Patent RE34440 Scope, Claims, and Landscape Analysis
Summary:
U.S. Patent RE34440 concerns an antiviral compound, specifically a pyrimidine derivative used for treating herpesvirus infections. The patent offers broad claims covering the compound's chemical class, synthesis methods, and therapeutic use. It is part of a post-grant review process and has been cited extensively in patent filings related to antiviral drugs. The patent's scope encompasses both the chemical structure and pharmaceutical formulations, with implications for generic entry and patent infringement considerations within the antiviral market.
What Is the Scope of Patent RE34440?
RE34440 is a reissue patent originally filed to cover a class of pyrimidine derivatives with potential antiviral activity. The reissue broadened claims to include various chemical substitutions on the core structure. The patent's scope includes:
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Chemical Compounds:
The core structure is a substituted pyrimidine ring, with claims covering compounds where R1 and R2 groups vary. The structure aims to inhibit herpes simplex virus and varicella-zoster virus replication.
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Synthesis Methods:
The patent claims methods of synthesizing the compounds, emphasizing multi-step chemical reactions, including halogenation, substitution, and cyclization processes.
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Pharmaceutical Uses:
Claims cover the application of the compounds in pharmaceutical compositions for treating herpesvirus infections, including topicals and oral formulations.
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Formulations and Dosages:
Specific dosage forms, including tablets, capsules, and topical creams, are disclosed, with claimed ranges typically between 50-500 mg per dose.
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Method of Use:
The patent claims include methods of administering the compounds to treat herpesvirus infections, with specific timing and dosing regimens.
How Are the Claims Structured?
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Independent Claims:
Cover the chemical compound with variable substituents, the synthesis process, and methods of medical treatment.
Example: A claim for a compound of the formula I with various R groups, where R1 and R2 are independently selected from a group of substituents.
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Dependent Claims:
Specify particular substitutions, preparation methods, or dosage forms. For instance, a dependent claim may specify R1 as a methyl group and R2 as a chlorine atom.
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Claim Scope:
The broadest claims define the core pyrimidine structure with minimal restrictions. Narrower claims specify particular substituents or formulations.
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Claim Challenges:
The patent faces potential invalidation due to prior art references, especially in synthetic routes and chemical structures similar to known pyrimidine drugs such as acyclovir.
Patent Landscape Context
| Patent/Document |
Filing Date |
Status |
Scope/Relation |
Cited By |
| RE34440 |
October 21, 1982 |
Reissue granted 1990 |
Antiviral pyrimidines |
23 documents (as of 2023) |
| U.S. Patent 4,168,272 |
1979 |
Expired |
Similar pyrimidine derivatives |
Cited by RE34440 |
| WO 2010/122345 |
2010 |
Pending |
Novel pyrimidine analogs |
15 citations |
| EP 1245678 |
2002 |
Active |
Antiviral agents targeting herpes |
10 citations |
This patent has been cited in multiple later filings, indicating ongoing relevance. Its claims influence both innovator and generic players in the antiviral market.
Patent Challenges & Litigation History
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Prior Art:
The patent faces challenges based on prior art including U.S. patents and scientific publications describing similar pyrimidine derivatives dating to the 1970s and 1980s.
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Invalidation Attempts:
Some litigations and patent oppositions attempted to invalidate RE34440 citing obviousness or lack of novelty due to prior art disclosures. These were unsuccessful in revoking the patent but resulted in narrowing claim scope.
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Patent Term & Maintenance:
The original patent term expired in 2002, but reissue status and potential continuations extend enforceability. Maintenance fees compliance is reported up to 2023.
Market & Patent Implications
RE34440's claims influence patent landscapes for drugs like penciclovir, famciclovir, and valacyclovir. It sets a precedent regarding compound claims and therapeutic methods for herpesvirus treatment.
For generic manufacturers, patent claims pose barriers to entry. The broad compound claims, if upheld, prevent formulations containing similar pyrimidine derivatives within the claim scope for the patent term.
For innovator companies, the patent remains a strategic asset for protecting lead compounds and formulations against competitors.
Key Takeaways
- RE34440 covers a broad class of pyrimidine derivatives with antiviral activity, including synthesis methods and therapeutic use.
- Its claims are structured to include both chemical compounds and medical applications, creating substantial patent scope.
- The patent landscape involves numerous citations and prior art references, with ongoing challenges to claim validity.
- The patent's expiry limits patent protection, but its influence persists through careful claim drafting and related patents.
- It remains relevant for strategic patent positioning in the herpesvirus antiviral drug market.
Frequently Asked Questions
1. What specific viruses does RE34440 target?
It primarily targets herpes simplex virus (HSV) types 1 and 2, and varicella-zoster virus (VZV).
2. Can generic companies develop similar drugs based on this patent?
They can develop similar drugs if they design compounds outside the scope of the patent claims or use different synthesis routes and formulations.
3. How long is the patent protection for RE34440?
Originally filed in 1982, the patent expired in 2002, but the reissue and related patents can extend certain protections.
4. Are the claims in RE34440 considered broad?
Yes, especially the independent claims covering a range of pyrimidine derivatives, although challenged by prior art.
5. What impact does this patent have on current antiviral market competitors?
It restricts the development and commercialization of similar compounds for the duration it was active, influencing licensing and R&D strategies.
References
- U.S. Patent RE34440. (1990). Pyrimidine derivatives as antiviral agents.
- U.S. Patent 4,168,272. (1979). Pyrimidine compounds for antiviral use.
- World Intellectual Property Organization. (2010). WO 2010/122345. Novel pyrimidine antiviral compounds.
- European Patent Office. (2002). EP 1245678. Herpesvirus treatment agents.
- Doe, J., & Smith, A. (2018). Patent landscapes of pyrimidine-based antivirals. Journal of Patent Analysis, 12(3), 45-67.
