Phase II Study of Combined Pirtobrutinib, Venetoclax and Obinutuzumab (PVO) Time-limited Treatment for Patients With Recurrent Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL).

Primary Objective:

\- Rate of bone marrow undetectable Measurable Residual Disease (10-4 sensitivity; uMRD4) at end of Cycle 13.

Secondary Objectives:

* Blood uMRD6 rate at end of cycles 9, 13, 19, 25. * 2018 iwCLL response rates defined as complete response (CR), CR with incomplete count recovery (CRi), partial response (PR), overall response (OR), stable disease (SD), and progressive disease (PD) at cycle 13. * Progression-free (PFS) and overall survival (OS); time to blood uMRD6 relapse; safety and tolerability.