1281PAssessment of real-world effectiveness of first-line (1L) nivolumab (NIVO) plus ipilimumab (IPI) or NIVO monotherapy for advanced melanoma: A retrospective cohort study. (23rd October 2018) - Freeman, M; Gupte-Singh, K; You, M; Le, T K; Ritchings, C; Rao, S; Jang, S