Scope, Claims, and Patent Landscape Analysis of U.S. Patent 5,114,948
Summary
U.S. Patent 5,114,948, granted to Glaxo Inc. on May 19, 1992, pertains to a synthetic corticosteroid derivative, specifically a method for making 21-acetyloxy-16,17-dihydro-3α,21-dihydroxy-6-methylpregna-1,4-diene-11,20-dione. The patent's claims cover the synthesis process and the compound itself, intended for use in anti-inflammatory applications. Over time, the patent's intellectual property has influenced subsequent developments in corticosteroid derivatives and formulations.
What is the Scope of U.S. Patent 5,114,948?
The patent claims two primary aspects:
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Chemical Compound: The patent claims the corticosteroid derivative 21-acetyloxy-16,17-dihydro-3α,21-dihydroxy-6-methylpregna-1,4-diene-11,20-dione, along with its pharmaceutically acceptable salts.
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Synthesis Method: It discloses a specific process for synthesizing the compound, involving acetylation, reduction, and other chemical steps to produce the desired steroid derivative.
The scope encompasses:
- The specific chemical structure as a novel compound.
- The process steps to produce this compound.
- Pharmaceutical formulations comprising the compound.
The claims do not specify particular therapeutic methods but imply utility in anti-inflammatory or corticosteroid-related applications.
What Are the Key Claims?
The patent contains 12 claims, with the following being core:
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Claim 1: A compound selected from the group consisting of 21-acetyloxy-16,17-dihydro-3α,21-dihydroxy-6-methylpregna-1,4-diene-11,20-dione and its pharmaceutically acceptable salts.
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Claim 2: The method of preparing the compound involving steps of acetylation followed by reduction to afford the specified 21-acetyloxy derivative.
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Claims 3-12: Dependent claims that specify particular synthesis conditions, solvents, reagents, and intermediate compounds.
In essence, the patent claims protect both the chemical entity and its synthesis process.
Patent Landscape & Related Patents
Historical Context & Family:
This patent was filed by Glaxo Inc. in 1989, issued in 1992. It sits within a broader patent family related to corticosterone derivatives, aiming to improve anti-inflammatory potency and reduce side effects.
Subsequent Patents & Derivative Drugs:
- Patents around this time and afterwards sought to cover various modifications of corticosteroids, including fluticasone and mometasone.
- Several later patents claim formulation-specific combinations, delivery methods, or synergistic uses of corticosteroids.
- Patent expirations in 2009-2010 have opened pathways for generic versions.
Legal Status & Litigation:
- The patent remained active until June 11, 2009, marking its expiration date, after which generic manufacturers could legally produce similar compounds.
- No major litigation has been publicly associated with this patent post-expiration.
Patent Office Bibliography & Cited Art:
- The patent cites prior art related to corticosteroids, including U.S. patents such as 3,344,126 and 3,947,632, which cover earlier steroid modifications.
- It is cited by subsequent patents aiming to develop corticosteroid derivatives with improved pharmacokinetics.
Impact & Limitations
Innovative Aspects:
- The specific chemical modification (acetoxy at position 21) aimed at increasing potency and reducing systemic side effects.
- Synthetic methodology with improved yields and process control.
Limitations:
- The patent’s claims do not cover other corticosteroid derivatives, limiting scope to the specific compound.
- The expiration of the patent broadened the competitive landscape, enabling generics.
Conclusion
U.S. Patent 5,114,948 claims a specific corticosteroid derivative and its synthesis. Its scope covers chemical structure and manufacturing processes, influencing subsequent corticosteroid patents and formulations. Its expiration facilitated generics entering the market, reducing barriers to competition.
Key Takeaways
- The patent centers on a chemically defined corticosteroid with anti-inflammatory potential.
- Claims cover both the compound and its synthesis process.
- It is part of a broader corticosteroid patent landscape, with subsequent developments extending or circumventing its claims.
- The patent expired in 2009, paving the way for generic formulations.
- Its impact persists in the chemical structure and process innovations within corticosteroid drugs.
FAQs
1. Does this patent cover specific therapeutic uses?
No. It claims the compound and synthesis method, not specific medical indications or treatment methods.
2. Are similar compounds protected under this patent?
No. Structural analogs or derivatives differing significantly from the claimed compound are outside its scope unless claimed separately.
3. How does the patent landscape affect current drug development?
The patent's expiration reduces barriers, enabling new formulations or generics based on similar chemical structures.
4. Were there any notable litigations involving this patent?
No major litigations have been recorded post-expiration.
5. Is the synthesis process still relevant today?
The process described was innovative for its time but has largely been superseded by more efficient methods in current pharmaceutical manufacturing.
References
- U.S. Patent 5,114,948.
- Patent Family Information and legal status (USPTO).
- Literature on corticosteroid derivates, including prior art patents cited within the patent document.
- Market data and generic drug approval timelines (FDA Orange Book).
