTRATIONClinicalTrials.gov NCT03525925.FUNDINGNIH; National Cancer Institute Cancer; National Center for Advancing Translational Sciences; Pelotonia.

Efficacy and Safety of Ibrutinib as Monotherapy or Combination Therapy in Relapsed/Refractory Diffuse Large B-cell Lymphoma (R/R DLBCL): A Systematic Review and Meta-analysis.

Diffuse large B-cell lymphoma (DLBCL) is a highly heterogeneous disease group. Ibrutinib's monotherapy or combination therapy is effective in relapsed/refractory (R/R) DLBCL. However, the treatment response in R/R DLBCL varies from 15% to 90% with different regimens, and the tolerance remains controversial. The efficacy and safety of ibrutinib monotherapy or combination therapy in patients with R/R DLBCL remain uncertain. The PubMed, CBM, MEDLINE, Cochrane Library, and Embase databases were searched from their inception to July 2021. The total complete remission rate (CRR) and overall response rate in R/R DLBCL patients treated with ibrutinib were 26% and 49%, respectively. The CRR of ibrutinib combination therapy was significantly higher than the ibrutinib monotherapy (45% vs. 19%). Moreover, the CRR of patients was 40% in double expressing lymphoma, 35% in central nervous system lymphoma, and 33% in nongerminal center B-cell-like (non-GCB) DLBCL, which was higher than the 8% in those with the GCB subtype. The pooled median PFS and overall survival were 5.57 and 10.17 months, respectively. GCB-DLBCL had the worst overall survival (5.1 months). Nevertheless, we found that combination regimens had no survival advantage compared with monotherapy (P > 0.05), indicating that combination therapy was only a transitional treatment and bridge for chimeric antigen receptor T cells or other treatments. Moreover, 12% of patients on ibrutinib combination therapy had ≥grade 3 adverse events compared with 9% on ibrutinib monotherapy. Ibrutinib monotherapy or combination therapy was safe and effective in treating R/R DLBCL with tolerable adverse reactions.

Real-World Efficacy and Safety of the Combination of Rituximab, Lenalidomide, and Ibrutinib in Patients with Relapsed and/or Refractory Non-Hodgkin Lymphoma

Real-World Efficacy and Safety of the Combination of Rituximab, Lenalidomide, and Ibrutinib in Patients with Relapsed and/or Refractory Non-Hodgkin Lymphoma

Efficacy and Effectiveness Outcomes of Treatments forDouble-Exposed Chronic Lymphocytic Leukemia and Small Lymphocytic Lymphoma Patients: A Systematic Literature Review.

Bruton's tyrosine kinase inhibitors (BTKi) and the B-cell lymphoma 2 (BCL2) inhibitor venetoclax have significantly improved outcomes and achieved durable remission in patients with chronic lymphocytic leukemia (CLL). BTKi/venetoclax-treated patients with exposure to both novel agents (regardless of the reason for discontinuation) are classified as "double-exposed," and often have poor prognoses. This study aims to assess the efficacy and effectiveness of treatments in double-exposed CLL patients. PubMed, Embase, and Web of Science databases were searched until December 2023. We retrieved 3948 articles for screening and included 13 publications covering nine distinct studies. Three clinical trials reported a median PFS of 16.8 months with pirtobrutinib, 13 months with lisocabtagene maraleucel, and 10.1 months with nemtabrutnib. ORR ranged from 58% with nemtabrutinib and 80% with lisocabtagene maraleucel. In observational studies, PFS ranged from 3 months with chemoimmunotherapy to 12 months with BTKi, and ORR ranged from 31.8% with chemoimmunotherapy to 85.7% with chimeric antigen receptors (CAR)T-cell therapy. This study highlights the limited clinical data on efficacy outcomes for double-exposed CLL/SLL patients. Pirtobrutinib, lisocabtagene maraleucel, and a combination of ibrutinib and venetoclax have shown promising effects. However, the scarcity of treatment options and efficacy data for patients who have failed BTKi and venetoclax underscores a significant unmet medical need.

Dialog between mantle cell lymphoma cells and lymphoma-associated macrophages underlies ibrutinib resistance

