Phase 1 Study of Lonitoclax in Adults with Relapsed or Refractory Chronic Lymphocytic Leukemia, Small Lymphocytic Lymphoma, and Select Low-grade Lymphomas

What this Trial Is About

Researchers are evaluating lonitoclax ZE50-0134 in adults with relapsed or refractory chronic lymphocytic leukemia CLL, small lymphocytic lymphoma SLL, and certain low-grade B-cell lymphomas. This Phase 1, open-label, multicenter study aims to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and early antitumor effects of lonitoclax. The study includes two parts dose escalation to find the best dose and a randomized dose-expansion phase in venetoclax-naive participants with relapsed or refractory CLLSLL. Participants in Part 1 receive a 3-day step-up dosing regimen with inpatient monitoring and tumor lysis syndrome prevention, followed by continuous oral lonitoclax once or twice daily in 28-day cycles. Part 2 randomizes venetoclax-naive participants to one of two selected lonitoclax dose levels, continuing treatment for up to 12 cycles. Those benefiting clinically may continue for up to 24 cycles with medical approval. Throughout the study, participants undergo safety monitoring, including assessments of adverse events and dose-limiting toxicities. Researchers measure lonitoclax levels in the blood, response rates, duration of response, progression-free survival, and time to next treatment. Follow-up continues after treatment to track safety, disease progression, additional therapies, and survival, with total participation lasting as long as treatment continues and follow-up occurs.

A Study of Lonitoclax (ZE50-0134) in Relapsed or Refractory B-cell Malignancies