PURPOSE:

To determine the role of CD49d for response to Bruton's tyrosine kinase inhibitors (BTKi) in patients with chronic lymphocytic leukemia (CLL).

PATIENTS AND METHODS:

In patients treated with acalabrutinib (n = 48), CD49d expression, VLA‐4 integrin activation, and tumor transcriptomes of CLL cells were assessed. Clinical responses to BTKis were investigated in acalabrutinib‐ (n = 48; NCT02337829) and ibrutinib‐treated (n = 73; NCT01500733) patients.

RESULTS:

In patients treated with acalabrutinib, treatment‐induced lymphocytosis was comparable for both subgroups but resolved more rapidly for CD49d+ cases. Acalabrutinib inhibited constitutive VLA‐4 activation but was insufficient to block BCR and CXCR4‐mediated inside‐out activation. Transcriptomes of CD49d+ and CD49d‐ cases were compared using RNA sequencing at baseline and at 1 and 6 months on treatment. Gene set enrichment analysis revealed increased constitutive NF‐κB and JAK‐STAT signaling, enhanced survival, adhesion, and migratory capacity in CD49d+ over CD49d‐ CLL that was maintained during therapy. In the combined cohorts of 121 BTKi‐treated patients, 48 (39.7%) progressed on treatment with BTK and/or PLCG2 mutations detected in 87% of CLL progressions. Consistent with a recent report, homogeneous and bimodal CD49d‐positive cases (the latter having concurrent CD49d+ and CD49d‐ CLL subpopulations, irrespective of the traditional 30% cutoff value) had a shorter time to progression of 6.6 years, whereas 90% of cases homogenously CD49d‐ were estimated progression‐free at 8 years (P = 0.0004).

CONCLUSIONS:

CD49d/VLA‐4 emerges as a microenvironmental factor that contributes to BTKi resistance in CLL. The prognostic value of CD49d is improved by considering bimodal CD49d expression.

Of the variety of immunoglobulin related amyloidosis (AL), immunoglobulin M (IgM) related AL represents only 6 to 10% of affected patients, and the majority of these cases are associated with underlying non-Hodgkin's Lymphoma including Waldenström's macroglobulinemia (WM). Ibrutinib, acalabrutinib, and zanubrutinib are Bruton tyrosine kinase (BTK) inhibitors approved for certain indolent B cell non-Hodgkin's lymphoma (NHL). BTK is a nonreceptor kinase involved in B-cell survival, proliferation, and interaction with the microenvironment. We retrospectively evaluated the tolerability and effectiveness of BTK inhibitors ibrutinib and acalabrutinib therapy in (n = 4) patients with IgM-related AL amyloidosis with underlying WM. Treatment was well tolerated with both hematologic and organ response in patients with AL amyloidosis in the setting of WM. Atrial fibrillation led to the discontinuation of ibrutinib in one patient, and acalabrutinib caused significant thumb hematoma needing dose reduction in another patient. All patients evaluated had the MYD88 mutation. This may explain the good response to BTK inhibitors therapy in our series. BTK inhibitors should be further investigated in larger prospective studies for treatment of AL amyloidosis in patients with lymphoplasmacytic lymphoma/WM.

The treatment of chronic lymphocytic leukemia (CLL) currently relies on the use of chemo-immunotherapy, Bruton's tyrosine kinase inhibitors, or BCL2 inhibitors alone or combined with an anti-CD20 monoclonal antibody. However, the availability of multiple choices for the first-line setting and a lack of direct head-to-head comparisons pose a challenge for treatment selection. To overcome these limitations, we performed a systematic review and a network meta-analysis on published randomized clinical trials performed in the first-line treatment setting of CLL. For each study, we retrieved data on progression-free survival (according to del17/P53 and IGHV status), overall response rate, complete response, and incidence of most frequent grade 3-4 adverse event. We identified nine clinical trials encompassing 11 different treatments, with a total of 5288 CLL patients evaluated. We systematically performed separated network meta-analyses (NMA) to evaluate the efficacy/safety of each regimen in the conditions previously described to obtain the surface under the cumulative ranking curve (SUCRA) score, which was subsequently used to build separated ranking charts. Interestingly, the combination of obinutuzumab with acalabrutinib reached the top of the chart in each sub-analysis performed, with the exception of the del17/P53mut setting, where it was almost on par with the aCD20 mAbs/ibrutinib combination (SUCRA aCD20-ibrutinib and O-acala: 93.5% and 91%, respectively) and of the safety evaluation, where monotherapies (acalabrutinib in particular) gave better results. Finally, considering that NMA and SUCRA work for single endpoints only, we performed a principal component analysis to recapitulate in a cartesian plane the SUCRA profiles of each schedule according to the results obtained in each sub-analysis, confirming again the superiority of aCD20/BTKi or BCL2i combinations in a first-line setting. Overall, here we demonstrated that: (1) a chemotherapy-free regimen, such as the combination of aCD20 with a BTKi or BCL2i, should be the preferred treatment choice despite biological/molecular characteristics (preferred regimen O-acala); (2) there is less and less room for chemotherapy in the first line treatment of CLL.

