Keytruda's Patent Expiry Timeline
Keytruda (pembrolizumab), Merck's blockbuster PD-1 inhibitor for cancers like melanoma and lung cancer, faces generic (biosimilar) entry no earlier than 2028 due to ongoing patent protections. The main composition-of-matter patent (US 8,008,449) expires in 2028, but multiple secondary patents extend exclusivity into the 2030s for specific formulations and methods.[1][2]
When Do Core Patents Expire?
- Primary patent US 8,008,449 (anti-PD-1 antibody): Expires April 2028.
- Key formulation patents (e.g., US 9,220,779 for the injectable suspension): Extend to 2036.
- Method-of-use patents for various indications (e.g., US 9,492,539 for NSCLC): Valid until 2033–2037.[2]
Biosimilars cannot launch until all blocking patents are resolved, likely pushing first entry to 2030 or later absent settlements.
Are Biosimilars Already Approved?
The FDA has approved six Keytruda biosimilars, including those from Samsung Bioepis (approved 2024, launch delayed to 2028 by settlement), Organon/Viatris, and Biocon/Mylan.[3] These await patent settlements or litigation outcomes for market entry.
What Settlements Delay Launches?
Merck settled with multiple challengers:
- Samsung Bioepis: Launch January 2028.
- Organon/Viatris: Potential entry 2028–2030.
- Biocon/Mylan: Post-2030.
These agreements stagger biosimilar access, preserving Merck's revenue (Keytruda hit $25B in 2023 sales).[4]
Ongoing Patent Challenges
BioPharma firms like Amgen, Pfizer, and Seagen filed Paragraph IV challenges under the BPCIA, triggering litigation. A 2023 PTAB decision invalidated some claims, but appeals continue. Full resolution could take years, with risks of earlier entry if Merck loses key cases.[2][5]
How Does This Compare to Opdivo?
Bristol Myers Squibb's Opdivo (nivolumab) saw its first biosimilar approved in 2024 (Samsung's), but launches are delayed to 2028–2031 via similar settlements. Keytruda's later expiry gives it a multi-year edge.[3]
Impact on Patients and Pricing
Biosimilars could cut U.S. prices 20–30%, based on Humira precedents, improving access for the 500,000+ annual patients. Current Keytruda list price: ~$11,000/month. No generics until at least 2028 means sustained high costs.[4]
[1]: DrugPatentWatch.com - Keytruda Patents
[2]: FDA Orange Book - Pembrolizumab
[3]: FDA Biosimilar Approvals
[4]: Merck Q4 2023 Earnings
[5]: PTAB Decisions on Keytruda