Shah MA, et al. - Among 121 heavily pretreated patients with advanced, metastatic esophageal cancer enrolled in the phase 2 KEYNOTE-180 study (phase 2, open-label, interventional, single-arm study), researchers investigated the efficacy and safety of pembrolizumab. Patients were enrolled from January 12, 2016, to March 21, 2017, from 57 sites in 10 countries. These patients received 200 mg pembrolizumab intravenously every 3 weeks until disease progression, unacceptable toxic effects, or study withdrawal, for up to 2 years. Follow-up of 5.8 months was performed in enrolled patients including 100 men and 21 women; median age, 65 years [range, 33-87 years], 18 (14.9%) had undergone 3 or more prior therapies, 63 (52.1%) had esophageal squamous cell carcinoma (ESCC), and 58 (47.9%) had tumors positive for programmed death ligand-1 (PD-L1). With pembrolizumab, an objective response rate of 9.9% was seen, 12 patients had partial responses per the Response Evaluation Criteria in Solid Tumors, version 1.1, by central imaging review. Compared to safety profile previously seen with pembrolizumab, a manageable and similar safety profile was reported in this study.