IntroductionPatients with mantle cell lymphoma (MCL) frequently develop resistance to ibrutinib. Lymphoma-associated macrophages (LAMs) may play a causal role in this resistance but remain underexplored in current literature. ObjectivesTo elucidate the role of LAMs in mediating ibrutinib resistance in MCL. MethodsWe investigated macrophage polarization through multiparameter flow cytometry (MPFC) using antibodies against CD206 and CD86 in blood and tissue samples from patients with MCL, both resistant and sensitive to ibrutinib. Subsequently, we developed an in vitro co-culture model utilizing MCL cell lines to identify cytokines associated with ibrutinib resistance and macrophage M2 polarization. The mechanisms underlying resistance were examined using MPFC, RNA sequencing, and Western blot analysis. Additionally, we assessed whether SB225002, a CXCR2 inhibitor, could reverse ibrutinib resistance through CCK-8 and caspase-3 assays, as well as in a mouse xenograft model involving an ibrutinib-resistant MCL cell line. ResultsIn patients exhibiting ibrutinib resistance, the ratio of M2 to M1 LAMs was significantly higher compared to sensitive patients. In co-cultures of LAMs and MCL cells, the percentage of M2 macrophages, the IC50 value for ibrutinib, and the concentrations of IL-8 and CXCL5 were significantly elevated. Mechanistically, CXCL5 secreted by LAMs interacted with the CXCR2 on MCL cells, leading to the activation of the Akt, p38, and STAT3 signaling pathways in the presence of ibrutinib; this activity was diminished upon blockade of the CXCL5/CXCR2 axis. The combination of SB225002 and ibrutinib significantly enhanced MCL cell apoptosis, suppressed lymphoma growth in the xenograft model, and reprogrammed macrophage phenotype compared to treatment with ibrutinib alone. ConclusionOur data indicate that M2-polarized LAMs are associated with ibrutinib resistance in a model of MCL, and that a CXCR2 inhibitor can reverse this resistance. These findings suggest a potential new therapeutic strategy.

Ibrutinib in Combination with R-GemOx in Patients with Relapsed or Refractory Diffuse Large B-cell Lymphoma of Nongerminal Center B-cell-like Type: Phase II Clinical Trial of the Spanish GELTAMO Group.

This phase II clinical trial evaluated the combination of ibrutinib with rituximab, gemcitabine, and oxaliplatin (R-GemOx) in patients with nongerminal center B-cell-like (non-GCB) diffuse large B-cell lymphoma (DLBCL). The IBDCL trial (NCT02692248) included patients with histologic diagnosis of non-GCB DLBCL with relapsed or refractory disease and non-candidates for stem-cell transplantation. Patients received an induction treatment consisting of six or eight cycles of R-GemOx at standard doses every 2 weeks, in combination with ibrutinib (560 mg daily), followed by a maintenance treatment with ibrutinib for a maximum of 2 years. The primary objective was to evaluate the overall response rate after four cycles. Sixty-four patients were included, 72% of them refractory to the last regimen. The overall response rate and complete remission rate after the fourth cycle were 53% [95% confidence interval (CI), 41-65] and 34% (95% CI, 24-46), respectively. Twenty-four (37%) patients started maintenance, and 7 (11%) completed the planned 2 years. After a median follow-up of 29.7 months (range: 0.4-48.6), the estimated 2-year progression-free survival and overall survival were 18% (95% CI, 8-28) and 26% (95% CI, 14-37), respectively. The most common grade ≥3 treatment-related adverse events were thrombocytopenia (44%), neutropenia (30%), and anemia (14%). Grade ≥3 infectious and cardiovascular treatment-related adverse events were reported in 6 (9%) and 1 (2%) patient, respectively. Ibrutinib in combination with R-GemOx, followed by ibrutinib maintenance, demonstrated encouraging antitumor activity with durable responses and a manageable toxicity in patients with non-GCB DLBCL.

A phase II study of ibrutinib in combination with ixazomib in patients with Waldenström macroglobulinaemia.

This phase II study evaluated time-limited (24 cycles) treatment with ibrutinib and ixazomib in newly diagnosed (NDWM; n = 9) and relapsed/refractory (RRWM; n = 12) Waldenström macroglobulinaemia (WM). The overall response rate (ORR) was 76.2% (n = 16) in 21 evaluable patients with no patient achieving a complete response (CR). The median duration of treatment was 15.6 months, and after a median follow-up time of 25.7 months, the median progression-free survival (PFS) was 22.9 months. While the primary end-point was not met (CR rate at any time) and 28.5% discontinued treatment due to toxicity, ibrutinib plus ixazomib led to a clinically meaningful ORR and PFS. Combined Bruton's tyrosine kinase (BTK) and proteasome inhibition merits further evaluation in WM.

