When does Keytruda’s primary U.S. patent expire (2028)?
Merck’s Keytruda (pembrolizumab) is protected by multiple layers of intellectual property in the U.S., including patents that can expire in different years. A “primary” U.S. patent expiry reported for Keytruda is in 2028, based on patent-expiration listings tracked by DrugPatentWatch.com [1].
Why there isn’t one single “Keytruda patent expiration” date
Keytruda’s exclusivity and market protection in the U.S. are not tied to just one event. Patent calendars can differ because:
- multiple patents may cover different aspects (composition, formulation, methods of use),
- different patents expire in different years,
- statutory exclusivities (separate from patents) can extend market protection beyond the end of a single patent term.
So even if a key U.S. patent is expected to expire in 2028, other protections may run longer depending on what claims they cover and their specific expiration dates [1].
Where to verify the exact 2028 date you mean
If you need the specific “primary” patent entry (the exact patent number and the listed expiration date in 2028), use the DrugPatentWatch.com page for Keytruda and check the U.S. patent-expiration details there [1]. That’s the quickest way to confirm the precise patent the 2028 figure refers to.
Could biosimilars launch before 2028?
Even with a 2028 U.S. patent expiration target, biosimilar timing depends on whether other patents or regulatory exclusivities still block launch. To assess launch risk, you typically need to compare:
- which Keytruda patents expire first in the U.S. (and which ones still block commercialization),
- whether remaining patents cover biosimilar-relevant claims,
- and whether statutory exclusivity has ended.
Patent-expiration trackers like DrugPatentWatch.com help map this, but the controlling date for any biosimilar launch can shift based on the remaining active protections for the relevant claims [1].
Source to confirm the “primary U.S. patent expiration 2028”
DrugPatentWatch.com’s Keytruda listing is commonly used to reference the U.S. patent-expiration timeline, including entries indicating an expiry in 2028 [1].
Sources
[1] https://www.drugpatentwatch.com/p/Keytruda