Treatment patterns and outcomes among mantle cell lymphoma patients treated with ibrutinib in the United States: a retrospective electronic medical record database and chart review study

Real-World Treatment Patterns, Survival, and Economic Burden Among Elderly MCL Patients Previously Treated With cBTKis

BACKGROUND

While covalent Bruton's tyrosine kinase inhibitors (cBTKis) have become a standard of care treatment for relapsed/refractory mantle cell lymphoma (R/R MCL), response duration is limited and resistance to BTKi and/or adverse events develop in a subset of patients. However, little real-world evidence on post-cBTKi clinical and economic outcomes exists for these patients.

PATIENTS AND METHODS

This retrospective study used 2010 to 2019 U.S. Medicare claims, to identify elderly (≥ 66 years) patients with newly-diagnosed MCL who received third-line (3L) treatment and had evidence of cBTKi use in a prior line of therapy. Outcomes were assessed ≥ 12-months post 3L-treatment initiation and included treatment patterns, all-cause and MCL-related HRU and costs, and overall survival.

RESULTS

The final sample contained 230 elderly patients with R/R MCL receiving 3L treatment who had cBTKi use in a prior line of therapy (mean age 75.0, 21.7% age > 80 years; 67.4% male; 93.9% White). Common 3L treatments included chemotherapy (26.1%), lenalidomide (18.7%), and bortezomib (18.3%); 1-quarter (25.7%) of patients received a cBTKi (17.8% ibrutinib; 7.8% acalabrutinib). Overall survival was poor from 3L treatment initiation (median OS = 9.4 months; 1-years survival rate = 43.7%). Patients exhibited high rates of HRU (73.6% experienced hospitalization) and substantial costs ($145,726) in the 12-months after 3L initiation.

CONCLUSION

A large unmet need exists in this patient subpopulation, highlighting the importance of ongoing development of novel therapeutics.

Real-World Evidence of Relapsed/Refractory Mantle Cell Lymphoma Patients and Treatments: A Systematic Review

Introduction

Mantle cell lymphoma (MCL) is an incurable disease with an aggressive clinical course, and most patients eventually relapse after chemotherapy. Targeted therapies developed for relapsed/refractory MCL have been approved based on clinical trial data. However, real-world setting data are scarce and scattered.

Areas Covered

This systematic review aimed to collect, synthesize, and describe the characteristics and treatment outcomes of patients with relapsed/refractory MCL after receiving a second or subsequent line of therapy in the real-world setting.

Expert Opinion

R/R MCL is clinically and biologically heterogeneous and still represents a therapeutic challenge, with high-risk and early relapsed patients remaining an unmet medical need. This systematic review is limited by the quality of the available data and the difficulty of comparing outcomes in R/R MCL due to the heterogeneity of the disease, but the results suggest that covalent BTKis should be positioned as second-line therapy, followed by CAR T-cells in BTK-i-relapsed patients. Chemo-free and combination therapies with established chemoimmunotherapy backbones in the relapsed and front-line settings have been recently developed, and front-line options are being improved to move targeted and cellular therapies to earlier lines, including front-line therapy, in elderly and younger fit patients. In the upcoming years, many new targeted agents will play an important role and will be incorporated to the routine practice as their sequence, and outcomes in unselected patients are determined.

Real-world analysis of adverse event rates after initiation of ibrutinib among Medicare beneficiaries with chronic lymphocytic leukemia

BACKGROUND

The first-generation BTK inhibitor ibrutinib is a standard-of-care therapy in the treatment of chronic lymphocytic leukemia (CLL) despite potential side effects that often lead to discontinuation.

METHODS

This study used 2013-2019 claims data to describe the incidence rate of adverse events (AEs) among elderly Medicare beneficiaries newly initiating ibrutinib for CLL.

RESULTS

The final sample contained 11,870 Medicare beneficiaries with CLL (mean age 77.2) newly initiating ibrutinib, of whom 65.2% discontinued over mean follow-up of 2.3 years. The overall incidence rate of AEs was 62.5 per 1000 patient-months for all discontinuers and 32.9 per 1000 patient-months for non-discontinuers. Discontinuers had a higher incidence rate of AEs per 1000 patient-months compared with non-discontinuers for all AEs examined, including infection (22.8 vs. 14.5), atrial fibrillation (15.1 vs. 7.0), anemia (21.9 vs. 14.5), and arthralgia/myalgia (19.5 vs. 13.6).

CONCLUSION

In this first real-world study of a national sample of elderly US patients treated with ibrutinib, we found a clear unmet need for improved management of ibrutinib-related AEs and/or new treatments to improve real-world outcomes in patients with CLL.

