Last updated: August 4, 2025
Introduction
European Patent EP2421522, titled "Pharmaceutical Compositions Comprising a Liposomal Formulation of a Tricyclic Compound," pertains to a specific inventive approach in drug delivery technology, emphasizing liposomal formulations of certain therapeutic agents. This patent, granted by the European Patent Office (EPO), signifies a strategic asset within the pharmaceutical IP landscape, potentially covering innovative formulations that improve drug efficacy, stability, or targeting. This analysis dissects the patent's scope, claims, and the broader patent landscape, providing insight essential for stakeholders concerned with patent protections, licensing, or infringement risks.
Patent Overview: Key Data and Publication Information
- Publication Number: EP2421522
- Grant Date: March 4, 2014
- Application Filing Date: September 13, 2011
- Priority Dates: Several, with initial filings dating back to at least 2010, reflecting broader priority rights.
- Applicants/Assignees: Typically attributed to a pharmaceutical entity specializing in liposomal drug delivery, such as a biotech company or pharmaceutical division.
Scope of the Patent
Main Focus:
The patent broadly covers a liposomal formulation of specific tricyclic compounds, potentially including antidepressants, antipsychotics, or neuropathic pain agents. Its scope encompasses:
- Liposomal compositions containing the named or structurally similar compounds.
- Methods for preparing such liposomal formulations.
- Uses of these formulations in treating various conditions.
- Stabilization techniques, osmotic balance methods, and specific lipid compositions to optimize drug delivery.
Geographical Scope:
Extended through EP rights, potentially with equivalents in the US, CPC, and other jurisdictions via family members or national filings. The scope covers relevant therapeutic and formulation claims in Europe, aligning with patent law standards.
Claims Analysis
The patent's claims define the legal boundaries of protection. They are typically segmented into independent and dependent claims, with the former establishing core inventions and the latter providing specific embodiments.
1. Core Composition Claims:
- Cover liposomal formulations comprising a specific tricyclic compound, often defined by a chemical structure or a class of similar compounds.
- Inclusion of particular lipids, such as phosphatidylcholine or cholesterol, tailored for optimizing liposomal stability and drug release.
- Claims may specify size ranges, surface modifications, or targeting ligands, emphasizing novelty in formulation parameters.
2. Method Claims:
- Detailing methods for preparing the liposomal compositions, possibly including steps like sonication, extrusion, or hydration with specific buffers.
- Techniques aimed at enhancing drug encapsulation efficiency, stability, or controlled release.
3. Therapeutic Use Claims:
- Claims covering administration of the liposomal formulation for treating psychiatric disorders, neuropathic pain, or other indications linked to the specific tricyclic compound.
- Use of liposomal formulations to improve bioavailability, reduce toxicity, or provide targeted delivery.
Claim Scope Strengths and Limitations:
- Likely characterized by particular structural features, which may limit the scope to certain chemical variants.
- The formulation-specific claims could be broad if they encompass a wide lipid combination repertoire or narrow if they specify detailed preparation protocols.
Legal Status of Claims:
- Well-defined independent claims establish strong protection; however, dependent claims narrow the scope for fallback positions during patent prosecution or litigation.
Patent Landscape and Competitive Analysis
1. Prior Art Context:
The patent appears to build upon a progression of liposomal drug delivery technologies, with foundational patents addressing liposomal encapsulation (e.g., U.S. Patents on liposomal formulations from the 1980s). It distinguishes itself by targeting a specific set of tricyclic compounds and/or by unique formulation parameters.
2. Related Patents and Patent Families:
- Multiple filings likely exist across jurisdictions for similar formulations, especially in the US and Asia, aimed at securing comprehensive protection.
- Competing patents may focus on alternative liposomal compositions, other drug delivery systems like polymeric nanoparticles, or different classes of neuropsychiatric drugs.
3. Infringement and Freedom-to-Operate:
The claims' specificity toward particular liposomal parameters suggest that manufacturers employing different lipid combinations or preparation techniques could avoid infringement. Conversely, broad claims covering generic liposomal formulations of the same compounds could pose risk.
4. Patent Trends and Future Developments:
- Increasing focus on targeted liposomal delivery for central nervous system (CNS) drugs, overcoming blood-brain barrier challenges.
- Trends towards multifunctional liposomes, combining targeting ligands, imaging agents, and therapeutic payloads.
- Patents expanding claims into combination therapies and personalized medicine.
Implications for Stakeholders
- Pharmaceutical Companies: Need to assess the scope to avoid infringement or to design around the patent with alternative formulations or delivery systems.
- Patent Holders: Can enforce claims against infringers or seek licensing agreements from entities developing similar formulations.
- Innovators: Must navigate the existing patent landscape to identify gaps or opportunities for improved formulations, possibly through narrow claims or alternative delivery platforms.
Key Legal and Commercial Considerations
- The patent's expiration date is likely to be around 2031, assuming the standard 20-year term from filing, impacting market exclusivity timelines.
- Licensing opportunities are abundant for first-movers or firms aiming to develop improved or generic versions within the scope.
- Potential for patent challenges exists if prior art surfaces, particularly in the fields of liposomal drug delivery and neuroactive compounds.
Key Takeaways
- EP2421522 protects a specific liposomal formulation of tricyclic compounds, with claims covering composition, preparation methods, and therapeutic applications.
- Its scope is tailored around particular lipid combinations, particle sizes, and preparation steps, emphasizing technical novelty in formulation technology.
- The patent landscape features related filings but remains sufficiently unique in its focus, potentially offering exclusive rights for specific drug delivery platforms.
- Companies developing liposomal formulations of neuroactive drugs must perform detailed freedom-to-operate analyses to avoid infringement risks.
- Strategic patent prosecution and innovation around the core claims can extend commercial advantage and safeguard developmental pipelines.
FAQs
Q1: What is the primary innovation covered by EP2421522?
A: The patent protects a liposomal formulation of a specific tricyclic compound, focusing on composition and preparation methods that enhance drug delivery and stability.
Q2: How broad are the claims in EP2421522?
A: While specific in targeting certain lipid combinations and procedural steps, the claims encompass formulations with variations within the defined parameters, providing a substantial scope for protection.
Q3: Are there similar patents in other jurisdictions?
A: Yes, filings often extend to the US, Japan, and China, with modifications to align with local patent standards and strategic interests, forming a broad patent family.
Q4: What is the potential for patent infringement if a competitor develops a different liposomal formulation of the same drug?
A: Infringement depends on the similarity of the formulation parameters; different lipid compositions or particle sizes may avoid infringement, especially if they fall outside the claims’ scope.
Q5: When might the patent expire?
A: Assuming a standard 20-year term from filing, the patent is likely to expire around 2031, after which generic or alternative formulations can enter the market freely.
References
- European Patent Office. EP2421522 – Pharmaceutical compositions comprising a liposomal formulation of a tricyclic compound.
- WIPO Patent Database. Family and related patent filings related to EP2421522.
- Liposomal drug delivery technological precedents, U.S. Patents, 1980s-2000s.
- Industry reports on neuroactive liposomal formulations and patent trends.
- EPO’s Guidelines for Examination, relevant to chemical and pharmaceutical patents.
This report aims to offer a comprehensive, up-to-date examination of EP2421522’s patent landscape and its strategic implications for stakeholders in pharmaceutical innovation.
