Merck, today announced that the U.S. Food and Drug Administration (FDA) has approved KEYTRUDA® (pembrolizumab), the company’s anti-PD-1 (programmed death receptor-1) therapy, for the treatment of patients with recurrent locally advanced or metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma whose tumors express PD-L1 [Combined Positive Score (CPS) ≥1] as determined by an FDA-approved test, with disease progression on or after two or more prior lines of therapy including fluoropyrimidine- and platinum-containing chemotherapy and if appropriate, HER2/neu-targeted therapy. This indication is approved under the FDA’s accelerated approval regulations 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.

“Historically, advanced gastric cancer has been particularly challenging to treat, and new treatment options are needed for these patients,” said Charles S. Fuchs, M.D., MPH, lead investigator and director of Yale Cancer Center. “The results observed in the diverse population of heavily pretreated advanced gastric or GEJ patients from the KEYNOTE-059 clinical trial demonstrate that pembrolizumab in the third-line setting has the potential to shift how we care for certain patients facing this difficult-to-treat disease.”

Immune-mediated adverse reactions occurred with KEYTRUDA including pneumonitis, colitis, hepatitis, endocrinopathies, nephritis, and skin adverse reactions. Based on the severity of the adverse reaction, KEYTRUDA (pembrolizumab) should be withheld or discontinued and corticosteroids administered if appropriate. KEYTRUDA can also cause severe or life-threatening infusion-related reactions. Monitor patients for signs and symptoms of infusion-related reactions; for Grade 3 or 4 reactions, stop infusion and permanently discontinue KEYTRUDA. Based on its mechanism of action, KEYTRUDA can cause fetal harm when administered to a pregnant woman. Female patients of reproductive potential should be advised of the potential hazard to a fetus. For more information regarding immune-mediated and infusion-related adverse reactions and use in pregnancy, see “Selected Important Safety Information” below.

“KEYTRUDA is now the first PD-1 checkpoint inhibitor approved in the United States for previously treated advanced gastric or GEJ cancer, helping to address a recognized treatment gap,” said Dr. Roger M. Perlmutter, president, Merck Research Laboratories. “This approval marks another milestone – the tenth new indication for KEYTRUDA in just three years – which further demonstrates both our commitment to patients and the progress we have made in the fight against many cancers.”