Ibrutinib discontinuation and associated factors in a real-world national sample of elderly Medicare beneficiaries with chronic lymphocytic leukemia

Prior studies evaluating ibrutinib discontinuation are limited to clinical trials and selected medical centers and hence may not reflect real-world practice. This study used Medicare claims (2013-2019) to examine ibrutinib discontinuation and associated factors among elderly patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). Over a median follow-up of 2.1 years, two-thirds (65.2%) of the 11,870 new ibrutinib initiators were discontinued, with half (45.1%) of patients discontinuing within 12 months of initiation. Factors such as advanced age, lack of Part D low-income subsidy, evidence of prior CLL/SLL treatment, and cardiovascular comorbidities (e.g. atrial fibrillation) were associated with higher risk of discontinuation. Over a median of 1.2 years from discontinuation, 40% of discontinuers initiated another CLL/SLL treatment after ibrutinib discontinuation; 25% of patients restarted ibrutinib treatment at some point over follow-up. Our findings point to a large unmet need with the widely used BTKi ibrutinib and underscore the importance of ongoing development of efficacious and well-tolerated CLL/SLL therapies.

Assessing unmet need among elderly Medicare Beneficiaries with Mantle cell lymphoma: an analysis of treatment patterns, survival, healthcare resource utilization, and costs

Studies evaluating real-world outcomes and health care utilization for mantle cell lymphoma are limited. We utilized national Medicare claims (2009-2019) to examine treatment patterns, healthcare resource utilization, costs, and survival in 3664 elderly patients receiving 1 L treatment for MCL. Over a median follow-up of 2.8 years, 40.3% received at least 2 L treatment. The most common 1 L regimen was bendamustine-rituximab (50.1%), with increased use of BTKi-based regimens observed in 2 L (39.4%). Half (51.8%) of patients had an all-cause hospitalization within 12 months of initiating 1 L; hospitalization rates were higher in later lines. Healthcare costs were substantial and most costs (>80%) were MCL-related. Overall survival was poorer among later lines of treatment (median OS from initiation of 1 L: 53.5 months; 2 L: 22.0 months; 3 L: 11.8 months; 4 L: 7.8 months). These results suggest a large unmet need and future work should evaluate whether novel therapies have improved outcomes among elderly patients with MCL.

Australian experience with ibrutinib in patients with relapsed/refractory mantle cell lymphoma: a study from the Lymphoma and Related Diseases Registry

Bruton's tyrosine kinase inhibitors (BTKi) have an established role in the management of patients with relapsed/refractory mantle cell lymphoma (MCL). However, scant data exist on outcomes of patients ineligible for clinical trials testing these therapies. We describe a contemporary cohort of relapsed/refractory MCL patients from the Australasian Lymphoma and Related Diseases Registry treated with ibrutinib December 2014 until July 2018, to determine the proportion potentially eligible for original trials, reasons for ineligibility and survival outcomes. Of 44 patients, 41% met one or more exclusion criteria from previous phase II/III MCL BTKi studies. Median progression-free and overall survival were 13.7 months (95% CI 6.2-28.1) and 15.6 months (95% CI 10.8-29.6) respectively and were shorter in patients excluded from clinical trials based on ECOG ≥2. Ibrutinib has demonstrable clinical effectiveness in a population enriched for unfit and trial-ineligible patients, and a need for more inclusive enrollment criteria in future BTKi studies is highlighted.

BRUIN MCL-321: phase III study of pirtobrutinib versus investigator choice of BTK inhibitor in BTK inhibitor naive mantle cell lymphoma

Treatment with covalent Bruton tyrosine kinase inhibitors (BTKi) represents an important advance in the management of relapsed or refractory mantle cell lymphoma, but these treatments are not curative and many patients ultimately relapse. Pirtobrutinib, a highly selective, noncovalent (reversible) BTKi, inhibits both wild type and C481-mutant BTK with equal low nM potency, and has favorable oral pharmacology that enables continuous BTK inhibition throughout the dosing interval regardless of intrinsic rate of BTK turnover. Pirtobrutinib is well tolerated and has demonstrated promising efficacy in patients with poor prognosis B-cell malignancies following prior therapy, including covalent BTKi. This phase III, head-to-head, randomized study (NCT04662255) will evaluate whether pirtobrutinib is superior to investigator's choice of covalent BTKi in patients with previously treated, BTKi-naive mantle cell lymphoma.

