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# Merck’s Keytruda Gains OK in Gastric Cancer
- URL: https://www.fdaweb.com/mercks-keytruda-gains-ok-in-gastric-cancer/
- Published: 2023-11-17T12:00:00.000Z
- Updated: 2026-09-14T14:16:31.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5155820

FDA has approved a Merck NDA for Keytruda (pembrolizumab) and its use with fluoropyrimidine- and platinum-containing chemotherapy for treating (first line) adults with locally advanced unresectable or metastatic HER2-negative gastric or gastroesophageal junction (GEJ) adenocarcinoma.

Approval was based on data from KEYNOTE-859 (NCT03675737), a multicenter, randomized, double-blind, placebo-controlled trial that enrolled 1,579 patients with HER2-negative advanced gastric or GEJ adenocarcinoma who had not previously received systemic therapy, according to an [agency release](https://www.cancer.gov/news-events/cancer-currents-blog/2023/fda-pembrolizumab-stomach-esophageal-her2-pdl1?cid=eb%5Fgovdel&ref=fdaweb.com). The primary endpoint was overall survival (OS), and secondary efficacy outcome measures included progression free survival (PFS), overall response rate (ORR), and duration of response (DOR). “Treatment with pembrolizumab and chemotherapy resulted in a statistically significant improvement in OS, PFS, and ORR,” FDA says.

The agency notes that permanent discontinuation of pembrolizumab due to adverse reactions occurred in 15% of patients. Adverse reactions resulting in permanent discontinuation were infections and diarrhea.