FDA accelerated approval to Keytruda for HER2-positive gastric cancer

The US Food and Drug Administration has approved Keytruda (pembrolizumab), Merck & Co’s (NYSE: MRK) blockbuster anti-PD-1 therapy, in combination with trastuzumab, fluoropyrimidine- and platinum-containing chemotherapy, for the first-line treatment of patients with locally advanced unresectable or metastatic HER2-positive gastric or gastroesophageal junction (GEJ) adenocarcinoma.

This indication is approved under accelerated approval based on tumor response rate and durability of response; continued approval for this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials.

This approval is based on data from the ongoing Phase III KEYNOTE-811 trial, in which Keytruda, which generated $14.4 billion revenues in its string of current indications in 2021, in combination with trastuzumab and either 5-fluorouracil plus cisplatin or capecitabine plus oxaliplatin demonstrated a statistically significant objective response rate (ORR) of 74% (95% CI, 66-82) for patients who received the regimen with Keytruda versus 52% (95% CI, 43-61) for those who received trastuzumab and chemotherapy alone (p<0.0001).