Lymphoplasmacytic Lymphoma/Waldenström Macroglobulinemia

This Phase 1, open-label, multicenter study is evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of lonitoclax (ZE50-0134) in adults with relapsed or refractory chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL), and select low-grade B-cell lymphomas. The study has two sequential parts. Part 1 uses dose escalation to determine the biologically effective dose and/or maximum tolerated dose of lonitoclax. Participants receive a 3-day step-up regimen followed by continuous once-daily or twice-daily oral dosing in 28-day cycles. Part 2 is a randomized dose-expansion comparison of two selected lonitoclax dose levels in venetoclax-naive participants with relapsed or refractory CLL/SLL. Treatment may continue for up to 12 cycles and, for participants deriving clinical benefit, for up to 24 cycles with approval from the Medical Monitor.