CD274 and gastroesophageal junction adenocarcinoma: However, after accelerating FDA approval, pembrolizumab failed to demonstrate significant survival improvements in the following phase 3 trials (KEYNOTE-061 [NCT#02370498; efficacy as a second-line therapy] and KEYNOTE-062 [NCT#02494583; efficacy as a first-line therapy]) in patients with advanced G/GEJ adenocarcinoma showing a PD-L1 CPS of ≥1 [5,6,11,18].