A drug used to treat diffuse large B-cell lymphoma that relapsed (came back) or did not get better after treatment with at least two other types of anticancer therapy. Tisagenlecleucel is also used to treat B-cell acute lymphoblastic leukemia (ALL) in patients aged 25 years and younger. It is used in patients whose cancer has not gotten better with other treatment or has relapsed two or more times. It is also being studied in the treatment of other types of cancer. Tisagenlecleucel is made using a patient’s T cells (a type of immune system cell). A gene for a special receptor called chimeric antigen receptor (CAR) is added to the T cells in the laboratory. These changed T cells called CAR T cells are grown in large numbers in the laboratory and given to the patient by infusion. Tisagenlecleucel binds to a protein called CD19, which is found on some leukemia and lymphoma cells. This helps the body’s immune system kill cancer cells. Tisagenlecleucel is a type of CAR T-cell therapy. Also called Kymriah.