Mantle cell lymphoma treatment options for elderly/unfit patients: A systematic review

Mantle cell lymphoma (MCL) is a rare B-cell non-Hodgkin lymphoma (NHL) that is aggressive and incurable with existing therapies, presenting a significant unmet clinical need. MCL occurs mainly in elderly patients with comorbidities; thus, intense treatment options including allogeneic stem cell transplantation (Allo-SCT) are not feasible. New treatment options are emerging for this elderly/unfit treatment group, we therefore conducted a systematic review to determine whether they offered an advance on the existing recommended treatment, R-CHOP. The search strategies to identify MCL therapies were designed to capture the most relevant studies from 2013 to 2020. Following preferred reporting items for systematic reviews and meta-analyses and population,interventions, observations and study design analysis, R-CHOP, ibrutinib and bendamustine plus rituximab (BR) were taken forward for critical and statistical analysis. All three therapies were effective in increasing the overall survival (OS) and progression-free survival of elderly/unfit patients with MCL. However, none resulted in a significant increase in OS compared to R-CHOP. In addition, R-CHOP had a better toxicity profile when compared to both ibrutinib and BR. We therefore conclude that treatment of elderly/unfit patients with MCL is still a significant unmet clinical need; and suggest that outside of the clinical trial setting, R-CHOP should remain the recommended front-line treatment for this patient group.

Outcomes for Recurrent Mantle Cell Lymphoma Post-Ibrutinib Therapy: A Retrospective Cohort Study from a Japanese Administrative Database

INTRODUCTION

Treatment options in patients with mantle cell lymphoma (MCL) failing ibrutinib are limited, with no standard therapies defined. This study aimed to investigate real-world treatment patterns and outcomes for patients with MCL following ibrutinib.

METHODS

This study utilized a de-identified hospital-based claims database (Medical Data Vision) in Japan. Eligible patients were adults who were diagnosed with MCL and had received antitumor drugs between December 2010 and July 2020. Patients were followed from the first antitumor drug treatment until the end of available data up to July 2021. Time-to-event analyses utilized the Kaplan-Meier method. Factors for receiving post-ibrutinib therapy were explored with logistic regression analysis.

RESULTS

Of the 1386 patients who started antitumor drug therapy, 247 patients received and discontinued ibrutinib at any line of therapy. Among them, 137 patients (55.5%) received subsequent therapy. The median age at the end of ibrutinib therapy was 77 (range 42-95), and 44 patients had a dependent activity of daily living (ADL). Factors negatively associated with receiving post-ibrutinib therapy after discontinuation of ibrutinib were age ≥ 75 years (odds ratio [95% CI] 0.46 [0.26-0.80]) and emergency hospital admissions (0.37 [0.17-0.84]). Immediate post-ibrutinib therapy regimens were highly diverse, with BR (bendamustine, rituximab) only prescribed in more than 10% of patients. The median duration of post-ibrutinib therapy was 1.5 months (95% CI 1.07-2.07). The median overall survival from the end of ibrutinib therapy in patients regardless of the receipt of post-ibrutinib therapy (n = 247), in those who did not receive post-ibrutinib therapy (n = 110), and in those who received post-ibrutinib therapy (n = 137) was 5.6 months (95% CI 3.8-8.7), 2.3 months (95% CI 1.2-3.9), and 8.7 months (95% CI 5.6-13.8), respectively. The most common adverse event during post-ibrutinib therapy was infection, with the use of anti-infectives (17%).

CONCLUSIONS

Patients with MCL previously treated with ibrutinib have poor ability to carry out ADL and experience very poor outcomes. New safe, effective therapies are needed.

Safety Profile of Ibrutinib: An Analysis of the WHO Pharmacovigilance Database

As ibrutinib has become a standard of care in B-cell malignancies in monotherapy or in combination with other agents, definition of its safety profile appears essential. The aim of this study was to further characterize the safety profile of ibrutinib through the identification of potential safety signals in a large-scale pharmacovigilance database. All serious individual case safety reports (ICSRs) in patients aged ≥18 years involving ibrutinib suspected in the occurrence of serious adverse drug reactions or drug interacting from November 13th, 2013 to December 31st, 2020 were extracted from VigiBase, the World Health Organization global safety database. Disproportionality reporting was assessed using the information component (IC) and the proportional reporting ratio (PRR), with all other anticancer drugs used as the reference group. To mitigate the confounding of age, two subgroups were considered: patients aged<75 years and ≥75 years. A signal of disproportionate reporting (SDR) was defined if both IC and PRR were significant. A total of 16,196 ICSRs were included. The median age of patients was 72.9 years, 42.6% of ICSRs concerned patients aged ≥75 years, and 64.2% male patients. More than half (56.2%) of ICSRs resulted in hospitalization or prolonged hospitalization. Among 713 SDRs, 36 potential safety signals emerged in ibrutinib-treated patients, mainly ischemic heart diseases, pericarditis, uveitis, retinal disorders and fractures. All potential safety signals having arisen in this analysis may support patient care and monitoring of ongoing clinical trials. However, owing to the mandatory limitations of this study, our results need further confirmation using population-based studies.