First-Line Treatment with Ibrutinib (Ibr) Plus Venetoclax (Ven) for Chronic Lymphocytic Leukemia (CLL): 2-Year Post-Randomization Disease-Free Survival (DFS) Results from the Minimal Residual Disease (MRD) Cohort of the Phase 2 Captivate Study

Background: Ibr, an established standard of care in CLL, is a once-daily Bruton tyrosine kinase inhibitor with significant progression-free survival (PFS) and overall survival benefit shown in multiple randomized phase 3 studies in first-line CLL. Ven, an oral BCL-2 inhibitor approved as a single agent or combined with rituximab or obinutuzumab for CLL treatment, achieves high rates of undetectable MRD (uMRD). Ibr and Ven, with distinct and complementary mechanisms of action, work synergistically to mobilize CLL cells from lymph nodes and lymphoid niches, enhance cell killing, and eliminate distinct CLL cell populations. CAPTIVATE (PCYC-1142; NCT02910583) is an international, multicenter phase 2 study evaluating first-line Ibr + Ven in 2 cohorts: MRD and Fixed-Duration (FD). Patients (pts) first received 3 cycles of Ibr followed by 12 cycles of combined Ibr + Ven. In the primary analysis of the MRD cohort, pts with Confirmed uMRD who after fixed duration treatment were randomized to placebo or continued Ibr had similar post-randomization 1-year DFS rates (95% and 100%, respectively) (Wierda, ASH 2020). Two-year post-randomization results are presented.