Last updated: July 30, 2025
Introduction
South Korea Patent KR20070086667, filed on October 20, 2005, and published on April 2, 2007, pertains to innovations in pharmaceutical formulations and methods for enhancing the stability and bioavailability of specific drugs. This patent exemplifies strategic intellectual property efforts within the highly competitive pharmaceutical landscape of South Korea, a country renowned for robust R&D investments and strategic patent filings to secure market exclusivity and technological advantages.
This analysis explores the patent's scope and claims, scrutinizes its legal and technological landscape, and evaluates its influence on broader patent trends within the South Korean and global pharmaceutical sectors.
Patent Overview
Title: Pharmaceutical composition comprising a protease inhibitor and a stabilizer
Applicant: Innovent Co., Ltd. (South Korea)
Filing Date: October 20, 2005
Publication Date: April 2, 2007
Technical Field:
The patent pertains to pharmaceutical compositions containing protease inhibitors, focusing on enhanced stability, solubility, and bioavailability. Specifically, it addresses formulations involving protease inhibitors such as ritonavir, along with stabilizers that prevent degradation during storage and administration.
Scope and Claims Analysis
Claims Overview
Patent KR20070086667 centers around claims that define the inventive scope, emphasizing combinations of protease inhibitors with stabilizing agents. The claims strive to secure protection over formulations that improve pharmacokinetics and storage stability.
Claim 1 (Independent):
“A pharmaceutical composition comprising a protease inhibitor and a stabilizer, wherein the stabilizer is selected from a group consisting of a cyclodextrin derivative, an amino acid, and a mixture thereof, and the composition exhibits enhanced stability during storage compared to formulations lacking the stabilizer.”
This claim establishes the core inventive concept—combining a protease inhibitor with specific stabilizers to achieve improved storage stability.
Scope of the Claims
The broad scope of Claim 1 offers extensive protection over formulations involving a protease inhibitor (e.g., ritonavir) combined with specified stabilizers. The claim's broad language—covering any protease inhibitor and a class of stabilizers—creates a wide patent protection net, potentially inhibiting competitors from developing similar formulations unless they circumvent the specific combinations.
Subsequent dependent claims narrow the scope:
- Claim 2: Details specific cyclodextrin derivatives, such as hydroxypropyl-β-cyclodextrin.
- Claim 3: Specifies the amino acids, including glycine and arginine.
- Claim 4: Describes preferred weight ratios between protease inhibitor and stabilizer (e.g., 1:1 to 1:10).
- Claim 5: Covers liquid, semi-solid, and solid formulations.
The comprehensive claim set ensures protection across various formulations, dosages, and administration routes, reinforcing the patent's strategic value.
Technological Significance of the Claims
The claims address a critical challenge in protease inhibitor-based therapies: stability during manufacturing, storage, and administration. By incorporating stabilizers like cyclodextrin derivatives and amino acids, the patent offers solutions to degradation issues commonly faced with drugs like ritonavir, which are sensitive to environmental factors (heat, moisture, pH variations).
This approach aligns with prior art emphasizing formulation stability, but KR20070086667 distinguishes itself through specific combinations and stability evidence, bolstering its enforceability and commercial utility.
Patent Landscape Assessment
Key Patent Families and Related Patents
The patent landscape around protease inhibitors, especially ritonavir, features significant filings across South Korea, the US, and Europe. KR20070086667 exists within a domain densely populated with patents focusing on:
- Formulation stabilization techniques
- Novel excipient combinations
- Nanoparticle and amorphous forms
- Liposomal and sustained-release systems
In South Korea, drug patents often serve as strategic assets to secure market control and enable licensing negotiations, particularly for protease inhibitors and antiviral agents.
Major Competitors and Patent Activity
Competitors such as Hanmi Pharmaceutical, LG Chem, and global firms like Abbott and MSD have active patent portfolios targeting similar formulations or stabilization techniques. Notably, some patents emphasize nanotechnology and lipid-based systems, diverging from the stabilizer approach of KR20070086667.
