Pemetrexed plus platinum as second-line treatment for patients with pleural mesothelioma treated with nivolumab plus ipilimumab.

There is limited evidence regarding the second-line treatment for patients with unresectable, advanced, or metastatic pleural mesothelioma receiving first-line nivolumab plus ipilimumab combination immunotherapy. Although chemotherapy with pemetrexed and a platinum-based agent is empirically administered as the second-line treatment in clinical practice, its effect in patients after nivolumab plus ipilimumab remains unclear. Therefore, this retrospective observational study aimed to elucidate the efficacy of pemetrexed plus platinum therapy as a second-line treatment for pleural mesothelioma after first-line nivolumab-ipilimumab immunotherapy. Forty-three patients with unresectable or advanced pleural mesothelioma were enrolled in this study. Median overall survival was 17.1 months (95 % confidence interval [CI]: 9.3- not estimable), and median progression-free survival was 5.7 months (95 % CI: 3.9-11.9). The one-year overall survival rate was 62.8 % (95 % CI: 45.0-76.3) and one-year progression-free survival rate was 26.2 % (95 % CI: 10.4-45.2). In patients with measurable lesions, the overall response rate was 30.3 % and disease control rate was 69.7 %. These results are similar to those of previous studies on pemetrexed-platinum for pleural mesothelioma in first-line settings, suggesting that pemetrexed-platinum therapy can be considered an appropriate choice for the second-line treatment of mesothelioma after immunotherapy.