Introduction: Frequent and durable responses were recently reported in relapsed or refractory (R/R) mantle cell lymphoma (MCL) patients treated with KTE-X19, an autologous CD19-targeted chimeric antigen receptor-engineered T-cell (CAR-T) product (Wang et al. N Engl J Med. 2020). Most patients enrolled had received at least one line of Tec kinase inhibitor prior to KTE-X19 manufacturing, either in the form of ibrutinib, a Bruton's tyrosine kinase (BTK) and Inducible T cell kinase (ITK) inhibitor, or acalabrutinib, a more selective BTK inhibitor. Pharmacokinetic expansion of KTE-X19 was higher in ibrutinib-treated patients relative to acalabrutinib-treated patients. We previously showed that prolonged exposure to ibrutinib enhanced T cell effector function and proliferation in patients with CLL (Fraietta et al, Blood, 2016). To assess the impact of Tec kinase inhibitor on KTE-X19 products and downstream clinical outcomes, we examined the phenotype, transcriptional profile and cytokine production of KTE-X19 infusion products and post-infusion lymphocytes from patients with R/R MCL treated on the Zuma-2 study. Study Design and Methods: We evaluated biospecimens from MCL patients who enrolled on the Zuma-2 clinical trial (NCT02601313) and who were previously treated with ibrutinib (n=14) or acalabrutinib (n=6). Samples analyzed consisted of KTE-X19 CAR T products and peripheral blood mononuclear cells (PBMC) collected 7 days after infusion. Lymphocytes were assessed for CAR expression, T cell phenotype, transcriptional profile and cytokine production. In addition, CAR T cell phenotypes and cytokines were profiled following co-culture of KTE-X19 with CD19 + Toledo cells (DLBCL). Results: Flow cytometric analysis of KTE-X19 demonstrated similar distributions of CD4+ and CD8+ T cells and comparable frequencies of central and effector memory populations in the CAR+ T cells derived from patients with prior exposure to ibrutinib vs. acalabrutinib. T helper subset analysis trended towards enrichment of Th1/Th17 populations within the CAR+ CD4+ cells of the ibrutinib cohort. This finding was further supported by transcriptional profiling of sorted CAR+ T cells from infusion products, where Th1/Th17, Jak/STAT and activation-related genes were enriched in the cohort with prior ibrutinib exposure. In addition, the Th1 phenotype was more frequent in PBMC of ibrutinib-exposed patients (8/14) compared to acalabrutinib-exposed patients (1/4). Interestingly, a shift from a central memory-dominant product towards an effector memory phenotype was observed in peripheral CD4+ and CD8+ CAR T cells in the ibrutinib cohort, whereas acalabrutinib post-infusion CAR T cells maintained a central memory phenotype. In vitro stimulation of KTE-X19 CAR-T infusion products with tumor cells resulted in a significant enrichment of the Th1 population in patients who had received ibrutinib compared to those that received acalabrutinib (p=0.0058). Following stimulation, CAR-T cells from the acalabrutinib cohort produced higher levels of Th2 cytokines, including IL-4, IL-5, and IL-13 as well as GM-CSF compared to the ibrutinib cohort. Conclusions: Analysis of KTE-X19 infusion products and day 7 post-infusion PBMC demonstrated that CAR T cells from patients with prior ibrutinib exposure have a Th1 predominant phenotype, suggesting that ibrutinib but not acalabrutinib promotes Th1 differentiation and effector function, potentially through the inhibition of ITK. Furthermore, our data suggest that inhibition of non-BTK targets such as ITK may play a role in driving a Th17 phenotype. Prior exposure to ibrutinib may increase CAR T cell effector function to a greater extent than exposure to acalabrutinib to enhance clinical outcome in patients with MCL. Disclosures: Budka: Kite Pharma: Current Employment. Sowrirajan: Kite Pharma: Current Employment. Nguyen: Kite Pharma: Current Employment. Shen: Gilead Sciences: Current equity holder in publicly-traded company; Kite, a Gilead Company: Current Employment, Other: Leadership role, Patents & Royalties; Atara: Current Employment, Current equity holder in publicly-traded company, Other: Leadership role, Patents & Royalties. Bot: Kite, a Gilead Company: Current Employment; Gilead Sciences: Consultancy, Current equity holder in publicly-traded company, Other: Travel support. Maus: Agenus: Consultancy; Arcellx: Consultancy; Astellas: Consultancy; AstraZeneca: Consultancy; Atara: Consultancy; Bayer: Consultancy;