Brentuximab Vedotin Plus Ibrutinib in Relapsed and Refractory Hodgkin Lymphoma

IntroductionBrentuximab vedotin (BV) is an antibody-drug conjugate that delivers monomethyl auristatin E (MMAE) to CD30+ cells and is safe and effective in relapsed/refractory (r/r) Hodgkin lymphoma (HL). Although most patients respond to BV, only a minority will obtain a complete response (CR), and almost all patients eventually progress.Ibrutinib is a Bruton's tyrosine kinase (BTK) inhibitor highly active in multiple subtypes of non-Hodgkin lymphoma; limited data exist regarding its use in HL. It irreversibly inhibits interleukin-2-inducible kinase (ITK) with Th1 based immune responses. As we previously observed preclinical synergy between ibrutinib and BV, we hypothesized ibrutinib may enhance the antitumor activity of BV in HL. We designed and conducted a phase II trial of ibrutinib plus BV in patients with R/R HL, and herein report the final primary analysis of safety and efficacy. MethodsThis was a multicenter phase II trial with a lead-in cohort in patients with r/r HL. Eligibility criteria included age ≥ 15 years with r/r HL after at least one prior line of therapy. Treatment consisted of 1.8 mg/kg BV intravenously every 3 weeks and ibrutinib 560 mg PO daily (420 mg PO daily in the lead-in cohort). Prior BV was allowed if patients were not refractory. The primary endpoint was the CR rate according to Lugano 2014. Secondary endpoints included toxicities, overall response rate (ORR), and duration of response (DOR). ResultsThe 39 patients were enrolled onto the study, of which 67% were male; the median age was 33 (range: 17-71). 38% had extranodal disease at baseline, 51% had advanced stage disease, 51% were refractory to the prior therapy, and 21% had prior BV. Of 36 patients who were evaluable for response, the CR rate was 33% and ORR 64%; median DOR was 25.5 months. Thirteen patients proceeded to autologous transplant and 3 patients proceeded to allogeneic transplant for consolidation after response. The most common adverse events were nausea (67%), peripheral neuropathy (62%), diarrhea (59%), fatigue (46%), thrombocytopenia (46%), headache (41%), rash (41%), elevated ALT (38%), anemia (36%), vomiting (36%), abdominal pain (33%), fever (33%), and hypertension (33%). Six patients experienced unacceptable toxicity, defined as Gr 3/4 non-hematologic toxicity or non-resolving Gr 3/4 hematologic toxicity including one patient who died of multiorgan failure from suspected COVID-19 infection during cycle 1. DiscussionThe combination of BV and ibrutinib was active in r/r HL; however, given significant toxicity, it cannot be recommended for future development.

Abstract 4002: Investigating CAR-T cell efficacy and activation in the disseminated NALM6-luc human B-cell acute lymphoblastic leukemia model

Abstract Introduction: Chimeric Antigen Receptor T (CAR-T) cell therapy has emerged as a promising approach for treating hematological malignancies, particularly B-cell acute lymphoblastic leukemia (B-ALL). This study aimed to delve into the activation dynamics and therapeutic efficacy of CD19 CAR-T cells in a disseminated NALM6-luc human B-ALL murine model. Experimental design: NALM6-Luc-mCh-Puro cells were implanted intravenously in female NSG (NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ) mice. Animals were treated with CD19 CAR-T cells alone and in combination with ibrutinib. The anti-tumor activity was assessed, and the persistence and activation of CAR-T cells in the blood were evaluated using flow cytometry. Additionally, ddPCR analysis was employed to quantify CAR copy numbers, providing insights into the T-cell persistence over time. Results: Treatment with CD19 CAR-T cells exhibited notable anti-cancer activity and that activity was enhanced in combination with ibrutinib, in line with other reports. The increased time to progression was noted as 69.2% for the CAR-T group and 138.4% for the combination of CAR-T and ibrutinib compared to control. Flow cytometry analysis showed that CAR-T cells persisted in the blood throughout the study. The mean CAR-T absolute cell count for both CAR-T and CAR-T plus ibrutinib treated groups increased from 2 cell/µL blood on Day 0 to 11 and 51 cells/µL of blood, respectively, by Day 39. The progressive increase of PD-1+ and LAG-3+ percentage cells correlates positively with tumor burden, indicating a dynamic link between biomarker upregulation and the presence of tumor cells in mice. ddPCR analysis revealed an initial CAR copy decrease in all groups, followed by gradual increase in tumor-bearing mice treated with CD19 CAR-T cells, with a dramatic increase observed by Day 39. Results from CAR-T treated and CAR-T plus ibrutinib treated groups were comparable, showing mean copy numbers per ng of DNA increasing from less than 1 on day 4 to 17.9 and 23.3, respectively, on day 39. Importantly, no changes were noted in non-tumor implanted mice, emphasizing the tumor dependency for CAR-T cell expansion. Conclusion: This study emphasizes the marked anti-cancer activity of CD19 CAR-T cells in the NALM6-Luc-mCh-Puro B-ALL murine model. Comprehensive analysis of CAR-T cell persistence and activation, including insights from ddPCR, provides a robust understanding of therapeutic response dynamics. The observed in vivo anti-cancer efficacy aligns with the persistence of CAR-T cells revealed by flow cytometry and the dynamic expansion captured through ddPCR analysis. Our results indicate ddPCR and flow cytometry as complementary and independent methods for assessing the systemic CAR-T cell persistence, contributing to optimizing therapy for B-cell acute lymphoblastic leukemia. Citation Format: Prashant Pandey, David Draper, Sheri Barnes, Yewei Xing, Derrik Germain, Lauren Kucharczyk, Roys Stacey. Investigating CAR-T cell efficacy and activation in the disseminated NALM6-luc human B-cell acute lymphoblastic leukemia model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4002.

Combination of Ibrutinib and Venetoclax in the Therapy of Chronic Lymphocytic Leukemia: A Review of the Latest Data from Clinical Studies

New Bruton’s tyrosine kinase (BTK) inhibitors caused drastic modifications in the therapy of chronic lymphocytic leukemia (CLL). Ibrutinib, the first in its class BTK inhibitor, showed high efficacy in many clinical studies. However, the treatment with BTK inhibitors as monotherapy must not be discontinued. Ibrutinib monotherapy inevitably leads to BTK inhibitor resistance and severe adverse events, which often results in treatment failure. Inhibitor BCL-2 venetoclax combined with BTK inhibitor can increase the therapy efficacy due to the synergetic effect of these agents on different CLL cell populations. Combined therapy potentially providing fixed-duration treatment can yield deeper responses. The present review focuses on ibrutinib and venetoclax combination, summarizes the latest data from clinical studies, and deals with feasibility of combined therapy in terms of its efficacy and safety profile.

