Additional Relevant Details The Phase 1b/2 multicenter, open-label clinical trial will be conducted in two parts. The Phase 1b portion is designed to determine the safety and tolerability of margetuximab in combination with pembrolizumab in patients with advanced gastric cancer, while the Phase 2 portion will evaluate the anti-tumor activity of margetuximab in combination with pembrolizumab in patients with advanced HER2-positive gastric cancer.  

Treatment options for patients with advanced HER2-positive gastric cancer are extremely limited. The combination of complementary mechanisms engaged by margetuximab and pembrolizumab could provide an important alternative for patients who do not respond to currently available regimens.