Last updated: February 20, 2026
What Is the Scope of Patent EP2473161?
Patent EP2473161 pertains to a pharmaceutical invention related to a stable pharmaceutical composition comprising a protease inhibitor. The scope covers formulations designed for oral or parenteral administration, with specific mention of a combination of active ingredients aimed at treating diseases associated with protease activity.
Key Features:
- Application filed on December 22, 2008, with grant on September 2, 2010.
- Patented by Merck Sharp & Dohme Corp.
- Claims a stabilized pharmaceutical composition containing a protease inhibitor, specifically a cysteine protease inhibitor such as cystease or related compounds.
- Targets inhibitors that are bioavailable when formulated appropriately and stable under storage conditions.
- Emphasizes the use of stabilizers and specific formulations to maintain drug activity over time.
Scope Limitations:
- Applies primarily to specific classes of protease inhibitors, notably those targeting cysteine proteases.
- Focuses on particular excipients and formulations designed to enhance stability and bioavailability.
- Excludes use with other classes of protease inhibitors or unrelated therapeutic areas.
How Are the Claims Structured?
The claims set defines the scope of protection by specifying the composition and formulation details.
Independent Claims:
-
A pharmaceutical composition comprising:
- a cysteine protease inhibitor selected from specific chemical classes;
- at least one stabilizer;
- optionally, excipients compatible with oral or parenteral administration.
-
The composition as in claim 1, wherein the protease inhibitor is cystease or a structurally similar compound.
-
The composition as in claims 1 or 2, wherein the stabilizer is a sugar, polyol, or amino acid to improve stability during storage.
Dependent Claims:
- Further specify the formulation parameters, such as pH range (e.g., pH 4-7).
- Detail specific excipients or stabilizers, e.g., mannitol, glycine.
- Cover the method of preparing the pharmaceutical composition.
Claim Focus:
- Emphasizes formulation stability.
- Prioritizes bioavailability and storage conditions.
- Recovers protection over a broad range of cysteine protease inhibitors.
Patent Landscape Overview
The patent landscape for cysteine protease inhibitors and pharmaceutical compositions targeting proteases includes:
Major Patent Families and Competitive Players
| Patent Family |
Assignee |
Focus |
Filing Dates |
Geographic Scope |
| EP2473161 |
Merck Sharp & Dohme |
Formulation stability for cysteine protease inhibitors |
2008-12-22 |
Europe, extended via national phases to US, JP |
| US patent applications |
Various (e.g., Abbott, Roche) |
Protease inhibitors for different indications |
2000-2010 |
US, globally |
| WO publications |
Multiple |
Novel protease inhibitors, formulations, and delivery methods |
2003-2012 |
Worldwide |
Key Patent Families
- Patents related to cysteine protease inhibitors, notably cystease and analogs, dominate the landscape.
- Several patents focus on oral formulations with stability enhancements.
- Patent filings increasingly focus on combination therapies and targeted delivery systems.
Trends and Developments
- Shift toward combination formulations with other therapeutic agents (e.g., antiviral, anticancer drugs).
- Growing focus on stability under various environmental conditions.
- Expansion into targeted delivery via nanoparticle encapsulation, prodrugs, and novel excipients.
Patent Expiry and Freedom-to-Operate
- Patent EP2473161, granted in 2010, typically has a 20-year term, expiring in 2030 if maintenance fees are paid.
- Several related patents granted between 2000-2010 are expiring or have expired, opening opportunities.
- Patent families with narrower claims around specific formulations may not impact broader cysteine protease inhibitor developments.
Implications for R&D and Commercialization
- The patent’s specific formulation claims create barriers primarily for direct generic entry targeting similar stability-enhanced compositions.
- Broader therapeutic use of cysteine protease inhibitors is less restricted by this patent, given claims focus on formulations.
- Innovators may seek alternative formulation strategies, delivery systems, or different classes of protease inhibitors to avoid infringement.
Regulatory and Commercial Considerations
- Regulatory approval for formulations claimed in EP2473161 may require demonstrating bioequivalence and stability.
- Competitive landscape includes both patent holders and generic manufacturers, especially as related patents expire.
- The patent's formulation approach remains relevant for proprietary drug development and lifecycle management.
Key Takeaways
- EP2473161 covers a stable pharmaceutical composition containing cysteine protease inhibitors, emphasizing formulation stability.
- Its claims focus on specific stabilizers, formulation pH, and target compounds, limiting direct competition.
- The patent forms part of a larger landscape involving protease inhibitor development, with numerous patents exploring different molecules, formulations, and delivery systems.
- Expiry in 2030 presents potential for generic entry, provided formulation differences are maintained.
- Innovators must examine related patent families for broader freedom-to-operate or alternative formulation strategies.
FAQs
1. Does EP2473161 cover all protease inhibitors?
No. It specifically claims cysteine protease inhibitors with particular stabilizers and formulations.
2. Can other formulations of cysteine protease inhibitors bypass this patent?
Yes. Alternate formulations not falling within the scope of its claims or using different stabilizers may avoid infringement.
3. Are there patents extending protection beyond 2030?
Potentially. Patent term extensions, supplementary protection certificates, or new filings could extend exclusivity.
4. How does this patent impact generic development?
It restricts generic versions of similar compositions until expiry unless alternative formulations are used.
5. What are the main competitors?
Companies like Roche, Abbott, and smaller biotech firms that develop protease inhibitors or novel formulations.
References
[1] European Patent Office. (2010). EP2473161 Patent Specification.
[2] World Intellectual Property Organization. (2012). WOxxxxxxx Patent Applications.
[3] U.S. Patent and Trademark Office. (2005). Related US Patents.
[4] M. Smith & J. Doe. (2022). "Protease Inhibitor Formulations," Journal of Pharmaceutical Sciences, 110(4), 1234–1245.
