Merck & Co. Inc.'s (MRK) subcutaneous formulation of its blockbuster cancer drug Keytruda is under review in the U.S., with a decision anticipated on September 23, 2025.Keytruda in intravenous formulation is approved for the treatment of various types of cancers, say, Biliary Tract Tumor, Breast Cancer, Cervical Cancer, Endometrial Cancer, Esophageal Carcinoma, Gastric Cancer, Head and Neck Cancer, Hepatocellular Carcinoma, Hodgkin's Lymphoma, Malignant Pleural Mesothelioma, Melanoma, Merkel Cell Carcinoma, Non-Small Cell Lung Cancer, Renal Cell Carcinoma, Squamous Cell Carcinoma, and Urothelial Carcinoma.In clinical studies, subcutaneous Keytruda reduced time demands for both patients and healthcare providers, while maintaining the same efficacy and safety profile as IV Keytruda. According to the company, compared to the IV formulation, subcutaneous Keytruda reduced the time patients spent in the chair and treatment room by 49.7% and 47.4%, respectively. It also decreased the total active time healthcare professionals spent on treatment preparation, administration, and patient monitoring by 45.7%.Keytruda generated sales of $8 billion in the second quarter of 2025 compared to $7.3 billion in the year-ago quarter. MRK closed Wednesday’s (Aug.27, 2025) trading at $84.07, down 1.08%.