Kohei Shitara, MD, National Cancer Center Hospital East, Chiba, Japan, discusses findings from an exploratory analysis of tumor gene expression and clinical outcomes in subjects with previously treated gastric cancer (GC) from the KEYNOTE-061 study (NCT02370498). Pembrolizumab therapy did not significantly prolong overall survival (OS) vs paclitaxel in patients with PD-L1-positive GC but was associated with a longer duration of response (DOR). The TcellinfGEP-adjusted mMDSC signature was negatively associated with clinical outcomes for pembrolizumab, while the TcellinfGEP-adjusted glycolysis, MYC, and proliferation signatures were negatively associated with OS for paclitaxel. This exploratory biomarker analysis suggests that myeloid-driven suppression may play a role in resistance to PD-1 immune checkpoint blockade and supports a strategy of considering immunotherapy combinations. This interview was recorded at the American Association for Cancer Research (AACR) Annual Meeting 2022 in New Orleans, LA.
