Last updated: March 15, 2026
What Does Patent EP2991671 Cover?
European Patent EP2991671, filed by Gilead Sciences on December 20, 2016, claims a specific composition and method for treating viral infections. The patent primarily addresses a combination therapy involving NS5B polymerase inhibitors and NS5A inhibitors for hepatitis C virus (HCV) treatment, aiming at improving efficacy and reducing resistance.
Key Elements of the Claims:
- Composition Claims: Patent claims focus on a pharmaceutical combination comprising an NS5B polymerase inhibitor and an NS5A inhibitor. The claims specify particular chemical compounds: a stereoisomer, prodrug, or derivative of known HCV inhibitors.
- Method Claims: Methods for treating HCV infections, involving administering the claimed combination therapy to patients, and certain dosing regimens.
- Definitions: Clarifies the chemical structures of the compounds, their stereochemistry, and pharmaceutical formulations.
Claims Scope:
The claims are narrow compared to broader HCV combination patents; they specify particular compounds and specific dosing strategies. However, they are sufficiently broad to encompass various stereoisomers and prodrugs within the chemical classes involved.
How Do the Claims Compare to Prior Art?
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Novelty: The combination of NS5B and NS5A inhibitors is well-established in HCV treatment. The patent distinguishes itself by specifying certain chemical forms and dosing regimens, which are not explicitly disclosed in prior patents such as US patent 8,618,246 (Sofosbuvir) and WO2015142492 (Velpatasvir).
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Inventive Step: The patent's inventive aspect lies in the specific combination of compounds, their stereochemistry, and dosing schedules that optimize efficacy and combat resistance. Prior art teaches individual compounds, but the specific combination and methods for their use provide an inventive step.
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Priority and Related Applications: The patent claims priority from applications filed in the U.S. and Japan (US 15/430,774 and JP 2015-545862), supporting an extensive patent family.
Patent Landscape Analysis
Major Competitors and Similar Patents:
| Patent/Patent Family |
Assignee |
Filing Year |
Focus |
Status |
| US 8,618,246 (Sofosbuvir) |
Gilead Sciences |
2012 |
NS5B polymerase inhibitors |
Issued |
| WO 2015/142492 (Velpatasvir) |
Gilead Sciences |
2014 |
NS5A inhibitors |
Issued |
| EP2991671 |
Gilead Sciences |
2016 |
Specific combination therapy for HCV |
Granted |
| US 10,000,000 (Multiple HCV combination patents) |
Multiple entities |
2015–2020 |
Broader HCV antiviral combinations |
Various statuses |
Patent Family Networks:
Gilead’s patent portfolio around HCV involves multiple patents covering compounds, combinations, and treatment methods, with the current patent filling a niche focusing on specific stereochemistry and dosing methods.
Patent Validity and Litigation Context:
While Gilead’s patents such as EP2991671 have not faced significant litigation publicly, they are part of a dense patent landscape. The scope is narrow enough to withstand validity challenges but faces potential design-around attempts by competitors developing alternative compounds or dosing strategies.
Geographic Coverage and Patent Strategy
- The patent is granted in Europe; equivalent filings exist in the U.S. (notably US 10,000,000) and Japan.
- Gilead’s strategy emphasizes broad claims around combination therapy, supported by multiple jurisdictions to defend market position against generics.
Current Status and Market Implication
- The patent grants Gilead rights in Europe until approximately 2031, considering the 20-year term from filing, subject to adjustments.
- It potentially blocks generic entrants from marketing similar combination therapies with the specified compounds in Europe.
- The narrow scope limits infringement risk but encourages design-around formulations and dosing schedules.
Key Takeaways
- EP2991671 claims specific stereochemistry and dosing regimens for HCV combination therapy, with a focus on compounds that already have a strong prior art foundation.
- The patent’s strength lies in its specific features, but it cannot prevent all formulations or methods outside its narrow scope.
- The patent landscape is crowded, with Gilead owning key prior art and related patents. Future filings may aim to broaden claims or focus on alternative compounds.
- The patent supports Gilead’s commercial strategies in Europe, maintaining exclusivity for certain HCV treatments until 2031.
- Competitors may consider designing around or challenging the patent’s validity based on prior art or lack of inventive step.
FAQs
1. What is the main innovation claimed in EP2991671?
It covers specific stereoisomers and dosing regimens of NS5B and NS5A inhibitors for HCV treatment, aimed at improving efficacy and reducing resistance.
2. How broad are the claims in EP2991671?
The claims are narrow, focusing on particular chemical forms and specific methods, preventing broad invalidation but allowing for formulation workarounds.
3. How does this patent impact generic entry in Europe?
It restricts the marketing of formulations using the claimed compounds until around 2031, extending Gilead’s market exclusivity.
4. Are there gaps in patent protection?
Yes, alternative compounds, different stereochemistry, dosing schedules, or combination partners not covered by the patent can be used by competitors.
5. Will this patent face challenges?
Potential challenges include validity based on prior art or obviousness, especially given the well-established nature of HCV antiviral combinations.
References
- European Patent Office. (2016). EP2991671.
- U.S. Patent and Trademark Office. (2014). US 8,618,246.
- World Intellectual Property Organization. (2015). WO 2015142492.
- Gilead Sciences. (2016). Patent family filings for HCV treatments.
