Purpose: Neoadjuvant immune checkpoint blockade with nivolumab plus ipilimumab improves overall survival (OS) in non-small cell lung cancer (NSCLC); however, randomized data for resectable lung cancer are limited. We report results from the exploratory concurrently randomized nivolumab plus ipilimumab and chemotherapy arms of the international phase III CheckMate 816 trial.
Methods: Adults with stage IB-IIIA (American Joint Committee on Cancer seventh edition) resectable NSCLC received three cycles of nivolumab once every 2 weeks plus one cycle of ipilimumab or three cycles of chemotherapy (on day 1 or days 1 and 8 of each 3-week cycle) followed by surgery. Analyses included event-free survival (EFS), OS, pathologic response, surgical outcomes, biomarker analyses, and safety.
Results: A total of 221 patients were concurrently randomly assigned to nivolumab plus ipilimumab (n = 113) or chemotherapy (n = 108). At a median follow-up of 49.2 months, the median EFS was 54.8 months (95% CI, 24.4 to not reached [NR]) with nivolumab plus ipilimumab versus 20.9 months (95% CI, 14.2 to NR) with chemotherapy (HR, 0.77 [95% CI, 0.51 to 1.15]); 3-year EFS rates were 56% versus 44%. Higher rates of EFS events were initially seen, with later benefit favoring nivolumab plus ipilimumab; 3-year OS rates were 73% versus 61% (HR, 0.73 [95% CI, 0.47 to 1.14]); pathologic complete response rates were 20.4% versus 4.6%, respectively. In the respective arms, 83 (74%) and 82 patients (76%) underwent definitive surgery. Grade 3-4 treatment-related adverse events occurred in 14% and 36% of patients, respectively.
Conclusion: Neoadjuvant nivolumab plus ipilimumab showed potential long-term clinical benefit versus chemotherapy, despite early crossing of EFS curves in the preoperative phase and a lower rate of high-grade toxicity.