Phase 1 Trial of BTM-3566 in Relapsed/Refractory Mature B Cell Lymphomas

The goal of this clinical trial is to learn if BMT-3566 can safety be given to adult patients with relapsed or refractory mature b cell lymphomas. It will also learn how well BTM-3566 works to treat relapsed or refractory mature b cell lymphomas. The main questions it aims to answer are: What are the side effects of BTM-3566 at different doses? What are the levels of BTM-3566 in the blood at different timepoints around dosing? What is the clinical benefit of BTM-3566 in treating cancer (i.e. how well does it slow or stop disease progression)? Participants will: Take BTM-3566 in 14-day periods with 7 days of dosing followed by 7 days of no dosing Visit the clinic regularly for checkups and tests Keep a diary of their dosing and weight

Inclusion Criteria: * must be age ≥18 years * must have a diagnosis of relapsed or refractory mature B cell lymphoma * must have measurable disease per response evaluation criteria in lymphoma (Lugano classification) * must have an Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0-2 * must have a predicted life expectancy of ≥3 months * must agree to use adequate birth control throughout their participation and for 90 days following the last dose of BTM-3566 Exclusion Criteria: * has primary CNS lymphoma * has ongoing toxicities from prior anti-cancer treatment \> Grade 1 * has symptomatic or uncontrolled neurologic disease (brain metastases, leptomeningeal disease, or spinal cord compression) not definitively treated with surgery or radiation * has received any anti-cancer therapy (including radiation of curative intent) \