Background: Many pts with advanced HCC progress on SOC therapy. Nivo is a fully human anti–PD-1 IgG4 mAb that demonstrated durable responses (20% ORR with a median DOR of 9.9 mo; 9-mo OS rate was 74%) in pts with advanced HCC in the dose-expansion (EXP) phase of the CheckMate 040 study (NCT01658878; Melero et al. 2017). Here we present survival and durability of response data in both sor-naive and -experienced pts with advanced HCC in CheckMate 040. Methods: Pts naive to or previously treated with sor received nivo in phase 1/2 dose-escalation (ESC; 0.1–10 mg/kg) and -EXP (3 mg/kg) cohorts Q2W regardless of PD-L1 status. Primary endpoints were safety/tolerability (ESC) and ORR (EXP; ORR by investigator [INV] and blinded independent central review [BICR]) using RECIST v1.1. Secondary endpoints included DOR, DCR, and OS. Biomarkers were assessed using pre-treatment tumor samples. Results: Overall, pts (N=262) had a median follow-up of 12.9 mo, and 98% had Child-Pugh scores 5–6. In sor-naive pts (n=80), the ORR (INV) was 23%, with 44% of responses (8/18) ongoing (Table). The DCR was 63%; 40% of pts had stable disease ≥6 mo. In sor-experienced pts (n=182; 91% progressed on sor), the ORRs (INV) were 16%–19%. Overall, responses occurred regardless of etiology or tumor cell PD-L1 expression. Nivo had a manageable safety profile consistent with that reported in other tumor types. Updated data with additional 4 mo of follow-up will be presented. Conclusions: Nivo demonstrated durable responses with long-term survival and favorable safety in both sor-naive and -experienced pts with advanced HCC. Clinical trial information: NCT01658878

NR, not reached; NE, not estimable. ^aRECIST v1.1; mRECIST ORRs (BICR): sor naive, 24%; sor experienced, 22% (ESC), 19% (EXP).