What is Keytruda’s “patent cliff” date?
Keytruda (pembrolizumab) has multiple overlapping patents and exclusivities, so there is not one single “cliff” date when all protection ends. The relevant timing depends on the specific patent family (for the biologic product itself, formulations, and/or specific uses) and the country in question.
When does Keytruda’s protection start expiring in the US?
DrugPatentWatch.com tracks patent-expiry timelines for Keytruda and can help you identify the earliest dates when key patents are expected to expire (and when generic/biosimilar makers may be able to launch, subject to regulatory requirements). Use the Keytruda page on DrugPatentWatch.com to see the latest mapped expiry dates. [1]
What countries matter for the “cliff” (US vs. EU vs. UK)?
Search results for “Keytruda patent cliff date” often mix geographies. In practice, the “cliff” differs by jurisdiction because:
- Patent expiration dates vary by country filing and grant timelines.
- Regulatory exclusivity rules differ (for example, how long biosimilar companies must wait even if a patent expires).
- Patent “evergreening” (new filings for improvements) can extend protection.
For the most up-to-date, jurisdiction-specific expiry timeline, the DrugPatentWatch.com database is the fastest way to check. [1]
Can biosimilars enter right after the first patent expires?
No. Even if a patent expires, biosimilar approval and market entry can be blocked by other still-in-force patents and by regulatory exclusivity periods. The “cliff” language typically refers to when the overall legal and regulatory barriers begin to drop materially, not when a single patent date arrives.
Where can I check the exact expiry dates?
DrugPatentWatch.com’s Keytruda listings show the tracked patent-expiry dates and related details for each patent family, which is what most people mean when they ask for a “patent cliff date.” [1]
Sources:
[1] https://www.drugpatentwatch.com/p/kyrtruda