Safety Study of CC312 in Adult Patients With Relapsed/Refractory CD19 Positive B-cell Hematologic Malignancies

This study is testing the safety of a new drug called CC312 in patients with certain blood cancers (B-cell cancers like B-cell lymphoma, leukemia, or chronic lymphocytic leukemia) that have returned or stopped responding to prior treatment. **You may be eligible if...** - You have a confirmed CD19-positive B-cell blood cancer (such as B-cell lymphoma, leukemia, or CLL) - Your cancer has relapsed (come back) or is no longer responding to standard treatments - You are in reasonably good health and your liver and kidney function are within acceptable ranges - Your life expectancy is more than 3 months **You may NOT be eligible if...** - Your liver or kidney function is significantly impaired - You have uncontrolled infections or serious other illnesses - You have active brain metastases - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.