Readministration of nivolumab for patients with advanced gastric cancer: a case series

Background: Nivolumab (NIVO), an immune checkpoint inhibitor (ICI) combined with chemotherapy, represents the standard of care for patients with human epidermal growth factor receptor 2-negative advanced gastric cancer (AGC). Although ICI readministration either as a rechallenge following disease progression or as a reintroduction after refractory has demonstrated clinical benefit and safety in patients with lung cancer or melanoma, evidence in AGC remains limited. Patients and methods: This case series analyzed eight patients with AGC who received NIVO readministration monotherapy between September 2017 and December 2021. Results: Six patients transitioned after disease progression, while two patients discontinued initial NIVO due to grade 2 pneumonitis. Among six patients with NIVO rechallenge, median progression-free survival (PFS) after rechallenge was 1.8 months [95% confidence interval (CI) 0.6-19.3 months], and median overall survival (OS) was 17.9 months (95% CI 1.8-42 months). Two patients achieved stable disease. Patients with ascites, Eastern Cooperative Oncology Group performance status of 1, or bulky liver/peritoneal metastasis tended toward shorter PFS and OS. Among two patients with NIVO reintroduction, one patient experienced a grade 2 rash; however, neither patient developed pneumonitis. Conclusions: NIVO readministration may offer clinical benefit to selected patients with AGC, without inducing severe adverse events.