
Every year, more than 1 million individuals are diagnosed with gastric and gastroesophageal junction cancers. However, there are only a small number of effective treatments.
A new double-blind, phase 3 study led by Jianming Xu, MD, and published in JAMA found that a combination treatment of sintilimab and first-line chemotherapy improved survival for patients with previously untreated advanced gastric and gastroesophageal junction cancers.
The randomized trial analyzed the data of 650 patients with unresectable locally advanced or metastatic gastric or gastroesophageal junction cancers from January 2019 to August 2020.
The trial’s primary end point was overall survival (OS) time from randomization.
Following a 1:1 ratio, the patients received either sintilimab (n=327) or placebo (n=323) in combination with capecitabine and oxaliplatin every 3 weeks for a minimum of 6 weeks. Patients underwent maintenance therapy with sintilimab or placebo plus capecitabine for a maximum of 2 years.
For all patients, sintilimab improved survival rates when compared with placebo (median, 15.2 vs 12.3 months; stratified hazard ratio [HR], 0.77; 95% CI, 0.63-0.94; P=.009).
Of the 650 patients, 397 (61.1%) had tumors with a PD-L1 combined positive score (CPS) of 5 or more, 563 (86.6%) discontinued study treatment, and 388 (59.7%) died. For patients who presented with a CPS of 5 or higher, sintilimab increased OS when compared with placebo (median, 18.4 vs 12.9 months; HR, 0.66; 95% CI, 0.50-0.86; P=.002).
Researchers reported that the most common grade 3 or higher treatment-related adverse events included a decreased platelet count (sintilimab, 24.7% vs placebo, 21.3%), a decreased neutrophil count (sintilimab, 20.1% vs placebo, 18.8%), and anemia (sintilimab, 12.5% vs placebo, 8.8%).
The investigators concluded that sintilimab shows promise as a beneficial treatment option.
“Among patients with unresectable locally advanced or metastatic gastric and gastroesophageal junction adenocarcinoma treated with first-line chemotherapy, sintilimab significantly improved overall survival for all patients and for patients with a CPS of 5 or more compared with placebo,” researchers wrote.