Until Dec. 31st 2021, the median follow-up was 5.6 months. ORR was 57.6% in sintilimab arms vs. 42.9% in pembrolizumab arms, and the confirmed ORR was 45.5% (15/33) vs. 28.6% (10/35), separately.The disease control rate was 87.9% vs. 91.4% in sintilimab and pembrolizumab arms, respectively. The primary endpoint was reached, with 15 confirmed PRs achieved in sintilimab arms. Survival data was still immature. Treatment-related adverse events were comparable between sintilimab and pembrolizumab arms. This head-to-head study of PD-1 inhibitors suggested comparable tumor response and similar safety profile between sintilimab and pembrolizumab.