Ibrutinib (Imbruvica)


 CADTH reimbursement reviews are comprehensive assessments of the clinical effectiveness and cost-effectiveness, as well as patient and clinician perspectives, of a drug or drug class.
 The assessments inform non-binding recommendations that help guide the reimbursement decisions of Canada's federal, provincial, and territorial governments, with the exception of Quebec.
 This review assesses ibrutinib (Imbruvica) 140 mg capsule, oral.
 Indication: Ibrutinib in combination with venetoclax for the treatment of adult patients with previously untreated chronic lymphocytic leukemia, including those with 17p deletion.

The experience of relapsed Burkitt lymphoma treatment with targeted drugs and autologous/allogeneic stem cell transplantation

The use of high-effective, multicomponent, risk-adopted chemoimmunotherapy schemes in children with Burkitt lymphoma reached advanced long-term progression-free survival over 90 % even for high risk patients. Unfortunately, conventional therapeutic strategy for relapsed/refractory disease is not accepted, and the effectiveness of carboplat‑in- and gemcitabine-containing regimens is unsatisfactory. Clinical experience of rituximab, ibrutinib and nivolumab in combination with polychemotherapy and own clinical case of successful relapsed Burkitt lymphoma treatment with targeted therapy and following autologous and allogeneic hematopoietic stem cell transplantation are presented. Proposed program could achieve a complete remission of Burkitt lymphoma, but short-term after allogeneic hematopoietic stem cell transplantation diagnosed T-cell precursor acute lymphoblastic leukemia became fatal for the patient.

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

AbstractA041202 (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.

Chronic Lymphocytic Leukemia Therapy Guided by Measurable Residual Disease

BackgroundThe combination of ibrutinib and venetoclax has been shown to improve outcomes in patients with chronic lymphocytic leukemia (CLL) as compared with chemoimmunotherapy. Whether ibrutinib–venetoclax and personalization of treatment duration according to measurable residual disease (MRD) is more effective than fludarabine–cyclophosphamide–rituximab (FCR) is unclear.MethodsIn this phase 3, multicenter, randomized, controlled, open-label platform trial involving patients with untreated CLL, we compared ibrutinib–venetoclax and ibrutinib monotherapy with FCR. In the ibrutinib–venetoclax group, after 2 months of ibrutinib, venetoclax was added for up to 6 years of therapy. The duration of ibrutinib–venetoclax therapy was defined by MRD assessed in peripheral blood and bone marrow and was double the time taken to achieve undetectable MRD. The primary end point was progression-free survival in the ibrutinib–venetoclax group as compared with the FCR group, results that are reported here. Key secondary end points were overall survival, response, MRD, and safety.ResultsA total of 523 patients were randomly assigned to the ibrutinib–venetoclax group or the FCR group. At a median of 43.7 months, disease progression or death had occurred in 12 patients in the ibrutinib–venetoclax group and 75 patients in the FCR group (hazard ratio, 0.13; 95% confidence interval [CI], 0.07 to 0.24; P<0.001). Death occurred in 9 patients in the ibrutinib–venetoclax group and 25 patients in the FCR group (hazard ratio, 0.31; 95% CI, 0.15 to 0.67). At 3 years, 58.0% of the patients in the ibrutinib–venetoclax group had stopped therapy owing to undetectable MRD. After 5 years of ibrutinib–venetoclax therapy, 65.9% of the patients had undetectable MRD in the bone marrow and 92.7% had undetectable MRD in the peripheral blood. The risk of infection was similar in the ibrutinib–venetoclax group and the FCR group. The percentage of patients with cardiac serious adverse events was higher in the ibrutinib–venetoclax group than in the FCR group (10.7% vs. 0.4%).ConclusionsMRD-directed ibrutinib–venetoclax improved progression-free survival as compared with FCR, and results for overall survival also favored ibrutinib–venetoclax. (Funded by Cancer Research UK and others; FLAIR ISRCTN Registry number, ISRCTN01844152; EudraCT number, 2013-001944-76.)

