BAVENCIO, generically known as avelumab, is a prescription medication used in the field of oncology as an immunotherapy treatment. It is a type of drug known as a programmed death ligand-1 (PD-L1) blocking antibody, designed to help the body's immune system detect and fight cancer cells. BAVENCIO works by inhibiting the interaction between PD-L1 and its receptors, PD-1 and B7.1, which can otherwise lead to the suppression of the immune response against cancer cells. This medication is used to treat various types of cancer, including Merkel cell carcinoma (a rare form of skin cancer), urothelial carcinoma (bladder cancer), and renal cell carcinoma (kidney cancer), among others. It is administered through intravenous infusion and its use is associated with a range of potential side effects, which necessitates close monitoring by healthcare professionals.