A Study to Investigate the Safety of Novel Dose Ramp-up Schedule(s) When Initiating Sonrotoclax in Participants Treated for Blood Cancers.

This study will test the safety of novel sonrotoclax dosing with gradual increases of sonrotoclax dose over specified periods until the intended target daily dose is reached. The focus will be on tumor lysis syndrome (TLS) and related toxicity signals. Sonrotoclax is a drug that works by blocking a protein called B-cell lymphoma-2 (BCL-2). When sonrotoclax blocks BCL-2 it slows down or stops the growth of tumor cells and helps them die. This can lead to improvements in patients with certain malignant diseases including chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL). The start of treatment with BCL-2 inhibitor requires a gradual ramp-up over the first weeks to avoid potential consequences of initial tumor cell breakage and the release of cell content in the bloodstream. Several ramp-up schedules have already been explored, and this study aims to optimize the dosing ramp-up schedule that may be beneficial to patients and caregivers. Zanubrutinib is a commercialized product that works by blocking a protein called Bruton's tyrosine kinase (BTK) and controlling the activity and survival of malignant B cells. Zanubrutinib has received approval in over 65 countries/regions worldwide for the treatment of adult participants with B-cell malignancies, including CLL and MCL. This study will take place at multiple centers worldwide. The overall time to participate in this study is approximately 17 months for treatment-naïve (TN) CLL participants or approximately 32 months for relapsed/refractory (R/R) MCL participants.