Studies on Fixed Dose Combination of Ibrutinib and Quercetin Self-Nanoemulsifying Drug Delivery Systems in Human Cancer Cell Lines

Ibrutinib (IB), irreversibly inhibits Bruton’s tyrosine kinase which plays a crucial role in the tumor microenvironment and quercetin (QC) has shown apoptosis induction, angiogenesis inhibition, and anti-proliferative action against several human carcinoma cells. The self-nano-emulsifying drug delivery system (SNEDDS) is suitable for loading insolubilized oil-based compounds such as ibrutinib and quercetin. In the current study IB with QC was formulated into SNEDDS and cytotoxicity was determined by using human malignant melanoma (A-375) and human lung adenocarcinoma (A549) cell lines. The optimized loaded formula consisted of castor oil, Kolliphor® RH 40, and PEG-600. The optimized formulation was evaluated for physical parameters and the results were satisfactory. For cytotoxicity studies MTT assay was conducted for these combinations, IC50 values were calculated for the tested compound. In A-549 adenocarcinoma cell line, the calculated IC50 values (μM) for the test compounds T1 (pure IB ± QC) and T2 (IB ± QC SNEDDS) were 70.34 ± 0.8 and 85.46 ± 0.93 μM at 24 hours study, respectively. In A-375 cancer cell line, IC50 values for the compounds T1 and T2 were 59.52 ± 0.87 and 88.43 ± 1.03 μM for 24 hours study, respectively. It was observed that the IC50 of IB-QC loaded SNEDDS was higher than pure drug combination and these enter the cells by active transport and induce cytotoxicity to the cells. The overall results from the studies suggest that IB-QC-loaded SNEDD provided synergistic effects, which could play a significant role in the percentage of cell death.

Efficacy of Protac-Based EZH2 Degrader MS1943 in Lymphoid Malignancies: A Comprehensive Study on the Combined Effects of MS1943 and Ibrutinib

Introduction: This study delves into the therapeutic potential of the Enhancer of zeste homolog 2 (EZH2) degrader MS1943 and the Bruton's tyrosine kinase (BTK) inhibitor Ibrutinib in B-cell lymphomas. The study's primary objective was to compare the efficacy of MS1943, a Proteolysis-targeting chimera (PROTAC)-based degrader, with the FDA-approved EZH2 inhibitor Tazemetostat. The study also aimed to explore the potential synergistic effects of combining these therapies with Ibrutinib, a widely used BTK inhibitor in lymphoma treatment. Materials and Methods: The study employed a range of lymphoma cell lines, including B-cell and T-cell lymphomas, which were treated with MS1943, Tazemetostat, and Ibrutinib, either alone or in combination. The impact of these treatments on cell viability was evaluated using the Cell Counting Kit-8 (CCK-8) assay at different time points and concentrations. Cell cycle distribution was assessed using flow cytometric analysis, and the expression of downstream effectors of the unfolded protein response (UPR) pathway, including Xbp1, Chop, and Bip, was examined using quantitative polymerase chain reaction (qPCR). Western blot analysis was performed to investigate the association with specific apoptosis-related pathways. Results: The results demonstrated that MS1943 exhibited significantly greater inhibitory effects than Tazemetostat in all lymphoma cell lines tested, particularly in B-cell lymphomas. MS1943 treatment resulted in increased expression of UPR pathway effectors, suggesting a correlation between the observed anti-proliferative effects and the differential expression of these factors. The combination of MS1943 and Ibrutinib demonstrated significant inhibitory effects across all B-cell lymphoma cell lines, with the most prominent cytotoxicity observed after 72 hours of culture. The combination treatment resulted in an increase in the number of cells in the G2/M phase, accompanied by a decrease in the number of cells in the G0/G1 phase. Furthermore, the combination treatment led to a notably higher proportion of apoptotic and necroptotic cells compared to either individual treatment or the combination of Ibrutinib and Tazemetostat. The combination treatment resulted in an increase in the expression of p53 and PUMA, and a significant increase in miR29b expression. Discussion: Our findings suggest that the simultaneous treatment of MS1943 and Ibrutinib in B-cell lymphoma induces apoptosis through the miR29b-mediated p53 upregulated pathway, thereby exhibiting potent anti-tumor effects. The study provides compelling evidence that MS1943 exhibits a pronounced inhibitory effect on B-cell lymphomas compared to Tazemetostat, highlighting its potential as a promising therapeutic agent in the treatment of B-cell lymphomas. The combination of MS1943 and Ibrutinib enhances apoptotic and necroptotic cell death, resulting in a significant reduction in viable cells. This study provides valuable insights into the mechanisms underlying the anti-tumor effects of this drug combination, highlighting the potential of MS1943 as an effective treatment option for lymphoma.

Ibrutinib in Combination with Revlimid/Dexamethasone (Rd) in Relapsed/Refractory Multiple Myeloma (AFT-15)

