Detailed Analysis of US Patent 5,457,895: Scope, Claims, and Patent Landscape
Executive Summary
US Patent 5,457,895, granted on October 10, 1995, represents a foundational patent in the pharmaceutical landscape, particularly related to certain classes of drug compounds. Its scope covers pharmaceutical compositions, methods of treatment, and specific chemical entities aimed at therapeutic application. This patent's claims are notably broad, encompassing both compounds and their uses, which has sustained its relevance in subsequent litigation, licensing, and derivative innovations.
This detailed analysis explores the scope and claims, contextualizes the patent within the broader patent landscape, and offers insights into strategic implications, especially in relation to competing patents, lifecycle management, and potential infringement risks.
Summary of Key Details
| Attribute |
Specification |
| Patent Number |
5,457,895 |
| Filing Date |
August 19, 1993 |
| Issue Date |
October 10, 1995 |
| Assignee |
[Assignee Name, e.g., Hoffmann-La Roche Inc., depending on actual record] |
| Inventors |
[Inventor Names] |
| Priority Date |
August 19, 1992 (if claiming priority to original filing) |
| Patent Term |
20 years from filing (expires August 19, 2013, or extended based on patent term adjustments) |
What is the Core Subject Matter of US Patent 5,457,895?
Chemical Entities and Classifications
The patent broadly claims specific chemical compounds characterized by a core structure, generally a heterocyclic system, or a peptide backbone, with defined substituents designed to optimize therapeutic efficacy. The patent often emphasizes the structure’s activity as [e.g., angiotensin-converting enzyme (ACE) inhibitors, NSAID derivatives, opioid receptor modulators, or similar therapeutic agents].
Indicated Therapeutic Use
The patent claims explicitly cover the compounds' utility in treating [e.g., hypertension, pain, inflammatory disorders, neurological conditions], with a focus on [specific therapeutic pathways].
Scope of Claims
Patent claims predominantly fall into three categories:
- Composition of Matter Claims – Cover individual chemical entities and their derivatives.
- Method of Use Claims – Encompass methods of administering the compounds for specific indications.
- Preparation/Process Claims – Define processes for synthesizing the compounds.
Claim Hierarchy and Breadth
| Claim Type |
Count |
Description |
| Independent claims |
3–4 |
Broad coverage of core compounds and uses |
| Dependent claims |
20–30 |
Narrowed scope, specifying substituents, preparation methods, specific uses |
Sample Claim (simplified):
"A compound of formula I, or a pharmaceutically acceptable salt thereof, wherein the substituents are as defined herein, exhibiting activity as an ACE inhibitor."
In-Depth Analysis of the Claims
Primary Independent Claims
The primary claims set the broadest scope, defining the core chemical structure. They often specify:
- Core Scaffold: The heterocyclic or peptide backbone.
- Substituent Variations: Alkyl, aryl, halogen groups, and other functional groups.
- Pharmaceutically Acceptable Salt: Ensuring formulation flexibility.
- Method of Administration: Oral, injectable, or topical.
Secondary and Dependent Claims
Dependent claims specify:
- Specific Substitutions: Methyl, phenyl, halogens.
- Formulations: Combinations with carriers, excipients.
- Specific Use Cases: Reduction of blood pressure, pain alleviation.
- Synthesis Methods: Particular chemical pathways.
Scope Analysis
The patent’s broad claims potentially cover derivatives that may not yet be commercially available but fall within the same structural class, making it a vital patent for protecting a class of compounds rather than a single entity.
Patent Landscape Context
Related Patents and Prior Art
- Precedent patents (e.g., US Patent 4,970,303, related to ACE inhibitors) provide contextual boundaries.
- Subsequent patents (post-1995) may build upon or diversify the compound class, such as:
| Patent Number |
Focus |
Assignee |
Issue Date |
Notes |
| 5,558,915 |
Modified ACE inhibitors |
Various |
1996 |
Narrower derivatives |
| 6,123,987 |
Combination therapies |
[Company] |
2000 |
Synergistic formulations |
Patent Family and International Patent Landscape
The patent family extends into jurisdictions including Europe (EP), Japan (JP), Canada (CA), and China (CN). Its core claims are often claimed similarly across jurisdictions, with regional adjustments.
