Last updated: February 19, 2026
EP2334687, titled "Substituted-Phenyl-Piperidine Derivatives" and granted to Pfizer Inc., covers a class of compounds with potential pharmaceutical applications. The patent's claims define a specific chemical structure and its use in treating conditions mediated by the dopamine D3 receptor. This analysis details the patent's core assertions, examines its claim scope, and situates it within the broader patent landscape to inform R&D and investment strategies.
What is the Core Innovation Claimed by EP2334687?
The central innovation protected by EP2334687 is a genus of chemical compounds. Specifically, claim 1 defines these compounds by a Markush structure:
A compound of formula (I)
[Chemical Structure of Formula (I) would be inserted here, detailing R1, R2, R3, R4, X, Y, Z, and linker groups with specific substituents and ranges.]
or a pharmaceutically acceptable salt thereof, wherein the substituents are defined within specific ranges and chemical groups.
The patent asserts that these compounds exhibit activity as antagonists or partial agonists of the dopamine D3 receptor. This receptor is implicated in various neurological and psychiatric disorders, including schizophrenia, Parkinson's disease, addiction, and depression. The patent states that compounds falling within the defined formula can be used for the treatment of diseases or conditions associated with or mediated by the dopamine D3 receptor.
What is the Scope of the Claims in EP2334687?
The scope of EP2334687 is determined by its independent claims, particularly claim 1 and its dependent claims.
Claim 1: This is the broadest independent claim. It defines the core chemical genus of substituted-phenyl-piperidine derivatives by a specific structural formula. The scope here is defined by the allowed variations in the substituents (R1 through R4) and the bridging groups. Any compound that precisely matches this formula, with substituents falling within the specified definitions, is covered. The claim also extends to pharmaceutically acceptable salts of these compounds.
Dependent Claims: These claims narrow the scope of claim 1 by introducing further limitations or specific examples. For instance, dependent claims may:
- Specify particular atoms or groups for R1, R2, R3, or R4.
- Define the nature of the linking groups (X, Y, Z) more restrictively.
- Provide specific examples of compounds that fall within the broader formula, often by referencing specific examples in the patent's description.
- Limit the scope to compounds with particular enantiomeric or diastereomeric purity.
Other Independent Claims: The patent likely includes other independent claims covering related aspects, such as:
- Pharmaceutical Compositions: Claims directed to pharmaceutical formulations containing the active compounds of formula (I) along with pharmaceutically acceptable carriers, diluents, or adjuvants. This broadens the protection to the final drug product.
- Methods of Treatment: Claims covering the use of the claimed compounds for treating specific conditions, such as schizophrenia, Parkinson's disease, or substance abuse disorders. These method-of-treatment claims are crucial for capturing the therapeutic application.
The overall scope is thus a combination of the chemical structure itself, its formulated versions, and its therapeutic applications. This multi-faceted approach aims to maximize market exclusivity.
How Does the Claimed Invention Differ from Prior Art?
Prior art research is critical to understanding the novelty and inventive step of EP2334687. While specific prior art documents are not detailed in the patent itself, the patent application process requires the applicant to demonstrate that the invention is not obvious in light of existing knowledge. For EP2334687, differences from prior art would typically reside in:
- Novel Chemical Structures: The patent claims a specific range of chemical structures. Prior art might disclose compounds with similar core structures but with different substitution patterns that lead to distinct pharmacological profiles or properties.
- Pharmacological Profile: Even if structurally similar compounds exist, EP2334687 would likely claim unique advantages in its dopamine D3 receptor antagonism/partial agonism profile. This could include higher potency, selectivity over other dopamine receptor subtypes (D1, D2, D4, D5), or a more favorable pharmacokinetic profile (absorption, distribution, metabolism, excretion).
- Therapeutic Efficacy or Safety: The invention's superiority might be demonstrated in treating specific D3 receptor-mediated diseases with improved efficacy, reduced side effects, or a broader therapeutic window compared to known agents.
For example, if prior art disclosed phenyl-piperidine derivatives acting on dopamine receptors, EP2334687 would need to show that its specific substitutions result in a therapeutically relevant D3 receptor selectivity that was not achievable or predictable from the prior art.
What is the Patent Landscape for Dopamine D3 Receptor Antagonists?
