Nivolumab versus ipilimumab in the treatment of advanced melanoma: a critical appraisal: ORIGINAL ARTICLE: Wolchok JD, Chiarion-Sileni V, Gonzalez R et al. Overall survival with combined nivolumab and ipilimumab in advanced melanoma. N Engl J Med 2017; 377:1345-56

Aim: To show whether either nivolumab in combination with ipilimumab or nivolumab monotherapy vs. ipilimumab monotherapy extends overall survival (OS) or progression-free survival (PFS) in adults with previously untreated, advanced melanoma.

Setting And Design: The trial was conducted at 137 sites in 21 countries. Randomization (n = 945; 1 : 1 : 1 ratio) was stratified according to metastasis stage, BRAF mutation status and programmed death ligand 1 status.

Study Exposure: Adults were randomized to one of the following: nivolumab plus ipilimumab every 3 weeks for four doses, followed by nivolumab every 2 weeks; nivolumab every 2 weeks plus placebo; or ipilimumab every 3 weeks for four doses plus placebo. Treatment was continued until progression, unacceptable toxicity or withdrawal.

Outcomes: OS, PFS and objective response rate were determined. Patients were also assessed for adverse events. The primary end points of interest were OS and PFS, comparing either the nivolumab plus ipilimumab group or the nivolumab-only group with the patients treated with ipilimumab only.

Results: At 3 years, the OS rates were 58%, 52% and 34% for the nivolumab plus ipilimumab, the nivolumab monotherapy and the ipilimumab monotherapy groups, respectively. For the nivolumab plus ipilimumab group, the median OS was not reached at the time of analysis. For the nivolumab-only group, the median OS was 37·6 months, and the ipilimumab-only group had a median OS of 19·9 months. The hazard ratio for death was 0·55 [95% confidence interval (CI) 0·45-0·69; P < 0·001] comparing nivolumab plus ipilimumab with ipilimumab, and 0·65 (95% CI 0·53-0·80; P < 0·001) comparing nivolumab with ipilimumab. The PFS rates at 3 years were 39% for the nivolumab plus ipilimumab group, 32% for the nivolumab monotherapy group and 10% for the ipilimumab monotherapy group, with 95% CIs for the two nivolumab groups that did not overlap with that for ipilimumab alone.

Conclusions: Among patients with advanced melanoma, significantly longer OS and PFS occurred with the combination of nivolumab plus ipilimumab or with nivolumab alone compared with ipilimumab alone. Furthermore, survival outcomes favoured the nivolumab-containing groups over the ipilimumab group in subgroup analyses.