Autologous B7-H3 CAR T

Background: Small cell lung cancer (SCLC) is the deadliest form of lung cancer. Extrapulmonary neuroendocrine cancer (EPNEC) is a similar type of cancer that develops anywhere other than the lungs. EPNEC is also deadly. B7-H3 is a protein often found in SCLC and EPNEC tumor cells. Researchers can modify a person s own T cells, or immune cells, to target B7-H3. When these modified T cells are returned to the body-a treatment called B7-H3 chimeric antigen receptor (CAR) T cell therapy-they may help kill cancer cells. Objective: To test B7-H3 CAR T cell therapy in people with SCLC or EPNEC. Eligibility: People aged 18 years and older with SCLC or EPNEC that either did not respond or returned after treatment. Design: Participants will be screened. They will have blood tests and tests of their heart function. They will have imaging scans. Participants will undergo apheresis: Blood will be taken from the body through a needle. The blood will pass through a machine that separates out the T cells. The remaining blood will be returned to the body through a different needle. The collected T cells will be altered to make them attack cells with B7-H3. Participants will be in the hospital for at least 15 days. They will receive chemotherapy drugs to prepare their body for the treatment. These drugs will be given through a tube attached to a needle inserted into a vein. The modified T cells will be infused through a vein. Participants will remain in the hospital until they are well enough to go home. Follow-up visits will continue for 15 years....