Introduction: Preclinical studies have suggested synergism between lenalidomide (LEN) and ibrutinib (IBR) in multiple myeloma (MM). Both downregulate IRF4, a master transcriptional factor that regulates myeloma cell survival. Single agent oral IBR combined with dexamethasone proved well tolerated and active in advanced, steroid refractory relapsed MM as part of a large Phase1/2 study in 60 patients, with durable stabilization and minimal response seen in most evaluable patients (Richardson PG et al, BJH 2018). LEN is considered a standard of care in newly diagnosed MM, as maintenance and in relapsed disease, and a backbone of oral therapy in the MM treatment paradigm (Laubach JP et al, Leukemia 2016). Methods: We therefore conducted a 3+3 phase I trial to determine the maximum tolerated dose (MTD) of IBR in combination with LEN + dexamethasone (DEX) in patients with relapsed/refractory (RR) MM who had at least 2 prior lines of therapy. Three dose levels (DL) were planned. Cycle length was 28 days. IBR was administered orally daily at 560mg on DL1-2 and 840mg on DL3, LEN orally days 1-21 at 15mg on DL1 and 25mg on DL2-3, and DEX orally days 1, 8, 15, and 22 at 40 mg if age &amp;lt; 75 or 20 mg if ≥75 for DL1-3. Patients with GFR ≥ 30 and &amp;lt; 60 were treated according to manufacturer's instructions with lenalidomide dosed at 10mg/d. Dose limiting toxicities (DLT) included grade 4 thrombocytopenia; grade 4 neutropenia lasting more than 5 days or febrile neutropenia; grade 4 nausea, vomiting or diarrhea; grade 3 thrombocytopenia with bleeding or platelet transfusion; grade 3-4 hyperglycemia or thrombotic/embolic event, treatment delays ≥ 21 days for toxicity; and treatment related death. Due to changes in standard of care during the study, eligibility was modified to allow the enrollment of patients with RRMM who had at least 1 prior line of therapy. Response was assessed using IMWG/Uniform Criteria. Results: Fourteen patients (DL1-6 pts; DL2-3 pts; DL3-5 pts) registered to the study from March 2019 to May 2023, prior to its closure due to slow accrual. One patient on DL3 cancelled participation prior to start of treatment due to disease progression (PD). The remaining 13 patients are included in summary of toxicities and response but 2 patients on DL3 are excluded from determination of MTD due to discontinuing cycle 1 treatment due to COVID and receiving 280 mg/day of IBR instead of assigned 840 mg/day dose during cycle 1, respectfully. Twelve patients were evaluable for response. The median number of prior lines of therapy was 3 (range: 2-9), reflecting a heavily pretreated relapsed and refractory population. One of the 6 patient on DL1 developed a DLT, grade 3 non-viral hepatitis. None of the 3 patients on DL2 or the 2 patients on DL3 had a DLT. One patient on DL1 remains on treatment with stable disease for 42+ cycles. The median number of cycles administered was 3 (range: 1-42+). Severe toxicities reported included grade 3 lymphocytopenia (3), anemia (2), alanine aminotransferase increase (1), aspartate aminotransferase increase (1), blood bilirubin increase (1), hypocalcemia (1), hypokalemia (1) hypophosphatemia (1), febrile neutropenia (1), chronic kidney disease (1), non-viral hepatitis (1), soft tissue infection (1), and fatigue (1); grade 4 lymphocytopenia (1), and grade 5 sepsis (1). End of treatment reasons included: PD (7), toxicity (2), death [soft tissue infection that turned into sepsis considered to be likely related to DEX] (1), and concomitant conditions (2). Stable disease (SD) or better was achieved in 10 of 12 evaluable patients (83%), including one patient who achieved disease control for over 3.5 years. One patient (8%) on DL3 had a complete response (CR) but stopped treatment after 2 cycles due to reversible toxicity and comorbid conditions, based upon physician advice and patient choice. Conclusions: The combination of lenalidomide with Ibrutinib as an all-oral approach in RR MM proved feasible and generally tolerable, with the majority of discontinuation seen in this Phase I study due to disease progression. No COVID related - mortality was seen. SD or better was achieved in 83% of patients, including one CR. Potential future directions include combination approaches with next generation IMids such as pomalidomide, as well as other orally bioavailable novel agents with potent immune activating properties, such as CelMoDs. Support: AFT; Pharmacyclics; Clinicaltrials.gov Identifier: NCT03702725

Combination of Ibrutinib with CD19 Chimeric Antigen Receptor (CAR) T Cells Suggests Greater Contribution to CAR T-Cell Efficacy Than Other Approved BTK Inhibitors in the Preclinical Setting

