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.
Can immunotherapy help people with advanced mesothelioma live longer? Five-year results show it can.
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A two-drug immunotherapy combo provides lasting survival benefit over chemo for advanced mesothelioma, even after five years. What this means for you:
A two-drug immunotherapy combo provides lasting survival benefit over chemo for advanced mesothelioma, even after five years. View Original Abstract ↓
In this 5-year follow-up from the CheckMate 743 study in patients with unresectable pleural mesothelioma (PM), we evaluated updated efficacy and safety outcomes and biomarkers and performed treatment-switching analyses with first-line nivolumab plus ipilimumab versus chemotherapy. With a median follow-up of 66.8 months, nivolumab plus ipilimumab demonstrated continued overall survival (OS) benefit versus chemotherapy in all randomly assigned patients (5-year OS rates, 14% 6%; hazard ratio [HR], 0.74 [95% CI, 0.62 to 0.88]); similar benefit was observed regardless of tumor histology. Of biomarker-evaluable patients treated with nivolumab plus ipilimumab (n = 242), high baseline monocytic myeloid-derived suppressor cell (M-MDSC) levels correlated with worse OS versus low M-MDSC levels (HR, 1.25 [95% CI, 1.09 to 1.43]). After adjusting for 24% of patients in the chemotherapy arm who received subsequent immunotherapy, nivolumab plus ipilimumab demonstrated continued OS benefit versus chemotherapy (HR, 0.64 [95% CI, 0.53 to 0.78]). No new safety signals were observed. These results demonstrate long-term, durable clinical benefit with nivolumab plus ipilimumab versus chemotherapy, which continued to be preserved even after treatment-switching adjustment in the chemotherapy arm. Exploratory analyses suggested greater benefit with nivolumab plus ipilimumab in the low M-MDSC subgroup. These results further support first-line nivolumab plus ipilimumab as standard of care for unresectable PM.