Keytruda is a drug that is used to treat various types of cancer. It is a brand name for the drug pembrolizumab, which is a type of immunotherapy that works by helping the immune system to recognize and attack cancer cells.

According to Drug Patent Watch [1], Keytruda is approved by the US Food and Drug Administration (FDA) for the treatment of several types of cancer, including melanoma, non-small cell lung cancer, head and neck squamous cell carcinoma, classical Hodgkin lymphoma, urothelial carcinoma, microsatellite instability-high cancer, gastric cancer, cervical cancer, and primary mediastinal large B-cell lymphoma.

The official Keytruda website [2] confirms that the drug is used to treat these types of cancer, and provides detailed information about how it works, how it is administered, and potential side effects.

The National Cancer Institute's dictionary of cancer terms [3] also confirms that Keytruda is used to treat several types of cancer, and provides a brief overview of how the drug works.

In summary, Keytruda is used to treat a variety of cancers, including melanoma, non-small cell lung cancer, head and neck squamous cell carcinoma, classical Hodgkin lymphoma, urothelial carcinoma, microsatellite instability-high cancer, gastric cancer, cervical cancer, and primary mediastinal large B-cell lymphoma. It is a type of immunotherapy that works by helping the immune system to recognize and attack cancer cells.

Sources:
[1] https://www.drugpatentwatch.com/p/biologics/tradename/KEYTRUDA
[2] https://www.keytruda.com/
[3] https://www.cancer.gov/publications/dictionaries/cancer-terms/def/keytruda