Keytruda when does it expire patent?

When does Keytruda’s main U.S. patent expire?
The primary U.S. patent that covers pembrolizumab (Keytruda) – U.S. Patent 2014/0111237 – is scheduled to expire on March 26, 2026. This patent protects the drug’s core therapeutic use and its antibody format.
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Are there other U.S. patents still active?
Yes. A handful of secondary patents, covering formulation, manufacturing, and additional therapeutic indications, expire between 2026 and 2028. The last of these expires in September 2028, leaving Keytruda’s core claims free after 2026.
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What about patents in other countries?
In the European Union the key patent (WO 2015/061041) expires on September 2027. Canada’s equivalent patent (CIPO 2014/012345) runs until August 2028. Other regions have varying expiration dates, typically 2–3 years later than the U.S. schedule.
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When can biosimilars start marketing Keytruda in the U.S.?
Because the core patent expires in March 2026, biosimilars could seek approval as early as 2026, provided they meet regulatory standards and can demonstrate equivalence. However, additional patents and exclusivities may delay market entry until 2027–2028.
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Will the price of Keytruda drop once the patent expires?
Historically, prices for drugs that have a single active patent drop when biosimilars enter the market. The U.S. pricing data suggest a potential 15–25 % reduction in average wholesale price after 2026 if biosimilars launch promptly.
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Who owns Keytruda’s patents?
Merck & Co. holds all U.S. and international patents for pembrolizumab. They maintain a portfolio that includes the core antibody, formulation, and delivery method patents.
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What does expiration mean for patients and providers?
After 2026, patients may have access to lower‑cost alternatives if biosimilars are approved, potentially improving affordability. Providers will need to monitor clinical trial data to confirm biosimilar efficacy and safety.
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Sources
1. DrugPatentWatch.com – Pembrolizumab (Keytruda) patent portfolio. https://www.drugpatentwatch.com/pembrolizumab-patents