Impact of prior nivolumab on treatment outcomes of taxane plus ramucirumab in advanced gastric cancer

Background Several studies have indicated that exposure to immune checkpoint inhibitors (ICIs) can enhance the efficacy of subsequent chemotherapy. Although combination chemotherapy with ICI has become a standard first-line treatment for human epidermal growth factor receptor 2 (HER2)-negative advanced gastric cancer (AGC), its impact on the efficacy of taxane plus ramucirumab (RAM) remains uncertain. Methods We retrospectively analyzed data from consecutive patients with HER2-negative AGC who had previously received oxaliplatin-based chemotherapy, with or without nivolumab, followed by taxane plus RAM between March 2015 and July 2024. Patients were categorized into two cohorts according to prior nivolumab exposure: cohort A (ICI-naïve) and cohort B (ICI-exposed). Survival outcomes and toxicity were compared between the cohorts. Results A total of 191 patients were evaluated (158 in cohort A and 33 in cohort B). The median follow-up period (range) was 7.5 (0.2–79.4) months. The median overall survival was 7.8 months in cohort A and 7.6 months in cohort B [hazard ratio (HR), 1.24; 95% confidence interval (CI), 0.83–1.86; P = .293]. The median progression-free survival was 3.5 and 3.9 months, respectively (HR, 1.05; 95% CI, 0.72–1.55; P = .787). The overall response rate was 30.7% in cohort A and 15.4% in cohort B (P = .338). No new safety concerns were identified. Conclusion Prior ICI exposure may not significantly affect the efficacy or safety of subsequent taxane plus RAM therapy.