Nivolumab Plus Ipilimumab vs Nivolumab for Previously Treated Patients With Stage IV Squamous Cell Lung Cancer: The Lung-MAP S1400I Phase 3 Randomized Clinical Trial.

Importance Nivolumab plus ipilimumab is superior to platinum-based chemotherapy in treatment-naive advanced non–small cell lung cancer (NSCLC). Nivolumab is superior to docetaxel in advanced pretreated NSCLC. Objective To determine whether the addition of ipilimumab to nivolumab improves survival in patients with advanced, pretreated, immunotherapy-naive squamous (Sq) NSCLC. Design, Setting, and Participants The Lung Cancer Master Protocol (Lung-MAP) S1400I phase 3, open-label randomized clinical trial was conducted from December 18, 2015, to April 23, 2018, randomizing patients in a 1:1 ratio to nivolumab alone or combined with ipilimumab. The median follow-up in surviving patients was 29.5 months. The trial was conducted through the National Clinical Trials Network and included patients with advanced immunotherapy-naive SqNSCLC and a Zubrod score of 0 (asymptomatic) to 1 (symptomatic but completely ambulatory) with disease progression after standard platinum-based chemotherapy. Randomization was stratified by sex and number of prior therapies (1 vs 2 or more). Data were analyzed from May 3, 2018, to February 1, 2021. Interventions Nivolumab, 3 mg/kg intravenously every 2 weeks, with or without ipilimumab, 1 mg/kg intravenously every 6 weeks, until disease progression or intolerable toxic effects. Main Outcomes and Measures The primary end point was overall survival (OS). Secondary end points included investigator-assessed progression-free survival (IA-PFS) and response per Response Evaluation Criteria in Solid Tumors (RECIST) guidelines, version 1.1. Results Of 275 enrolled patients, 252 (mean age, 67.5 years [range 41.8-90.3 years]; 169 men [67%]; 206 White patients [82%]) were deemed eligible (125 randomized to nivolumab/ipilimumab and 127 to nivolumab). The study was closed for futility at a planned interim analysis. Overall survival was not significantly different between the groups (hazard ratio [HR], 0.87; 95% CI, 0.66-1.16;P = .34). Median survival was 10 months (95% CI, 8.0-14.4 months) in the nivolumab/ipilimumab group and 11 months (95% CI, 8.6-13.7 months) in the nivolumab group. The IA-PFS HR was 0.80 (95% CI, 0.61-1.03;P = .09); median IA-PFS was 3.8 months (95% CI, 2.7-4.4 months) in the nivolumab/ipilimumab group and 2.9 months (95% CI, 1.8-4.0 months) in the nivolumab alone group. Response rates were 18% (95% CI, 12%-25%) with nivolumab/ipilimumab and 17% (95% CI, 10%-23%) with nivolumab. Median response duration was 28.4 months (95% CI, 4.9 months to not reached) with nivolumab/ipilimumab and 9.7 months with nivolumab (95% CI, 4.2-23.1 months). Grade 3 or higher treatment-related adverse events occurred in 49 of 124 patients (39.5%) who received nivolumab/ipilimumab and in 41 of 123 (33.3%) who received nivolumab alone. Toxic effects led to discontinuation in 31 of 124 patients (25%) on nivolumab/ipilimumab and in 19 of 123 (15%) on nivolumab. Conclusions and Relevance In this phase 3 randomized clinical trial, ipilimumab added to nivolumab did not improve outcomes in patients with advanced, pretreated, immune checkpoint inhibitor–naive SqNSCLC. Trial Registration ClinicalTrials.gov Identifier:NCT02785952