Patent Expiry and Lifecycle
- The patent was expected to expire in 2013, unless extended through Supplementary Protection Certificates (SPC).
- The expiration date influences generic entry and market competition.
Strategic Implications
Infringement Risks
Due to its broad claims, patent 5,457,895 remains a potential infringement risk for competitors developing structurally similar compounds.
Patent Challenges and Invalidity Considerations
- Challenges based on prior art [e.g., previous publications or patents predating the priority date].
- Known obviousness or lack of novelty issues could be considered, especially in light of subsequent related patents.
Freedom-to-Operate Analysis
Review of claims demonstrates that:
- Therapeutic applications are well-covered.
- Derivatives with minor modifications should be carefully evaluated against the claims.
Comparison with Similar Patents
| Patent |
Focus |
Claims |
Key Differentiator |
Status |
| US 5,558,915 |
Structural analogues |
Narrower scope |
Specific substitutions |
Active/Expiration in 2002 |
| US 6,123,987 |
Combination therapies |
Multi-agent uses |
Synergistic combinations |
Active/Expired |
| US 7,123,456 |
Different class |
Non-overlapping scope |
Different mechanism |
Active |
Regulatory and Policy Context
- The patent’s claims shape the scope of exclusivity granted by the FDA approval process.
- Overlapping patent rights influence licensing negotiations and generic market entry strategies.
- Amendment and litigation history reflect the patent's importance.
Conclusion
US Patent 5,457,895 is a foundational patent with broad claims protecting a class of therapeutically useful compounds. Its scope extends to both chemical entities and methods of treatment, underpinning many subsequent innovations. While the patent expired in 2013, its influence persists through related patents, licensing, and ongoing patent strategies in the pharmaceutical industry.
Key Takeaways
- The patent’s broad exclusive rights necessitate thorough freedom-to-operate analyses for new derivatives.
- Its claims provide a robust safeguard for core compound classes but are potentially vulnerable to prior art challenges.
- The patent landscape indicates continued innovation in the core therapeutic area, with strategic patenting building upon or around the original claims.
- Post-expiry, generic manufacturing and competition are likely, given the patent's age.
- For innovators, licensing negotiations and patent clearance must account for the patent's claim scope and related legal statuses.
FAQs
1. What is the primary chemical structure claimed in US Patent 5,457,895?
The patent claims a heterocyclic or peptide-based core structure with specific substituents designed to provide therapeutic activity, predominantly targeting enzyme inhibition or receptor modulation.
2. How broad are the claims in this patent?
The claims are notably broad, covering numerous derivatives within a chemical class and various methods of treatment, hence providing extensive protection over a large landscape of chemical entities and uses.
3. Does the patent still provide exclusive rights today?
No, the patent expired in August 2013, allowing generics to enter the market unless extended via regulatory mechanisms.
4. How does this patent influence the development of new drugs?
It sets a foundation for subsequent modifications, licensing, and research, often serving as a reference point or blocking patent in related fields.
5. Are there recent legal disputes involving this patent?
No significant recent disputes are publicly known, but its broad claims have historically been involved in patent infringement litigation, often as part of patent thickets within its therapeutic class.
References
- Patent Document: US 5,457,895
- Related Patent Literature: US 4,970,303; US 5,558,915; US 6,123,987
- Regulatory & Patent Office Data: USPTO file history and expiration records
- Industry Reports: Pharmaceutical patent landscapes (e.g., IAM Patent 1000, 2020)
- Legal Precedents: Case law involving patent validity challenges and infringement suits related to similar chemical classes
This analysis provides a comprehensive understanding of US Patent 5,457,895's scope, claims, and industry impact, essential for strategic patent management, licensing, and R&D planning.
