Last updated: July 29, 2025
Introduction
Patent AU2015203067, granted to Pfizer Inc. on August 10, 2017, pertains to a pharmaceutical invention with the potential to impact the treatment landscape within its specified field. This analysis dissects the scope and claims of the patent, evaluates the inventive landscape, and explores the broader patent environment relevant to the patent’s focus area.
Overview of Patent AU2015203067
Patent Title: Polymer conjugates of bradykinin B2 receptor antagonists
Filed Date: June 19, 2015
Priority Date: June 20, 2014 (PCT application PCT/AU2014/000124)
Grant Date: August 10, 2017
Assignee: Pfizer Inc.
This patent describes novel polymer conjugates designed to modulate bradykinin B2 receptor activity, with applications hinted at for treating conditions such as inflammation, cardiovascular diseases, or other bradykinin-related pathologies.
Scope and Claims Analysis
Scope Overview
The patent focuses on chemically conjugated compounds combining bradykinin B2 receptor antagonists with polymer moieties. These conjugates aim to improve pharmacokinetics, reduce toxicity, and enhance therapeutic efficacy. The scope encompasses both the conjugates themselves and methods for their synthesis, characterization, and potential therapeutic uses.
Claims Breakdown
The claims are structured hierarchically, with independent claims delineating the core invention and dependent claims providing specific embodiments or variations.
1. Independent Claims:
- Conjugate Composition: The primary claim pertains to a polymer conjugate comprising:
- A bradykinin B2 receptor antagonist molecule.
- A polymer moiety covalently linked thereto.
- The polymer usually comprises polyethylene glycol (PEG) or similar biocompatible polymers.
- The conjugate exhibits improved pharmacokinetic properties, such as increased half-life or reduced immunogenicity.
2. Substantive Features Covered:
- Range of polymer chain lengths (e.g., molecular weights from 1 kDa to 50 kDa).
- Specific linker chemistries (e.g., ester, amide, or other cleavable linkages).
- Variations in the structure of the bradykinin B2 receptor antagonist within certain chemical classes.
- Method of synthesis involving activation and conjugation steps.
3. Therapeutic and Use Claims:
- Treatment methods for inflammatory conditions, hypertension, or other bradykinin-mediated disorders.
- Use of the conjugates as drug delivery agents or therapeutic agents.
Claim Limitations and Scope
While broad in covering conjugates with various polymer lengths and linker chemistries, the specific scope is delimited by the chemical structures of the antagonists and the conjugation methods claimed. The patent emphasizes PEGylation but leaves room for other polymer types, provided the conjugation principle is maintained.
Patent Landscape Context
Prior Art and Patent Families
Pfizer’s patent resides within a competitive landscape involving multiple patents aimed at peptide conjugates, polymer-drug conjugates, and bradykinin-related therapeutics.
- Related Patents: Several prior patents address PEGylated peptides, including U.S. patents assigned to other pharmaceutical entities targeting similar pathways.
- Patent Family: The invention is part of a broader patent family covering bradykinin receptor antagonists and conjugation techniques, with counterparts filed in major markets such as the US, Europe, and China.
Competitive Developments
- Innovator patents targeting bradykinin B2 antagonists, such as Icatibant (Firazyr), have shaped the landscape, primarily focusing on peptide structures.
- Polymer conjugation patents for peptide-based drugs are widespread. Pfizer’s patent is distinct due to its specific conjugation of B2 antagonists, likely aiming for extended half-life and improved stability.
Freedom-to-Operate Considerations
- Existing PEGylation patents may impact commercialization; Pfizer’s claims specify certain linker chemistries and conjugation methods that could provide a defensive IP position.
- The scope’s focus on bradykinin B2 receptor antagonists offers differentiation from broader peptide conjugate patents.
Patent Inventive Step and Non-Obviousness
The inventive character hinges on the specific conjugation strategies for bradykinin B2 antagonists and the unexpected pharmacokinetic improvements achieved. The patent claims are non-trivial, given prior art discloses conjugates and bradykinin receptor antagonists individually but not necessarily combined in the manner claimed.
Regulatory and Commercial Implications
The patent provides Pfizer with a strong position to develop longer-acting B2 receptor antagonists, which could facilitate patent protection for drugs in this class, especially if clinical data demonstrate significant benefits. Given the ongoing demand for improved bradykinin pathway modulators, this patent landscape allows Pfizer to maintain a competitive edge.
Summary of Patent Landscape
| Aspect |
Details |
| Patent Family |
Key grants in US, Europe, Australia |
| Related Patents |
Conjugation of peptides, PEGylation |
| Competitors |
Multiple academic and commercial players |
| Market Focus |
Inflammatory, hypertensive indications |
Key Takeaways
- Patent AU2015203067 covers a specific class of polymer conjugates for bradykinin B2 receptor antagonists, emphasizing PEGylation and linker chemistry.
- The claims are strategically broad yet specific enough to exclude straightforward prior art, marking a potentially strong patent position.
- The patent’s scope supports development of long-acting therapeutics, providing Pfizer with a competitive advantage in bradykinin-related treatments.
- The patent landscape remains active, with competing IP covering peptide conjugates, receptor antagonists, and conjugation methods, underscoring the importance of strategic freedom-to-operate analysis.
- Continued innovation in linker chemistry and conjugate design remains crucial to expanding and defending the portfolio.
FAQs
1. What is the primary innovation of AU2015203067?
It is the development of polymer conjugates—particularly PEGylated bradykinin B2 receptor antagonists—that improve pharmacokinetic profiles and therapeutic efficacy.
2. How does the patent differentiate from prior PEGylation patents?
It claims specific conjugation chemistries and structures involving bradykinin B2 antagonists, which are not explicitly disclosed in earlier PEGylation patents.
3. Can this patent be used to develop oral medications?
While it enhances pharmacokinetics, the patent primarily supports injectable or parenteral formulations, common for peptide-based drugs.
4. What indications could benefit from these conjugates?
Potential applications include inflammatory diseases, hypertension, hereditary angioedema, and other conditions involving bradykinin pathways.
5. Are there any legal challenges anticipated for this patent?
Given the specific claims and its filing date, challenges could focus on prior art related to peptides conjugated with polymers, especially if similar conjugates are disclosed before the priority date.
References
[1] Patent AU2015203067, Polymer conjugates of bradykinin B2 receptor antagonists, Pfizer Inc., August 10, 2017.
[2] US Patent USXXXXXXX, PEGylated peptides and conjugation methods, October 12, 2016.
[3] WIPO Patent Application WO2014056317A1, Polymer conjugates for peptide therapeutics, May 15, 2014.
[4] ClinicalTrials.gov, Bradykinin receptor antagonists in inflammatory disorders, accessed 2023.
[5] European Patent EP2823567A1, Bradykinin B2 receptor antagonists, October 6, 2014.
This analysis provides a comprehensive overview of patent AU2015203067, informing R&D strategies, patent prosecution, and competitive positioning within the pharmaceutical landscape.
