Can immunotherapy help people with advanced mesothelioma live longer? Five-year results show it can.

For people diagnosed with advanced pleural mesothelioma, a cancer of the lining of the lungs that can't be removed by surgery, the question has been whether a newer type of treatment called immunotherapy offers lasting help. This five-year follow-up from a major clinical trial provides an answer. The treatment, a combination of the immunotherapy drugs nivolumab and ipilimumab, continues to show a survival benefit compared to standard chemotherapy. After a median follow-up of over five and a half years, 14% of patients on the immunotherapy combination were alive at five years, compared to 6% of those who started on chemotherapy. This benefit was seen regardless of the specific type of mesothelioma tumor. The study also looked at a potential biomarker—a sign in the blood that might predict who benefits most. They found that patients with lower levels of a certain immune cell type (called M-MDSCs) before treatment tended to do better on the immunotherapy combination. Importantly, the survival advantage for the immunotherapy-first group remained even after the researchers accounted for the fact that nearly a quarter of patients in the chemotherapy group later received immunotherapy. No new safety concerns emerged with longer follow-up. These results confirm that the immunotherapy combination provides a durable, long-term benefit for some patients with this challenging cancer.