Subset analysis of overall survival (OS) by prior therapy. Nonrandomized subset analysis of OS in treatment-naive (n = 604) and previously treated (n = 1,257) patients with metastatic melanoma who received ipilimumab in 10 prospective trials and two retrospective, observational studies. Median OS was 13.5 months (95% CI, 11.9 to 15.4 months) for treatment-naive patients and 10.7 months (95% CI, 9.6 to 11.4 months) for previously treated patients, with 3-year survival rates of 26% (95% CI, 21% to 30%) and 20% (95% CI, 18% to 23%), respectively. Crosses indicate censored patients.