See the DrugPatentWatch profile for keytruda

The patent expiration date for Keytruda, a medication used to treat various types of cancer, is not explicitly stated in the information provided. However, it is mentioned that the drug's active ingredient is pembrolizumab [1].

According to DrugPatentWatch.com, the patent for pembrolizumab is set to expire in the United States on November 12, 2028 [2]. This does not necessarily mean that generic versions of Keytruda will become available immediately after this date, as there can be a transition period.

After the patent expiration, other companies can apply to produce generic versions of the drug. This process includes FDA review and approval, which can take some time. Therefore, while the patent expiration date provides a general idea, it does not indicate the exact date when generic versions will enter the market.

Sources:
[1] "Keytruda (pembrolizumab) for Injection, for intravenous use." National Library of Medicine, U.S. National Institutes of Health. Retrieved from https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4a9d2e2e-d97e-4e1e-8acc-68febf6a8527&type=display
[2] "Pembrolizumab (Keytruda) Patent Expiration & Generic Entry." DrugPatentWatch.com. Retrieved from https://www.drugpatentwatch.com/patent/pembrolizumab-keytruda/