For decades, researchers have been exploring ways to harness the power of the immune system to treat cancer. One breakthrough is cell therapy, often called 'living drugs.' This is a form of immunotherapy that uses immune cells from a patient or a healthy donor. With advanced engineering techniques, scientists enhance these cells to recognize better and attack cancer.

“During the late 1980s and 1990s, cancer researchers started exploring ways to advance immunotherapy by transferring immune cells into a patient to attack cancer cells,” says stem cell transplant and cellular therapy specialist Hind Rafei, M.D. “They recognized that immune cells found inside tumors could help destroy cancer cells, leading to the development of one of the earliest forms of cell therapy — tumor-infiltrating lymphocytes (TILs).”

Currently approved types of cell therapy

There are currently three types of cell therapy that have been approved to treat certain cancers by the Food and Drug Administration (FDA).

Tumor-Infiltrating Lymphocyte (TIL) therapy

TIL therapy is one of the earliest forms of cell therapy. It involves extracting immune cells from a patient’s tumor, growing them and enhancing them outside the body with small proteins called cytokines. Once reinfused into the patient, the goal is for them to expand rapidly and attack cancer cells. TIL therapy is primarily used to treat solid tumors, particularly melanomas. In 2024, the Food and Drug Administration (FDA) approved the first TIL therapy, marking a significant milestone in cancer treatment.

T cell receptor (TCR) cell therapy

T cells are collected from a patient and genetically modified to detect specific protein fragments, or peptides, displayed on the surface of cancer cells. These peptides are presented by molecules called human leukocyte antigens (HLAs), which act like a cellular ID card, helping the immune system distinguish between healthy and abnormal cells. Once infused back into the patient, the engineered T cells recognize these peptides, bind to the HLA molecules, and launch an attack on the cancer cells. The FDA approved the first TCR therapy in 2024 for synovial sarcoma, a rare soft-tissue cancer, marking a major advancement in precision cancer treatment.

Chimeric antigen receptor T cell therapy (CAR T cell therapy)

CAR T cell therapy has revolutionized cancer treatment in recent years. Unlike TCR therapy, which modifies T cells to recognize specific peptides presented by each patient’s unique cellular ID cards called HLA molecules, CAR T cell therapy engineers T cells to directly bind to cancer cell surface proteins. This means it can be used to treat far more patients. “With CAR T cell therapy, we can precisely and powerfully target cancer cells through these CARs,” Rafei says. Since 2017, seven CAR T cell therapies have been approved by the FDA for some blood cancers such as multiple myeloma, large B-cell lymphoma, and mantle cell lymphoma. Many of these approvals have been based on clinical trials led by MD Anderson researchers.