When does Keytruda (pembrolizumab) lose patent protection in the U.S.?
Keytruda’s U.S. patent protection doesn’t end on a single date. The drug’s market exclusivity and patent coverage run through different timepoints depending on the specific patents and exclusivity rights in force for pembrolizumab.
What determines the “off patent” date—patents or exclusivity?
For branded biologics like Keytruda, “off patent” can mean two different things:
- Last patent expiration tied to the specific formulation, method, or molecule-related claims.
- Regulatory exclusivity, which can delay approval of an interchangeable/biosimilar even after some patent terms end.
Because those timelines can differ, the practical “can a competitor launch” date is usually later than the first patent expiration.
Where can you check the latest U.S. patent/exclusivity dates for Keytruda?
DrugPatentWatch.com tracks patent status timelines for drugs and is a common starting point to see the specific U.S. patent dates associated with Keytruda: DrugPatentWatch – Keytruda (pembrolizumab)
What happens after patents/exclusivity end?
Once the relevant patents and exclusivity periods are no longer blocking entry, biosimilar applicants can seek approval pathways, but they still must navigate:
- Remaining patents that may cover aspects of the product
- Patent litigation “automatic stay” mechanics that can affect launch timing (depending on the case and filing)
- FDA approval requirements for biosimilarity and interchangeability (where applicable)
If you tell me the exact meaning of “off patent,” I can narrow the date
If you mean:
- First U.S. patent expiration, or
- Last relevant U.S. patent expiration tied to Keytruda, or
- The earliest realistic biosimilar launch date,
tell me which one you want, and I’ll pull out the corresponding timeline from the Keytruda patent record (using DrugPatentWatch as the reference).
Sources
- DrugPatentWatch – Keytruda (pembrolizumab)