Treatment of Patients With Relapsed or Refractory CD19+ Lymphoid Disease With T Cells Expressing a Third-generation CAR

This trial is testing a third-generation CAR T-cell therapy — where a patient's own immune cells are genetically reprogrammed to hunt and destroy a protein called CD19 found on certain blood cancer cells — for people whose blood cancer has come back or stopped responding to treatment. **You may be eligible if...** - You are 18 years or older with a confirmed CD19-positive blood cancer: this includes acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), or mantle cell lymphoma (MCL) - Your cancer has relapsed (come back) or is refractory (not responding) to prior treatment - You are in adequate health to receive the therapy - You have confirmed CD19 expression on your cancer cells **You may NOT be eligible if...** - Your cancer involves the brain or spinal fluid (CNS disease) - You have serious organ problems (heart, liver, or kidneys) - You have active severe infections - You are pregnant or breastfeeding - You have previously received CAR T-cell therapy targeting CD19 and are ineligible for retreatment Talk to your doctor to see if this trial is right for you.