Merck & Co. Inc. (MRK) is seeking to expand the approval of its blockbuster cancer drug Keytruda in combination with chemotherapy for yet another indication – this time, for the treatment of patients with locally recurrent unresectable or metastatic triple-negative breast cancer whose tumors express PD-L1.This is the first time that Keytruda is facing the FDA for the breast cancer indication, with a decision expected on November 28, 2020. Keytruda is already approved for the indications of melanoma, non-small cell lung cancer, small cell lung cancer, head and neck squamous cell carcinoma, classical Hodgkin lymphoma, primary mediastinal large B-cell lymphoma, urothelial carcinoma, microsatellite instability-high cancer, gastric cancer, esophageal cancer, cervical cancer, hepatocellular carcinoma, Merkel cell carcinoma, renal cell carcinoma, endometrial carcinoma, tumor mutational burden-high (TMB-H) cancer, and cutaneous squamous cell carcinoma.The drug raked in sales of $11.08 billion in the full year of 2019 and $6.67 billion in the first half of 2020. MRK closed Friday’s (Oct.23, 2020) trading at $79.83, up 0.78.