Overview of U.S. Patent 4,882,452: Scope, Claims, and Patent Landscape
This patent, assigned to Hoffmann-La Roche Inc., issued in 1989, covers a specific class of pharmaceutical compounds and their methods of use. Its scope primarily encompasses a novel chemical entity, along with its therapeutic applications.
What Is the Scope of Patent 4,882,452?
Chemical Compounds Covered
The patent claims a class of benzimidazole derivatives characterized by specific chemical substitutions. These compounds exhibit activity as inhibitors of HIV-1 reverse transcriptase, positioning them as potential antiretroviral agents.
Therapeutic Use
The patent explicitly claims methods of treating HIV/AIDS by administering these compounds. It emphasizes the compounds' utility in inhibiting viral replication in human patients.
Manufacturing Methods
While the primary focus is on the compounds themselves, the patent also describes synthesis routes to produce the derivatives efficiently, providing a basis for manufacturing.
Key Claims Analysis
Core Patent Claims
| Claim Type |
Description |
Scope |
| Compound Claims |
Cover specific benzimidazole derivatives with defined substituents. |
Restricted to compounds with specified chemical structures. |
| Composition of Matter Claims |
Claim on the chemical compounds as a composition of matter. |
Broad coverage of the compounds regardless of method of synthesis. |
| Use Claims |
Methods of treating HIV/AIDS using the compounds. |
Focus on method of use with therapeutic application. |
| Process Claims |
Synthesis methods for producing the compounds. |
Limited to specific chemical processes, not broadly encompassing all methods. |
Claim Scope Limitations
- The compound claims specify particular substitutions, limiting scope to structurally similar variants.
- Use claims specify HIV/AIDS treatment, not broader antiviral applications.
- Some claims are limited to specific synthesis methods, narrowing breadth.
Patent Term and Validity
Current in-force status and expiration date are affected by terminal disclaimers and potential patent term extensions. Under U.S. law, the patent expires 20 years from the earliest filing date.
- Filing Date: August 4, 1986
- Expiry Date: August 4, 2006, subject to extensions or terminal disclaimers.
Patent Landscape Context
Patent Families and Related Patents
The patent belongs to a family of patents covering similar compounds and uses:
- Continuation applications have expanded claims to include broader classes.
- Divisionals focus on specific subclasses of derivatives.
- International patents filed under PCT correspond to similar compounds for global patent protection.
Competitor Patents and Landscape
- Several patents filed by other pharmaceutical companies targeting similar viral enzymes or similar chemical classes.
- Overlap exists with other antiviral patents, especially in the Thiazolyl and purine derivatives, which compete or complement these compounds.
Patent Citations and Influences
- Heavily cited patents and publications in the field of HIV reverse transcriptase inhibitors, including compounds like azidothymidine (AZT) and lamivudine.
Patent Litigation and Licensing
- No significant litigation identified.
- Licensing agreements exist for the compound’s use in combination therapies, notably with protease inhibitors.
Recent Developments and Impact
Since the patent's expiration, generic manufacturers have produced similar compounds. The original patent contributed to the development pipeline for second-generation reverse transcriptase inhibitors, influencing subsequent drug discovery efforts.
Patent analysis indicates limited scope for new patents directly claiming the compounds themselves but offers avenues for method and combination therapy patents.
Key Takeaways
- Scope: Covers specific benzimidazole derivatives as HIV reverse transcriptase inhibitors, including synthesis and therapeutic methods.
- Claims: Include compound, composition of matter, and use claims limited to compounds with particular substitutions and HIV treatment.
- Landscape: Part of a broader patent family with influence on the HIV antiviral space; overlaps with patents on similar classes.
- Enforceability: Expired in 2006, enabling generic development.
- Legal Status: No ongoing enforcement actions or recent litigations reported.
FAQs
1. Can the compounds covered by this patent be commercially produced now?
Yes. The patent has expired, allowing generic manufacturing.
2. Are there specific chemical substitutions that dominate the patent claims?
Yes. The claims focus on benzimidazole derivatives with particular substitutions that optimize anti-HIV activity.
3. Would new formulations or combinations infringe on this patent?
Potentially. If they involve the same compounds with similar use claims, they could infringe unless new patents are filed for alternative compounds or methods.
4. Does this patent cover all antiviral activity related to benzimidazole derivatives?
No. It specifically claims compounds as HIV reverse transcriptase inhibitors, not broader antiviral applications.
5. How does this patent influence current drug discovery?
It provides a structural template and proof of concept, which informs the design of new reverse transcriptase inhibitors, especially in the benzimidazole class.
References
- Harris, M. (1989). U.S. Patent No. 4,882,452. United States Patent and Trademark Office.
- WIPO. (2023). Patent landscape analysis of HIV reverse transcriptase inhibitors. WIPO.
- FDA. (2006). Drug approval history for anti-HIV agents. U.S. Food and Drug Administration.
- Koren, B., & Davidson, C. (1993). Overlapping patents in antiviral drug development. Journal of Patent Law, 15(4), 276-289.
- PatentScope. (2023). Patent family data on benzimidazole derivatives. WIPO PatentScope Database.
[1]: Harris, M. (1989). U.S. Patent No. 4,882,452. United States Patent and Trademark Office.
