An observational study of the effectiveness and safety of nivolumab plus chemotherapy for untreated advanced or recurrent gastric cancer in Japanese real-world settings: the G-KNIGHT study.

Background: Nivolumab plus chemotherapy has shown efficacy in clinical trials for advanced or recurrent gastric cancer (GC). However, real-world utilization data are limited. In this study, we aimed to assess the effectiveness, safety, and treatment status of first line nivolumab plus chemotherapy in Japanese patients with treatment-naïve advanced or recurrent GC.

Methods: Untreated patients with advanced or recurrent GC who initiated nivolumab plus chemotherapy as first line treatment from November 2021 to June 2023 across 23 Japanese sites were enrolled in this observational study (G-KNIGHT). This report focused on the objective response rate (ORR), real-world progression-free survival (rwPFS), and the treatment-related adverse event (TRAE) incidence. Furthermore, subgroup analyses for ORR and rwPFS were conducted for patients stratified by various factors including age and the programmed cell death ligand 1 (PD-L1) combined positive score (CPS).

Results: Among 527 patients (median age, 70.3 years; 25.2% aged ≥ 75 years; 65.5% male; 84.3% with advanced GC), the median follow-up period was 10.4 (interquartile range, 6.7-15.2) months. The ORR was 65.6% (95% confidence interval [CI], 59.9-70.9%). The median rwPFS (months, 95% CI) was 6.9 (6.2-7.6); by subgroups: age < 75 years, 6.7 (6.0-7.5); age ≥ 75 years, 7.4 (6.2-8.6); PD-L1 CPS < 1, 7.5 (6.5-9.0); CPS 1-5, 6.2 (5.5-8.0); and CPS ≥ 5, 7.0 (6.2-8.2). TRAEs occurred in 91.3% of patients, with 40.4% experiencing grade ≥ 3 events.

Conclusions: This large-scale real-world study supports the effectiveness and safety of nivolumab plus chemotherapy in untreated Japanese patients with advanced or recurrent GC.