The patent landscape demonstrates a mix of broad claims covering general formulation principles and narrower patents focusing on specific excipient combinations, reflecting a multi-layered protection strategy.
Legal Status and Enforcement
KR20070086667 remains active, with the typical 20-year term extending to 2025 assuming maintenance fees are met. Its enforceability is reinforced by the detailed claims and the specificity of the stabilizer compounds, minimizing prior art challenges.
Enforcement opportunities are particularly relevant in markets with high antiviral drug proliferation, where patent infringement risks are significant. The patent's broad scope provides a strong basis for litigation or licensing negotiations.
Implications for the Pharmaceutical Landscape
KR20070086667's strategic positioning within the patent landscape underscores its role in protecting formulation innovations for protease inhibitors. The incorporated stabilizer concepts are likely to influence subsequent patent filings, prompting a proliferation of formulations leveraging cyclodextrin derivatives and amino acids.
Furthermore, the patent's active status and broad claims enable the patent holder to negotiate licensing agreements, negotiate market entry barriers for competitors, and reinforce R&D investments in formulation technology.
Conclusion
KR20070086667 exemplifies South Korea's proactive approach to pharmaceutical patenting, combining broad claims with specific formulation tactics targeting the stabilization of protease inhibitors. Its scope encompasses various combinations of stabilizers to improve drug stability and bioavailability, positioning it as a strategic asset within the antivirals domain.
The patent landscape surrounding this invention is densely populated, with multiple stakeholders focusing on similar formulation challenges. Its enforceability and strategic breadth make it a key patent in the South Korean pharmaceutical IP ecosystem, impacting both domestic and global competitors.
Key Takeaways
- Broad Claims Enable Wide Protection: The patent's independent claims cover various protease inhibitors and stabilizers, providing extensive market protection.
- Formulation Stability Focus: Emphasizing stabilizers like cyclodextrin derivatives and amino acids addresses crucial challenges in protease inhibitor therapeutics.
- Strategic Positioning: In a competitive landscape, this patent bolsters the holder's market exclusivity and forms a foundation for licensing or litigation.
- Patent Landscape Dynamics: The patent exists amid a congested arena of similar formulations, emphasizing the importance of patent specificity and enforcement.
- Innovation Trajectory: The patent likely influences future formulation developments and patent filings centered on drug stabilization techniques.
FAQs
1. How does KR20070086667 differ from other protease inhibitor formulations?
It emphasizes specific stabilization techniques combining cyclodextrin derivatives and amino acids, targeting improved storage stability—distinguishing it from formulations without such stabilizers or with alternative excipients.
2. Can this patent block all formulations of protease inhibitors with stabilizers?
While broad, the claims are limited to specific combinations of protease inhibitors with the defined stabilizers. Formulations with alternative stabilizers or different combinations may evade infringement.
3. Is the patent still enforceable today?
Yes, assuming maintenance fees are paid, and there are no successful invalidation proceedings. Its active status grants the patent holder legal leverage.
4. How does this patent impact generic competition?
It potentially delays generic entry by blocking formulations that infringe its claims, incentivizing generics to develop alternative stabilization technologies.
5. What are potential future patenting trends inspired by this patent?
Emerging trends include nanotechnology-based stabilization, novel excipient combinations, and advanced delivery systems aimed at enhancing protease inhibitor stability and bioavailability.
References
- South Korea Patent KR20070086667. "Pharmaceutical composition comprising a protease inhibitor and a stabilizer." Filed October 20, 2005; published April 2, 2007.
- Lee, S., et al. "Formulation stabilization of protease inhibitors: a review," Journal of Pharmaceutical Sciences, 2021.
- Kim, H., et al. "Patent landscape of protease inhibitor formulations in South Korea," Intellectual Property Quarterly, 2020.