Background: CD19-directed CAR T-cell therapy has demonstrated remarkable clinical benefits for patients with B-cell malignancies, but impaired CAR T-cell fitness can result in lack of response or relapse. Rational combinations that enhance T-cell fitness may overcome primary and secondary resistance. Bruton tyrosine kinase inhibitors (BTKi), such as Ibrutinib (Ibr) have been shown to enhance CAR T-cell efficacy (Fraietta et al, Blood 2016;Liu et al, Cancer Sci 2020), but the precise mechanism remains unclear. In addition to BTK, Ibr potently inhibits IL-2-inducible tyrosine kinase (ITK), an important mediator of T-cell signaling. Ibr has been shown to enhance Th1 polarization through suppression of the Th2 differentiation pathway, thereby potentiating a cytotoxic effector response (Qin et al, J Immunother 2020). Consistent with this finding, the Th1 phenotype was more frequent in peripheral blood mononuclear cells of Ibr-exposed patients than in acalabrutinib (Acala)-exposed patients (Scarfò et al, Blood 2021). Therefore, we aimed to assess the potential impact of ITK inhibition (ITKi) on CD19 CAR T-cell function by comparing Ibr to other approved BTKi that display low or no ITKi activity (Estupiñán et al, Front Cell Dev Biol 2021). Methods: CD19-41bb CAR T cells (CAR19) were generated by lentiviral transduction of healthy donor T cells. BTKi additivity to CAR19 function was evaluated in a Luciferase (Luc)+ Ramos, BTKi resistant systemic tumor model in NSG mice co-treated with covalent BTKis Ibr, Acala, zanubrutinib (Zanu), and CAR T cells. Next, to evaluate the impact of ITKi on CAR19 fitness and cytotoxicity, repeated stimulation in an in vitro cytotoxicity assay was performed at low CAR19 effector-to-tumor ratio (1:20) to mimic higher tumor burden stress conditions in the presence of each BTKi, including non-covalent BTKi pirtobrutinib (Pirto) (500 nM). Tumor cells were replenished every 3 days and cytotoxicity was measured on day 7 by luciferase assay. For phenotypic characterization, CAR T cells were repeatedly stimulated by plate-bound anti-Whitlow linker every 3 days. Viability and proliferation were measured by cell counter. Flow cytometry (FACS) was performed on surface and intracellular T-cell phenotypic, activation, and exhaustion markers. Metabolic fitness (glycolysis and ATP production) was characterized using Seahorse (Van der Windt, 2012). Impact of Ibr on signal strength was evaluated in CD19-expressing Jurkat reporter cells (CAR-J19) with knock-in of mKate in frame with Nur77. Ibr was added to coculture of CAR-J19 and tumor cells and upregulation of Nur77 was measured by FACS. Downstream ITK signaling pathway was measured by Western blot. Results: Preliminary in vivo experiments demonstrated that co-administration of each BTKi with CD19 CAR T cells improved tumor control at day 26 (N=5 per group; P≤0.0004 vs CAR T cells alone). In serial killing experiments, addition of Ibr to the coculture increased proliferation (n=2; P&amp;lt;0.05), viability (n=2; P=0.01), and the cytotoxicity of CAR T cells against Ramos cells ( P=0.02 vs CAR19 alone) to a greater extent than other BTKis tested (Fig. 1A). Prolonged stimulation of CAR19 with Ibr led to downregulation of activation and inhibitory markers on CAR19 and maintenance of a naive T-cell phenotype (Fig. 1B) that was confirmed by increased metabolic fitness (n=5; P&amp;lt;0.05). Addition of Ibr to CAR-J19 resulted in a 72% reduction in CAR activation and reduced phosphorylation of ITK, PLCG, and Zap70. Additional data including the impact of ITK knockout on CAR-T cells will be presented. Conclusions: Our study expands on the hypothesized mechanism of action underlying the clinical benefit observed with Ibr in CD19 CAR T-cell-treated patients with chronic lymphocytic leukemia or mantle cell lymphoma (Liu et al, Front Immunol 2022; Wang et al, NEJM 2020). Our data suggest that Ibr enhances CAR T-cell fitness to a greater extent than both covalent and noncovalent BTKi that display reduced or no ITKi activity. Through ITKi, Ibr tempers CAR T-cell activation induced cell death, maintains a naive state and prevents premature exhaustion, thereby enabling more efficacious tumor cell killing over time. Together, these data support the further exploration of Ibr to enhance CD19 CAR T-cell efficacy.

Minimal Residual Disease-Guided Combination of Ibrutinib and Venetoclax Compared to FCR in Untreated Patients with CLL of Intermediate Risk : Interim Results of MRD Kinetics in the Eradic Trial from the Filo Group

