A Study of Nemtabrutinib vs Chemoimmunotherapy for Participants With Previously Untreated Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL) Without TP53 Aberrations (MK-1026-008, BELLWAVE-008)

The purpose of this study is to evaluate the efficacy and safety of nemtabrutinib compared to investigator's choice of fludarabine plus cyclophosphamide plus rituximab (FCR) or bendamustine plus rituximab (BR) in participants with previously untreated CLL/SLL without 17p deletion and/or tumor protein (TP) 53 mutation. The primary hypothesis is that nemtabrutinib is superior to FCR/BR with respect to progression-free survival (PFS).

The main inclusion and exclusion criteria include but are not limited to the following:Inclusion Criteria:Confirmed diagnosis of CLL/SLL and active disease clearly documented to have a need to initiate therapy.Has previously untreated CLL/SLL without TP53 aberrations. Prior palliative radiation therapy administered locally is permitted.The ability to swallow and retain oral medication.Exclusion Criteria:Active hepatitis B virus (HBV) or hepatitis C virus (HCV) infection.Gastrointestinal dysfunction that may affect drug absorption (eg, gastric bypass surgery, gastrectomy).Known additional malignancy that is progressing or has required active treatment within the past 3 years, except basal cell carcinoma of skin, squamous cell carcinoma of skin, or carcinoma in situ (eg, breast carcinoma, cervical cancer in situ) that have undergone potential curative therapy.History of severe bleeding disorders.Not adequately recovered from major surgery or has ongoing surgical complications.