BMS:

Consultancy; Cabaletta Bio (SAB): Consultancy; CRISPR therapeutics: Consultancy; In8bio (SAB): Consultancy; Intellia: Consultancy;

GSK:

Consultancy; Kite Pharma: Consultancy, Research Funding; Micromedicine: Consultancy, Current holder of stock options in a privately-held company; Novartis: Consultancy; Tmunity: Consultancy; Torque: Consultancy, Current holder of stock options in a privately-held company; Wind

MIL:

Consultancy; Adaptimmune: Consultancy; tcr2: Consultancy, Divested equity in a private or publicly-traded company in the past 24 months; century: Current equity holder in publicly-traded company; ichnos biosciences: Consultancy, Current holder of stock options in a privately-held company.

The purpose of this study is to evaluate the safety, pharmacokinetics, pharmacodynamics, and activity of acalabrutinib in treating subjects with WM.

Study of the combination of acalabrutinib (ACP-196) and pembrolizumab in subjects with advanced head and neck squamous cell carcinoma.

This systematic literature review (CRD42023393903) and a Bayesian network meta-analysis (NMA) aimed to assess the relative safety profile of first-line targeted therapies (acalabrutinib, ibrutinib, obinutuzumab, ofatumumab, pirtobrutinib, ublituximab, umbralisib, venetoclax, zanubrutinib) in chronic lymphocytic leukaemia (CLL) patients with advanced age and/or comorbidities. The NMA revealed that zanubrutinib was the safest treatment option in terms of the overall safety profile (e.g., serious adverse events [AEs] grade 1-5), followed by venetoclax-obinutuzumab, which showed an advantage in terms of AEs grade 1-5. The use of Bruton's tyrosine kinase inhibitor (BTKi) monotherapy was more favourable in terms of the risk of haematological AEs, but chemoimmunotherapy showed advantages in terms of cardiovascular, gastrointestinal, and infectious AEs. The risk of secondary cancers was similar between treatments. In conclusion, targeted therapies are associated with variable and clinically relevant AEs. The therapies appear to be safer when used as monotherapy rather than in combination with immunological agents in naïve CLL patients with advanced age and/or comorbidities.

To understand the incidence of ADRs of Calquence 100 mg capsules (acalabrutinib) used in patients with relapsed or refractory chronic lymphocytic leukaemia (including small lymphocytic lymphoma) in a real-world post-marketing setting

Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is a type of mature B lymphocyte clonal proliferative tumor with a specific immunophenotype. Bruton tyrosine kinase inhibitors (BTKi) have been approved for the treatment of CLL/SLL. However, the efficacy and safety of new-generation BTKi-based regimens have not been systematically studied. In this systematic review, we evaluated the efficacy and safety of new-generation BTKi-based regimens for the treatment of patients with CLL/SLL. A comprehensive search on PubMed, Embase, Cochrane Library, and ClinicalTrials.gov. up to January 31, 2023, was conducted by us. Studies reporting data on CLL/SLL patients treated with new-generation BTKi were included. We assessed the overall response rate (ORR), complete response (CR) rate, and 24-month OS/PFS rates for efficacy analysis. For safety analysis, we evaluated the incidence of grade ≥ 3 adverse events (AEs). The meta-analysis included twenty studies. The pooled ORR for new-generation BTKi was 92% (95% CI, 89–95%, I2 = 80.68%, P = 0.00), while the pooled CR rate was 10% (95% CI, 6–14%, I2 = 88.11%, P = 0.00). Research has found that the new-generation BTKi-based therapy had higher efficacy under the following treatment conditions: < 65 years old, treatment-naive (TN)-CLL, and BTKi combination therapy. The ORR/CR rates and 24-month OS/PFS rates of BTKi combination therapy were higher than that of BTKi monotherapy. Compared to acalabrutinib monotherapy, zanubrutinib monotherapy demonstrated higher ORR/CR rates and 24-month OS/PFS rates. Common grade ≥ 3 AEs included cytopenia and hypertension. The new-generation BTKi-based therapy has good tolerance and provides incremental benefits for CLL/SLL patients. Despite the superior efficacy of BTKi combination therapy compared to monotherapy, its AEs rates are relatively high. Compared to acalabrutinib, Zanubrutinib may be the preferred monotherapy for CLL. However, randomized-controlled studies are still needed.

This is a multicenter, prospective, observational cohort study to comprehensively and longitudinally evaluate and characterizes the cardiovascular events with CLL patients who are initiating treatment with a Bruton\'s tyrosine kinase (BTK) inhibitor ibrutinib or acalabrutinib.