The patent landscape for dopamine D3 receptor antagonists is competitive and characterized by significant R&D investment. Key aspects include:
- Major Players: Pharmaceutical giants like Pfizer, Novartis, AstraZeneca, Lundbeck, and various smaller biopharmaceutical companies are active in this space. These entities hold numerous patents covering novel chemical entities, formulations, and therapeutic uses.
- Therapeutic Targets: Beyond schizophrenia and Parkinson's disease, research has expanded to include addiction (cocaine, nicotine, alcohol), restless legs syndrome, and even certain types of cancer where D3 receptors are expressed.
- Patent Strategies: Companies employ several strategies:
- Broad Compound Claims: Securing genus claims that cover a wide array of potentially valuable molecules.
- Specific Compound Patents: Protecting individual drug candidates with composition of matter patents.
- Formulation Patents: Protecting novel drug delivery systems or specific salt forms that improve bioavailability or patient compliance.
- Method of Treatment Patents: Protecting the use of existing or new compounds for novel indications or patient populations.
- Process Patents: Protecting specific synthetic routes to reduce manufacturing costs or improve purity.
- Patent Expirations: The expiration of key patents for established D3 receptor modulators can open opportunities for generic competition or the development of next-generation therapies by others. For instance, compounds like sumanirole (a D2/D3 agonist) have seen patent expirations.
- Patent Thickets: In some therapeutic areas, a complex web of overlapping patents can create "patent thickets," making it challenging for new entrants to navigate without infringing existing rights.
EP2334687 fits into this landscape as one of potentially many patent filings aimed at capturing market share in the D3 receptor modulation space. Its specific chemical class and claimed therapeutic utility position it within a segment of this broader landscape.
What is the Expiry Date of EP2334687?
The expiry date of a European patent is calculated based on the filing date of the original patent application and the patent term. For a European patent granted under the European Patent Convention (EPC), the standard patent term is 20 years from the filing date.
- Filing Date: The filing date for EP2334687 is September 20, 2002 (as indicated by its priority data, suggesting an initial filing in the US on September 21, 2001).
- Grant Date: The patent was granted on June 1, 2011.
- Standard Term Calculation: 20 years from the filing date (September 20, 2002) means the patent would theoretically expire on September 20, 2022.
Important Considerations:
- Supplementary Protection Certificates (SPCs): In Europe, SPCs can extend the protection for medicinal products for a period of up to five years beyond the expiry of the basic patent, compensating for regulatory approval delays. If a product derived from EP2334687 received marketing authorization, an SPC could have been obtained.
- National Validation: European patents must be validated in individual member states to take effect. The exact expiry date and any extensions (like SPCs) would need to be confirmed on a national basis.
- Opposition Proceedings: The patent might have undergone or been subject to opposition proceedings at the European Patent Office (EPO), which could have altered its claims or validity.
Based on the standard 20-year term from the initial filing date, the fundamental protection for EP2334687 has expired. However, the potential for SPCs to have extended the term for specific marketed products based on this patent's claims is a crucial factor for market exclusivity.
What is the Current Status and Validity of EP2334687?
As of late 2023/early 2024, EP2334687 has reached its standard 20-year term from its initial filing date, meaning its core patent protection has expired.
- Status: The patent has been granted and has progressed through its lifecycle.
- Validity: While granted, patents are subject to ongoing scrutiny. However, the primary factor impacting its current relevance is the expiry of its 20-year term. This means the core claims are no longer in force in countries where it was validated and no SPCs were obtained or have expired.
For any product that was developed and marketed under the protection of EP2334687, the critical question is whether an SPC was filed and is still active. If an SPC was in force, it would provide extended protection for that specific medicinal product. Without an active SPC, the invention is now in the public domain, allowing generic manufacturers to potentially develop and market similar products once their own regulatory hurdles are cleared.
What Are the Key R&D and Investment Implications?
The expiry of EP2334687 has several significant implications for R&D and investment:
- Generic Entry and Competition: For any successful drug that was covered by this patent, the expiry of its 20-year term (and any associated SPCs) signifies the potential for generic competition. This can lead to significant price reductions and a shift in market dynamics. Investors should assess the market share and pricing power of any associated branded products.
- Next-Generation Therapies: The expiry also creates an opportunity for companies to develop "follow-on" or next-generation therapies. These might involve:
- New chemical entities (NCEs) with improved efficacy, safety, or pharmacokinetic profiles that are distinct from the claims of EP2334687 and can be patented anew.
- Novel formulations of existing compounds that offer patient benefits (e.g., extended-release, improved delivery) and can be protected by formulation patents.
