Last updated: February 19, 2026
This analysis details the scope and claims of Australian patent AU2003244799, focusing on its patent landscape and implications for drug development and investment. The patent, granted on May 19, 2005, to Bristol-Myers Squibb Company, covers compounds and their use in treating inflammatory diseases.
What is the Core Invention Protected by AU2003244799?
The patent protects certain substituted heterocyclic compounds. Specifically, it claims compounds of Formula (I) and related structures, where R1, R2, R3, R4, and R5 are defined substituents, and Ar is a defined aryl group. These compounds act as inhibitors of specific inflammatory signaling pathways, primarily targeting phosphodiesterase (PDE) enzymes, such as PDE4.
Formula (I):
R2
|
Ar--C--N--R3
| |
R1 R4
- Ar: Defined aryl group, often substituted.
- R1: Typically hydrogen or a leaving group.
- R2: Various substituents, including alkyl, cycloalkyl, or aryl groups.
- R3: Hydrogen, alkyl, or other specified groups.
- R4: Hydrogen, alkyl, or other specified groups.
The claims extend to pharmaceutically acceptable salts, solvates, and prodrugs of these compounds. The patent also covers pharmaceutical compositions containing these active compounds, and methods of treating inflammatory conditions.
What Specific Therapeutic Indications are Covered?
The patent claims methods of treating inflammatory diseases by administering the claimed compounds. This broad categorization encompasses a range of conditions where chronic inflammation plays a significant role.
Specific Indications Claimed:
- Arthritis: Including rheumatoid arthritis and osteoarthritis.
- Asthma: A chronic inflammatory airway disease.
- Chronic Obstructive Pulmonary Disease (COPD): Characterized by persistent inflammation of the lungs.
- Inflammatory Bowel Disease (IBD): Such as Crohn's disease and ulcerative colitis.
- Psoriasis: A chronic autoimmune condition causing skin inflammation.
- Atopic Dermatitis: A type of eczema.
- Allergic Rhinitis: Hay fever.
The patent asserts that the compounds achieve therapeutic effects by modulating the levels of cyclic nucleotides, such as cyclic adenosine monophosphate (cAMP), within cells. PDE enzymes, particularly PDE4, are known to degrade cAMP. Inhibiting these enzymes leads to increased intracellular cAMP levels, which can suppress the inflammatory response.
What are the Key Claims in AU2003244799?
The patent's claims define the legal boundaries of the invention. These claims are structured hierarchically, with independent claims providing the broadest protection and dependent claims narrowing the scope.
Independent Claims of Significance:
- Claim 1: This is the primary claim defining the compounds of Formula (I) and specific subclasses thereof. It encompasses a wide range of structural variations, providing broad protection for the core chemical entities. The substituents are defined with specific functional groups and ranges. For example, Ar is described as a substituted phenyl group, and R2 can be a substituted alkyl group, allowing for a large number of potential compound variations.
- Claim 12: This claim covers a pharmaceutical composition comprising a compound of Claim 1 or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier. This protects the formulation of the drug.
- Claim 14: This claim relates to a method of treating an inflammatory disease in a subject, comprising administering to the subject an effective amount of a compound of Claim 1 or a pharmaceutically acceptable salt thereof. This protects the therapeutic use of the compounds.
Dependent Claims (Examples):
Dependent claims refine the scope of the independent claims by adding specific limitations. For instance, they might specify particular substituents for Ar, R2, R3, or R4, or limit the class of inflammatory diseases to be treated. These claims are crucial for reinforcing protection and covering specific embodiments that might otherwise be considered less central to the core invention.
What is the Patent Landscape for PDE4 Inhibitors in Australia?
The patent landscape for PDE4 inhibitors is complex, characterized by a significant number of patents filed by various pharmaceutical companies. Bristol-Myers Squibb has been an active player in this field.
Key Characteristics of the PDE4 Inhibitor Landscape:
- Early Pioneer Patents: Initial patents in this area focused on the fundamental discovery of PDE4 inhibition and its therapeutic potential.
- Structure-Activity Relationship (SAR) Patents: Subsequent patents often cover specific chemical classes or novel scaffolds that demonstrate improved efficacy, selectivity, or reduced side effects compared to earlier compounds.
- Formulation and Delivery Patents: Protection is also sought for specific drug delivery systems, formulations (e.g., sustained-release), and combinations with other therapeutic agents.
- Method of Use Patents: Patents claiming specific therapeutic applications or patient populations for PDE4 inhibitors are common.
