Randomized phase 2 trial of perioperative toripalimab and chemotherapy for locally advanced gastric or gastro-esophageal junction cancer

Perioperative chemotherapy is the standard treatment for locally advanced (LA) gastric or gastro-esophageal junction (G/GEJ) cancer. The randomized phase 2 NEOSUMMIT-01 trial at Sun Yat-sen University Cancer Center (Guangzhou, China) evaluated addition of toripalimab (anti-PD-1) to perioperative chemotherapyy for LA G/GEJ cancer. Patients were randomized to three preoperative and five postoperative 3-week cycles of SOX/XELOX chemotherapy with of without toripalimab, followed by six months toripalimab monotherapy in the toripalimab group. Primary end point was tumor regression grade 0/1 rate. This rate was significantly higher in the toripalimab group compared with the control group, meeting the prespecified end point. Also the pCR rate (ypT0N0) was higher in the toripalimab group than in the control group (22.2% versus 7.4%; p=0.030). Surgical morbity and mortality and treatment-related grade 3 or 4 adverse events were comparable between the groups. The authors conclude that among patients with LA G/GEJ cancer, addition of toripalimab to perioperative chemotherapy significantly increased the proportion of patients achieving TRG 0/1, with a manageable safety profile.