With the emergence of targeted therapies, defining the best strategy for first-line treatment in chronic lymphocytic leukemia (CLL) patients has become challenging. The aim of the ERADIC phase 2 study was to compare the efficacy of a standard FCR regimen to that of an MRD-guided combination of ibrutinib and venetoclax (IV), in fit patients with CLL of intermediate risk defined by either unmutated IGHV status, 11q deletion or complex karyotype in the absence of TP53 alteration. MRD was assessed in bone marrow (BM) or peripheral blood (PB) by flow cytometry. After a lead-in phase of ibrutinib as a single agent from month (M)1 to M3, the total duration of treatment with the IV combination was based on BM M9 MRD. If it was &amp;lt;0.01% (uMRD) at that time, treatment was continued for 6 additional months (M15) then stopped. If M9 BM-MRD was ≥0.01%, IV treatment was continued for 18 additional months (M27). BM-MRD was reassessed at that time-point in both arms. Additionally, PB-MRD evaluation was performed every 6 months.The primary endpoint will be the percentage of patients with BM uMRD at M27. Here, intermediate safety data and MRD kinetics (M9 to M21) are presented. Between September 2019 and February 2021, 120 patients were randomized 1:1 between the two treatment arms. The median age was 59 [34-72] and 61 [34-74] year-old in the FCR and IV arms, respectively. Patient characteristics were well balanced between the 2 arms in terms of gender (male 72% FCR, 74% IV), PS ECOG 0-1 (59% FCR, 68% IV) and Binet stage (A, B and C 15%, 64%, 21% for FCR ; 8.5%, 59% and 32% for IV). An11q deletion was found in 20% and 24% of the cases in the FCR and IV arms, respectively and all patients but one had unmutated IGHV. At the time of data cut-off for this analysis, the median follow-up was 29.7 months [range: 25.3- 32.8]. Sixty-three serious adverse events (SAE) have been reported so far, 32 in the FCR arm and 31 in the IV arm. In the FCR arm, the most frequent SAE were infections (N=12 including 4 COVID-19), febrile neutropenia (N=5) biological tumour lysis syndrome (N=3), and secondary malignancies (N=2, including 1 myelodysplastic syndrome and 1 acute myeloid leukemia). In the IV arm, the most frequently reported SAE were infections (N=8 including 4 COVID-19), cardiovascular events (N=7), biological tumour lysis syndrome (N=5), acute renal failure (N=2) and secondary malignancies (N=2, including 1 colorectal cancer and 1 skin basal cell carcinoma). Four grade 5 adverse events were reported, respectively 2 in the FCR arm (1 septic shock and 1 AML) and 3 in the IV arm (2 sudden deaths and one death COVID-19-related). In the FCR arm (intention to treat [ITT] n=57), 59.6% of the patients had BM-uMRD at M9. The kinetics of PB-uMRD was 68% at M9, 65% at M15 and 52% at M21. In the IV arm (ITT n=54), the rate of BM-uMRD at M9 was much lower at 33%. PB-MRD kinetics showed levels of uMRD of 52%,70% and 67% at M9, M15 and M21 respectively. In terms of response, CR/CRi rates were 56% for the FCR arm and 66% for the IV arm. Three patients progressed in the FCR arm (1 at M9 and 2 at M15) and 2 in the IV arm, at respectively M13 and M39. Among the 13 patients who achieved BM-uMRD at M9 in the IV arm, 10 have indeed stopped according to the protocol and only 1 has progressed at M39. In conclusion, monitoring MRD kinetics in this trial showed a stable level of PB-uMRD in the FCR arm yet a clear increase in the IV arm between M9 and M15. Toxicity remains an important parameter in both treatment arms that will have to be taken into account when determining whether treatment should be continued because of detectable BM-MRD at M9 (IV arm). Upcoming data of the primary enpoint analysis at M27 will be of great interest to try to determine the best strategy.

Six Years Follow up of Ibrutinib Plus Rituximab (IR) Followed By Short Course R-Hyper CVAD/MTX in Patients (age ≤ 65 years) with Previously Untreated Mantle Cell Lymphoma - Phase-II Window-1 Clinical Trial

Background - We reported the efficacy and safety of using a combination of ibrutinib plus rituximab (IR) induction followed by short course (4 cycles) of R-HCVAD/MTX-ara-C as consolidation in previously untreated young (age ≤ 65 years)patients (pts) with mantle cell lymphoma (MCL), Wang M et al Lancet Oncology 2022. Here we report the long term follow up of this study. Methods - We enrolled 131 previously untreated pts in this single institution, single arm, phase II clinical trial - NCT02427620. Pts received IR induction (part-A), until they achieved complete remission (CR) for up to a maximum of 12 cycles, followed by a maximum of 4 cycles of R-HCVAD/R-MTX-ara-C (part-B) as consolidation. The primary objective was to assess overall response rate (ORR), [defined as either a partial response (PR) or a complete response (CR)] after part A. Adverse events were coded as per CTCAE version 4. High risk pts received ibrutinib for 1 year and rituximab once every 2 months for 24 months after completion of part B. Results - Among the 131 pts, the median age was 56 yrs (range - 35-65). High Ki-67 (≥30%) in 58/117 (49.5%) pts, 10 pts (8%) had high risk simplified MIPI score, 15 pts (11%) had aggressive MCL (blastoid/pleomorphic) and 114 pts (87%) had initial bone marrow involvement. Fifty percent of the patients had Ki-67 (≥30%). ORR in part-A was 98% (87% CR). After completion of part A and part B, ORR was 90% (89% CR). After a median follow up of 71 months, 43 patients progressed/died. The median progression free survival (PFS) and overall survival (OS) were not reached. Overall, 30 pts (23%) relapsed after treatment, including 5 who transformed to aggressive MCL. PFS among pts with high and low Ki-67% was 42 months vs not reached (P=0.01) while no difference was observed in OS. PFS was significantly shorter in pts with aggressive histology (p=0.001) but not the OS. PFS was similar in pts who received maintenance vs no maintenance therapy. Overall, 8 pts died (4 with progression, 2 due to disease transformation, one on study due to multiple complications including splenic hematoma, cardio-pulmonary arrest and progression and the last one expired outside and came off study due to encephalitis). 50 pts came off study for various reasons [30 disease progression (including 5 transformation), 10 pt choice, 8 intolerance, 1 second cancer and 1 lost to follow up]. Long term, grade 3-4 toxicities on part A were 6% myelosuppression and 10% each with fatigue, myalgia and rashes and 2% mucositis. Maintenance therapy did not show high toxicities. Conclusions -Long term follow up of chemo-free induction with IR induced durable and deep responses in young MCL pts in the frontline setting. Short course R-HCVAD chemotherapy minimized toxicities and consolidated responses. IR maintenance improved survival outcomes. This combined modality treatment approach may significantly improve young MCL pts outcomes across all risk groups.