Tisagenlecleucel, marketed as Kymriah, is a treatment for B-cell acute lymphoblastic leukemia (ALL) which uses the body's own T cells to fight cancer (adoptive cell transfer). T cells from a person with cancer are removed, genetically engineered to make a specific chimeric cell surface receptor with components from both a T-cell receptor and an antibody specific to a protein on the cancer cell, and transferred back to the person. The T cells are engineered to target a protein called CD19 that is common on B cells. A chimeric T cell receptor ("CAR-T") is expressed on the surface of the T cell.

It was invented and initially developed at the University of Pennsylvania; Novartis completed development, obtained FDA approval, and markets the treatment. In August 2017, it became the first FDA-approved treatment that included a gene therapy step in the United States. In May 2018, the FDA further approved Kymriah to treat adults with relapsed or refractory diffuse large B-cell lymphoma. In June 2018, The European Medicines Agency (EMA) has recommended marketing authorization of Kymriah. On August 27, 2018, the European Commission has approved Kymriah for the treatment of pediatric and young adult patients up to 25 years of age with B-cell acute lymphoblastic leukemia (ALL) that is refractory, in relapse post-transplant or in second or later relapse; and for the treatment of adult patients with relapsed or refractory (r/r) diffuse large B-cell lymphoma (DLBCL) after two or more lines of systemic therapy.