Background: Multiple studies have demonstrated the efficacy and safety of ibrutinib for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and mantle cell lymphoma (MCL). This first-in-class inhibitor of Bruton's tyrosine kinase has become a standard treatment for patients with CLL and MCL.
Patients and methods: We conducted an integrated safety analysis to characterize the frequency, severity, natural history, and outcomes of adverse events (AEs) with ibrutinib versus comparators. Data were pooled from 4 completed randomized controlled studies that had included 756 ibrutinib-treated and 749 comparator-treated patients with CLL/SLL or relapsed/refractory MCL. Safety analyses included reporting of AEs using crude and exposure-adjusted incidence rates.
Results: The median treatment duration was 13.3 months (maximum, 28.2 months) for ibrutinib and 5.8 months (maximum, 27.3 months) for comparators. When adjusted for exposure, diarrhea, atrial fibrillation, and hypertension were the only common grade ≥ 3 AEs more often reported with ibrutinib than with the comparators. Dose reductions (7% vs. 14%) and discontinuation (12% vs. 16%) because of AEs occurred less often with ibrutinib, and deaths due to AEs occurred at similar rates (6% vs. 7%). When adjusted for exposure, the corresponding data were all lower with ibrutinib than with the comparators (0.06 vs. 0.22, 0.11 vs. 0.22, and 0.06 vs. 0.09 patient-exposure-years, respectively). The prevalence of common grade 3/4 AEs with ibrutinib generally decreased over time, with the exception of hypertension.
Conclusion: These results from an integrated analysis support a favorable benefit/risk profile of ibrutinib in patients with CLL/SLL and MCL.
Keywords: Adverse events; Benefit/risk profile; Bruton's tyrosine kinase inhibitor; Exposure-adjusted incidence rate; Pooled analysis.
Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.