Comparison of the Treatments of Obinutuzumab + Venetoclax Versus Obinutuzumab + Chlorambucil in Patients With Chronic Lymphocytic Leukemia

Inclusion Criteria: * Documented previously untreated CLL according to the International Workshop on Chronic Lymphocytic Leukemia (IWCLL) criteria * CLL requiring treatment according to IWCLL criteria * Total Cumulative Illness Rating Scale (CIRS score) greater than (\>) 6 * Adequate marrow function independent of growth factor or transfusion support within 2 weeks of screening as per protocol, unless cytopenia is due to marrow involvement of CLL * Adequate liver function * Life expectancy \> 6 months * Agreement to use highly effective contraceptive methods per protocol Exclusion Criteria: * Transformation of CLL to aggressive Non-Hodgkin's lymphoma (Richter's transformation or pro-lymphocytic leukemia) * Known central nervous system involvement * Participants with a history of confirmed progressive multifocal leukoencephalopathy (PML) * An individual organ/ system impairment score of 4 as assessed by the CIRS definition limiting the ability to receive the treatment regimen of this trial with the exception of eyes, ears, nose, throat organ system * Participants with uncontrolled autoimmune hemolytic anemia or immune thrombocytopenia * Inadequate renal function * History of prior malignancy, except for conditions as listed in the protocol if participants have recovered from the acute side effects incurred as a result of previous therapy * Use of investigational agents or concurrent anti-cancer treatment within the last 4 weeks of registration * Participants with active bac…