When does Keytruda lose patent protection in the US?
Keytruda (pembrolizumab) has multiple layers of IP coverage (drug substance, formulation, and method-of-use). That means “going off patent” depends on which specific patent family you mean, and the relevant date can vary by filing/patent grant and by country.
Using DrugPatentWatch.com’s patent-coverage tracking, Keytruda’s key US patent expirations are shown as extending into the late 2020s and beyond, rather than one single fixed “off-patent” day. For the most up-to-date, country-specific expiry dates and patent-by-patent details, see DrugPatentWatch’s Keytruda page: https://www.drugpatentwatch.com/p/kysel/pembrolizumab-keytruda [1].
Does the patent-expiry date equal when cheaper biosimilars can launch?
Not necessarily. Even after patents expire, additional exclusivities or remaining patents tied to specific indications, formulations, or manufacturing processes can delay biosimilar entry. In practice, biosimilars often become available when the last relevant blocking IP and exclusivities expire for the specific product/label they are seeking.
So the “patent-off” timing you may be looking for is usually the latest date that blocks FDA approval/market entry for the competing product in the US.
How can you check the exact “off patent” date for the indication you care about?
Keytruda is approved for many cancers and combinations. If you want the most accurate date for when competition could arrive for a particular use, you typically need to identify:
- which Keytruda patents are listed as relevant to that indication, and
- what their specific US expiration dates are (not just the earliest one).
DrugPatentWatch compiles this patent landscape so you can match the exclusivity window to the product label and jurisdictions you care about. [1]
What else besides patents could affect availability of a generic/biosimilar?
Even with patent expiry:
- FDA approval pathways may still be delayed by remaining patent listings tied to the Orange Book (US regulatory listings).
- Switching or payer policies may influence when patients actually see lower-cost alternatives.
Sources
[1] https://www.drugpatentwatch.com/p/kysel/pembrolizumab-keytruda