- Generic Competition: As patents expire, generic manufacturers can enter the market. However, the complex chemistry and therapeutic applications mean that overlapping patent protection can still create barriers.
AU2003244799 is one of many patents within this broader landscape. Its strength lies in its broad chemical claims covering a significant class of PDE4 inhibitors. However, its validity and enforceability can be challenged by prior art or by the existence of other patents covering similar structures or uses.
What is the Filing and Grant History of AU2003244799?
Understanding the timeline of a patent is essential for assessing its remaining term and potential for market exclusivity.
- International Application Number: PCT/US2003/033578
- International Filing Date: October 23, 2003
- Priority Date: October 24, 2002 (US Application No. 10/279,722)
- Australian National Phase Entry Date: April 23, 2004
- Publication Date: July 1, 2004 (as WO2004/056809)
- Grant Date: May 19, 2005
- Patent Expiry Date: October 24, 2022 (20 years from the priority date).
The patent is now expired in Australia.
What are the Implications of AU2003244799 for R&D and Investment?
The expired status of AU2003244799 means that the specific compounds and methods claimed are now in the public domain in Australia, subject to any other overlapping patent protections that might still be in force.
Implications for R&D:
- Freedom to Operate: Companies can now research, develop, and commercialize compounds falling within the scope of AU2003244799's expired claims without infringing this specific patent. This opens avenues for developing next-generation PDE4 inhibitors or repurposing previously patented compounds.
- Focus on Novelty: R&D efforts will need to focus on creating compounds with novel chemical structures or distinct therapeutic advantages not covered by other, potentially still-active patents. This includes targeting different PDE isoforms, improving pharmacokinetic profiles, or addressing unmet medical needs within inflammatory diseases.
- Development of Improved Formulations: The expired claims do not prevent the development of new and improved pharmaceutical compositions and delivery systems for the claimed compounds.
Implications for Investment:
- Increased Competition: The expiration of key patents can lead to increased competition, potentially impacting pricing and market share for existing therapies.
- Opportunity for Generic Manufacturers: Generic drug companies can now seek to produce and market bioequivalent versions of any drugs that were exclusively protected by AU2003244799, provided no other patents exist.
- Investment in New Entities: Investors may shift their focus towards companies developing novel PDE4 inhibitors or drugs for inflammatory diseases with strong, unexpired patent protection and clear clinical differentiation. The expired patent signals a mature segment of the market.
- Due Diligence on Remaining IP: For any existing or potential drug product related to this class of compounds, thorough due diligence on all other relevant active patents (composition of matter, method of use, formulation) is critical before making investment decisions.
Key Takeaways
- Australian patent AU2003244799, now expired, protected specific substituted heterocyclic compounds acting as PDE4 inhibitors for inflammatory diseases.
- The patent's claims covered a broad class of chemical entities and their therapeutic applications, including arthritis, asthma, and COPD.
- The patent expired on October 24, 2022, removing its exclusive protection in Australia.
- The expiration facilitates freedom to operate for R&D in this chemical space, but investment decisions require careful evaluation of any remaining active patents in the PDE4 inhibitor landscape.
Frequently Asked Questions
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Does the expiration of AU2003244799 mean all PDE4 inhibitors are now free to be manufactured and sold in Australia?
No. While this specific patent has expired, other patents covering different chemical structures, specific formulations, or distinct methods of use for PDE4 inhibitors may still be in force. A comprehensive patent landscape analysis is required.
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What were the primary compounds or classes of compounds protected by this patent?
The patent protected compounds of Formula (I) and related structures, which are substituted heterocyclic compounds designed to inhibit PDE4 enzymes.
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What is the significance of the priority date of this patent?
The priority date (October 24, 2002) establishes the earliest date for novelty and inventive step for the invention. The patent term is calculated from this date, meaning the patent protection lasted for 20 years from October 24, 2002.
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Can companies now develop generic versions of drugs previously protected by AU2003244799?
If a specific drug product was exclusively covered by the expired claims of AU2003244799 and no other valid patents are in force, then generic versions could be developed. However, the presence of other patents can prevent this.
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What are the key inflammatory diseases that this patent aimed to treat?
The patent claimed methods of treating a range of inflammatory diseases, including rheumatoid arthritis, asthma, COPD, inflammatory bowel disease, psoriasis, atopic dermatitis, and allergic rhinitis.
Citations
[1] Bristol-Myers Squibb Company. (2005, May 19). AU2003244799 B2. IP Australia.
[2] World Intellectual Property Organization. (2004). WO2004/056809 A1.
[3] United States Patent and Trademark Office. (2002). US Application No. 10/279,722.
