 2. Any major surgery, radiotherapy, chemotherapy, biologic therapy, immunotherapy, experimental therapy within 4 weeks prior to the first dose of the study drugs. For oral targeted therapies such as ibrutinib, idelalisib, venetoclax, a washout of 3 days is allowed. Note: Prior treatment with anti CD20 monoclonal antibody, anti CD52 monoclonal antibody and lenalidomide are allowed. Prior treatment with anti-CTLA-4 and anti-PD1 therapies is allowed after a wash-out of 5 half-lives. 