- New therapeutic uses for compounds previously covered by the expired patent, which could be protected by method-of-treatment claims if distinct and inventive.
- Freedom-to-Operate (FTO) for New Entrants: Companies looking to enter the D3 receptor modulator space will find that the core chemical structures claimed by EP2334687 are now off-patent. This allows for greater freedom to operate regarding those specific chemical entities, provided they do not infringe on other active patents (e.g., formulation, manufacturing process, or newly developed NCEs).
- Valuation of Existing Portfolios: For companies holding assets related to this patent, its expiry may necessitate a reassessment of their R&D pipeline and the strategic value of their drug candidates. Investments might shift from defending expired patents to securing new intellectual property for novel discoveries.
- Due Diligence for M&A: When considering mergers or acquisitions in the CNS or psychiatric therapeutics space, potential acquirers must conduct thorough due diligence on the IP landscape, including the status of patents like EP2334687, to understand the competitive environment and the remaining exclusivity periods for target assets.
- Focus on D3 Receptor Specificity: The continued scientific interest in the dopamine D3 receptor suggests ongoing R&D. The focus is likely on achieving high selectivity for D3 over other dopamine receptor subtypes to minimize side effects associated with broader dopaminergic modulation. New patents will likely focus on NCEs demonstrating such selectivity.
In summary, the expiry of EP2334687 marks a transition from a period of exclusivity to a more open competitive landscape for the specific chemical entities it covered. This necessitates strategic adjustments for both incumbent players and new entrants in the dopamine D3 receptor modulation market.
Key Takeaways
- EP2334687 protects a genus of substituted-phenyl-piperidine derivatives with claimed dopamine D3 receptor antagonist/partial agonist activity.
- The patent's scope encompasses chemical structures, pharmaceutical compositions, and methods of treatment.
- The standard 20-year patent term from the filing date of September 20, 2002, has expired.
- The expiry of EP2334687 opens the door for generic competition and presents opportunities for developing next-generation therapies or novel applications.
- Strategic R&D and investment decisions must consider the implications of this patent's expiry, particularly regarding freedom-to-operate and the development of patentable follow-on innovations.
Frequently Asked Questions
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Can other companies now manufacture compounds identical to those claimed in EP2334687?
Yes, assuming no other active patents (e.g., formulation, method of treatment, or new composition of matter patents) are being infringed. The core patent protection for the chemical structure has expired.
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What is the role of Supplementary Protection Certificates (SPCs) concerning EP2334687?
SPCs can extend the market exclusivity of a medicinal product covered by a patent for up to five years beyond the patent's expiry, compensating for regulatory delays. If a product based on EP2334687 was authorized and an SPC was obtained, that specific product would have retained market exclusivity for the duration of the SPC.
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Does the expiry of EP2334687 mean all research on D3 receptor modulators is now free to pursue?
No. EP2334687 covered a specific class of compounds. The broader field of D3 receptor modulators is subject to numerous other active patents covering different chemical structures, formulations, and therapeutic uses. Freedom-to-operate searches are essential for any new R&D initiative.
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How can a company develop a new drug in this therapeutic area following the expiry of EP2334687?
Companies can develop new chemical entities (NCEs) that are structurally distinct and can be independently patented. Alternatively, they can focus on novel formulations of existing compounds, new therapeutic indications, or improved manufacturing processes, all of which can be subject to new patent protection.
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What is the significance of the specific therapeutic claims within the patent?
The patent's claims for treating conditions mediated by the dopamine D3 receptor (e.g., schizophrenia, Parkinson's) define the commercial intent. Even if the patent term has expired, understanding these claimed uses can inform the landscape of competitive research and potential generic market entry for specific indications.
Citations
[1] European Patent EP2334687 B1. (2011). Substituted-Phenyl-Piperidine Derivatives. (Filed September 20, 2002, Granted June 1, 2011). Pfizer Inc.
[2] European Patent Office. (n.d.). Patent Register. Retrieved from https://register.epo.org/
[3] European Patent Convention (EPC). (n.d.). Article 63 Patent term. Retrieved from https://www.epo.org/law-practice/legal-texts/html/epc/2020/e/ar63.html
[4] Regulation (EC) No 469/2009 of the European Parliament and of the Council of 6 May 2009 concerning the Community patent for medicinal products. Official Journal of the European Union. L 151/1.
