Combination immunotherapy shrank a variety of metastatic gastrointestinal cancers

Tuesday, April 1, 2025

NIH trial shows new form of TIL therapy effective against colon, rectum, pancreas, and bile duct tumors

A new form of tumor infiltrating lymphocyte (TIL) therapy, a form of personalized cancer immunotherapy, dramatically improved the treatment’s effectiveness in patients with metastatic gastrointestinal cancers, according to results of a clinical trial led by researchers at the National Institutes of Health (NIH). The findings, published April 1, 2025 in Nature Medicine, offer hope that this therapy could be used to treat a variety of solid tumors, which has so far eluded researchers developing cell-based therapies.

This form of therapy involves identifying and selecting immune cells (TILs) that are found in the tumor that specifically recognize and attack a patient’s tumor cells. Next, scientists grow those TILs into large quantities in the laboratory before they are finally administered to the patient.

Patients in the clinical trial, who had a variety of gastrointestinal tumors, also received the immune checkpoint inhibitor pembrolizumab (Keytruda) to help further boost their immune response. The result was nearly 24 percent of patients treated with selected TILs plus pembrolizumab had a substantial reduction in the size of their tumors, compared with 7.7 percent of patients who received selected TILs without pembrolizumab. Patients treated with TILs that had not been selected for anti-tumor activity had no tumor shrinkage.

“We're seeing the first extension of cellular therapy with TILs into the common solid cancers,” said Steven A. Rosenberg, M.D., Ph.D., the study’s lead investigator at NIH’s National Cancer Institute. “We see a little crack in the solid wall of cancer by using cell-based immunotherapy for the common solid cancers, and we think we have ways to open that crack even further.”

*Image of an MRI scan showing shrinkage of multiple liver metastases from a patient with rectal cancer*