CTLA4 and melanoma: Background: The phase 3 study CheckMate 067 (NCT01844505) showed improved progression-free survival (PFS) and objective response rate (ORR) by RECIST v1.1 for NIVO (anti-PD-1) + IPI (anti-CTLA-4) (median 11.5 months [mo], 58 %) or NIVO (6.9 months, 44 %) compared with IPI (2.9 months, 19 %) in patients (pts) with previously untreated advanced melanoma [1]; however, long-term follow-up data including overall survival (OS) are not yet available.