Keytruda (pembrolizumab) is a medication used for the treatment of advanced melanoma, metastatic nonsquamous NSCLC, recurrent or metastatic Head and Neck Squamous Cell Carcinoma (HNSCC), recurrent classical Hodgkin Lymphoma (cHL), locally advanced or metastatic urothelial carcinoma, solid tumours having the biomarkers MSI-H or dMMR, recurrent locally advanced or metastatic gastric or gastroesophageal junction adenocarcinoma.