Uncontrolled autoimmune hemolytic anemia or thrombocytopenia. History of autoimmune hemolytic anemia or autoimmune thrombocytopenia. Untreated autoimmunity such as autoimmune hemolytic anemia, or immune thrombocytopenia Uncontrolled autoimmune hemolytic anemia or thrombocytopenia Uncontrolled autoimmune hemolytic anemia (AIHA) or idiopathic thrombocytopenia purpura (ITP) Uncontrolled autoimmune hemolytic anemia or thrombocytopenia Active and uncontrolled autoimmune hemolytic anemia (AIHA) or autoimmune thrombocytopenia (ITP) requiring daily prednisone dose of >= 20 mg. Patients should not have active or uncontrolled autoimmune hemolytic anemia or immune thrombocytopenia Active, uncontrolled autoimmune phenomenon (autoimmune hemolytic anemia or immune thrombocytopenia) requiring steroid therapy > 20 mg prednisone daily or equivalent, within 7 days of starting venetoclax Active, uncontrolled autoimmune hemolytic anemia or immune thrombocytopenia requiring steroid therapy Active, uncontrolled autoimmune phenomenon (autoimmune hemolytic anemia or immune thrombocytopenia) requiring steroid therapy with > 20 mg daily of prednisone dose or equivalent Active, uncontrolled autoimmune phenomenon (autoimmune hemolytic anemia or immune thrombocytopenia) requiring steroid therapy Active autoimmune disorder (with the exception of autoimmune hemolytic anemia or ITP) Active, uncontrolled autoimmune hemolytic anemia or immune thrombocytopenia requiring steroid therapy Autoimmune anemia and/or thrombocytopenia poorly responsive to corticosteroids or other standard therapy Patients who exhibit any active or on-going autoimmune processes including, but not limited to, autoimmune hemolytic anemia or immune thrombocytopenia purpura, are NOT eligible for participation Patients with uncontrolled Autoimmune Hemolytic Anemia (AIHA) or autoimmune thrombocytopenia (ITP). Patients with active autoimmune anemia or autoimmune thrombocytopenia are NOT eligible Autoimmune hemolytic anemia (AIHA) or idiopathic thrombocytopenia purpura (ITP) that is uncontrolled or requires >20 mg daily (QD) of prednisone (or equivalent) to maintain hemoglobin >8.0 g/dL or platelets >10,000 ?L without transfusion support Uncontrolled autoimmune hemolytic anemia or thrombocytopenia Uncontrolled autoimmune hemolytic anemia (Hgb < 11g/deciliter) or idiopathic thrombocytopenic purpura (< 100,000/µl) Uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenic purpura (ITP) resulting in (or as evidenced by) declining platelet or hemoglobin (Hgb) levels within the 4 weeks prior to first dose of study drug Autoimmune anemia or thrombocytopenia that is poorly responsive to corticosteroids Uncontrolled autoimmune hemolytic anemia or immune thrombocytopenic purpura (ITP) resulting in (or as evidenced by) declining platelet or hemoglobin (Hgb) levels within the 4 weeks prior to first dose of study drug Uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenia purpura. Uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenia purpura. Autoimmune anemia and/or thrombocytopenia that is poorly responsive to corticosteroids or other standard therapy. Patients with active or uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenic purpura (ITP) are excluded; patients who have transfusion-dependent thrombocytopenia or bleeding/coagulation disorders that may increase the risk of life-threatening bleeding are excluded Uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenic purpura (ITP) resulting in (or as evidenced by) declining platelet or hemoglobin (Hgb) levels within the 4 weeks prior to first dose of study drug Patients with uncontrolled autoimmune hemolytic anemia (AIHA) or autoimmune thrombocytopenia (ITP) Uncontrolled autoimmune hemolytic anemia or thrombocytopenia History of autoimmune hemolytic anemia or autoimmune thrombocytopenia. Autoimmune disease with the exception of controlled/treated hypothyroidism, disease-related immune thrombocytopenic purpura, or hemolytic anemia Untreated autoimmunity such as autoimmune hemolytic anemia, or immune thrombocytopenia Autoimmune disease related to CLL, e.g., idiopathic thrombocytopenic purpura (ITP) or autoimmune hemolytic anemia, is permitted if not requiring active treatment Active, uncontrolled autoimmune hemolytic anemia or immune thrombocytopenia requiring steroid therapy Uncontrolled autoimmune hemolytic anemia or thrombocytopenia Participants with uncontrolled autoimmune hemolytic anemia or immune thrombocytopenia Subjects with uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenic purpura (ITP) resulting in declining platelet or hemoglobin levels within the 4 weeks prior to first dose of study drug are not eligible Uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenia purpura. Uncontrolled autoimmune hemolytic anemia (AIHA) or idiopathic thrombocytopenia purpura (ITP) that is uncontrolled or requiring > 20 mg once daily (QD) of prednisone (or equivalent) to maintain hemoglobin > 8.0 g/dL or platelets > 10,000 ?L without transfusion support Active, uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenic purpura (ITP) Uncontrolled autoimmune hemolytic anemia or thrombocytopenia Patients with uncontrolled autoimmune hemolytic anemia or autoimmune thrombocytopenia Uncontrolled autoimmune hemolytic anemia (AIHA) or immune thrombocytopenia purpura (ITP) Patients with uncontrolled autoimmune hemolytic anemia (AIHA) or autoimmune thrombocytopenia (ITP) Uncontrolled autoimmune hemolytic anemia or thrombocytopenia Uncontrolled autoimmune hemolytic anemia or thrombocytopenia Uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenic purpura (ITP) resulting in (or as evidenced by) declining platelet or hemoglobin (Hgb) levels within the 4 weeks prior to first dose of study drug Uncontrolled autoimmune anemia or thrombocytopenia Suffering from an autoimmune disease (including refractory immune thrombocytopenia-ITP or refractory autoimmune hemolytic anemia-AIHA) Patients with autoimmune hemolytic anemia or autoimmune thrombocytopenia will be eligible for treatment Has autoimmune cytopenia (anemia, thrombocytopenia, leukopenia). Uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenic purpura (ITP) resulting in (or as evidenced by) declining platelet or hemoglobin (Hgb) levels within the 4 weeks prior to first dose of study drug total bilirubin ?1.5 X institutional ULN unless due to Gilbert's syndrome, controlled autoimmune hemolytic anemia or immune thrombocytopenia Active autoimmune hemolytic anaemia (AIHA) and idiopathic thrombocytopenic purpura (ITP) requiring corticosteroid therapy greater than 25 mg prednisone (or equivalent) or chemotherapy. Known active, uncontrolled autoimmune hemolytic anemia or immune thrombocytopenia requiring steroid therapy Active, uncontrolled autoimmune phenomenon autoimmune hemolytic anemia, idiopathic thrombocytopenic purpura (AIHA, ITP) requiring steroid therapy Subjects with Gilbert's syndrome or resolving autoimmune hemolytic anemia may have a bilirubin up to 3.0 x ULN and are still eligible Uncontrolled autoimmune hemolytic anemia (AIHA) or idiopathic thrombocytopenia purpura (ITP)