CHICAGO – Following last year’s Checkmate-238 data showing that PD-1 inhibitor Opdivo (nivolumab, Bristol Myers Squibb Co.) was better at improving relapse-free survival (RFS) than CTLA-4 inhibitor Yervoy (ipilimumab, BMS) in melanoma patients after surgery, Kenilworth, N.J.-based Merck & Co. Inc. presented data for its own PD-1 inhibitor, Keytruda (pembrolizumab), in the melanoma adjuvant setting at the American Association for Cancer Research Annual Meeting 2018. (See BioWorld, Sept. 12, 2017.)