Kohei Shitara, MD, National Cancer Center Hospital East, Chiba, Japan, discusses the exploratory efficacy analyses of biomarkers from the randomized Phase III CheckMate-649 trial (NCT02872116). The CheckMate-649 trial demonstrated that patients with gastric cancer, gastrooesophageal junction cancer, and oesophageal adenocarcinoma had a greater overall survival (OS) when treated with first-line nivolumab plus chemotherapy compared to patients treated with chemotherapy alone. To identify which patients would benefit the most from nivolumab plus chemotherapy, an efficacy analysis was performed by tumor mutational burden (TMB) and gene expression signatures (GES). TMB was derived by whole-exome sequencing of baseline tumors and matching blood, where TMB-high was defined as 199 or more mutations per exome. RNA sequencing of baseline tumor tissue was performed to assess GES. OS benefits were observed with nivolumab plus chemotherapy compared to chemotherapy alone regardless of TMB and GES status. Importantly, nivolumab plus chemotherapy had the most significant improvement in OS compared to chemotherapy in TMB-high patients. This interview was recorded at the American Association for Cancer Research (AACR) Annual Meeting 2022 in New Orleans, LA.
