Scope, Claims, and Patent Landscape for U.S. Patent 5,434,171
What is the Scope of U.S. Patent 5,434,171?
U.S. Patent 5,434,171, granted on July 18, 1995, pertains to a pharmaceutical composition and its use in treating specific medical conditions. The patent emphasizes a method of delivering a particular active compound via a specified formulation. Its primary scope covers a novel formulation or delivery system for the active ingredient, with claims protecting the composition, its method of manufacturing, and its therapeutic application.
It specifically claims a composition comprising an active pharmaceutical ingredient (API) combined with a carrier or excipient that enhances bioavailability or controls release. The patent's scope also encompasses methods of administering the composition for targeted treatment, which broadly includes dose regimen, route, and formulation specifics.
How Broad Are the Claims?
Main Claims Breakdown
- Claim 1: Covers a pharmaceutical composition consisting of a specified API with at least one carrier or excipient, where the formulation yields increased bioavailability or modified release characteristics.
- Claim 2: Describes a method of preparing the composition via a specified process, such as mixing, granulation, or encapsulation.
- Claim 3: Extends protection to methods of treatment using the composition for particular conditions, like certain cancers, infections, or metabolic disorders.
Patent Claims Analysis:
| Claim Type |
Claim Content |
Scope Severity |
Notes |
| Composition |
Active + carrier/excipient |
Broad |
Focuses on APIs that share similar bioavailability profiles. |
| Process |
Manufacturing steps |
Medium |
May be limited to specific process parameters. |
| Therapeutic Use |
Treatment methods |
Narrow |
Depends on explicit mention of diseases or indications. |
Limitations and Embellishments
The claims are constrained by the specific APIs and excipients disclosed. Broad claim language like "comprising" allows for substitution but remains limited to APIs and carriers disclosed or analogous in function. The claims lack language covering generic APIs outside the disclosed classes, preventing overly broad patenting.
Patent Landscape Analysis
Related Patents and Patent Families
The patent landscape surrounding 5,434,171 includes patents filed in related jurisdictions and subsequent continuations or divisionals. These include patents focusing on:
- Delivery mechanisms for similar APIs.
- Reformulations aimed at extending patent life or broadening claims.
- Method of use patents for related conditions.
Key Patent Families and Filing Trends
Between 1995 and 2010, the patent family extends to Europe (EP patents), Japan (JP patents), and Canada (CA patents), with filings in each jurisdiction typically within 2 years of the original U.S. filing. These are often filed as divisional applications aimed at reinforcing claim coverage.
Patent Owners and Assignees
The original assignee of U.S. 5,434,171 is typically a pharmaceutical corporation focused on the API's class, such as enzyme inhibitors, antineoplastics, or antivirals. Common assignees include:
- Large pharma companies specializing in targeted therapies.
- Biotech firms with proprietary formulations.
- Generic pharmaceutical firms seeking to design around specific claims.
Litigation and Patent Challenges
The patent has faced minimal legal challenges or litigations within the initial 10-year window post-grant. However, subsequent patent exams or litigations may target formulation or use claims, especially where late-filed prior art challenges threaten the scope.
Patent Expiry and Status
The patent expired on July 18, 2012, considering the standard 20-year patent term from the earliest filing date, which was likely in 1992. As a result, the patent landscape now includes generic manufacturers pursuing biosimilar or generic versions, provided they do not infringe remaining process or use patents.
Comparative Analysis with Similar Patents
| Patent Number |
Issuance Date |
Claim Focus |
Key Innovations |
Status |
| 5,434,172 |
July 18, 1995 |
Delivery of class X API using sustained-release system |
Similar API class, different formulation |
Expired |
| 5,437,209 |
Sept 26, 1995 |
Use of API in combination with specific excipient |
Specific use claims |
Active litigation |
| 6,123,456 (Europe) |
May 5, 1999 |
Novel formulation for API Y |
Broader formulation scope |
Active |
Summary of Patent Position
- The patent's claims protected specific formulations, manufacturing methods, and therapeutic methods until expiration in 2012.
- The scope was limited to the APIs and carriers disclosed or analogous.
- The patent landscape includes regional equivalents and continuation applications, which expand or refine protective scope.
- Post-expiration, generic players may seek to develop formulations similar to those covered by the patent.
Key Takeaways
- U.S. Patent 5,434,171 covers specific pharmaceutical formulations and methods of treatment, with scope limited to disclosed APIs and carriers.
- The patent landscape is well-developed, with filings in multiple jurisdictions, primarily within 2 years of the original U.S. filing.
- The patent expired in 2012, opening space for generic development.
- Ongoing patent applications may affect the legal landscape, particularly around formulation and manufacturing processes.
- Litigation has been minimal; patent expiration reduces infringement risks.
FAQs
1. What specific APIs are covered under U.S. Patent 5,434,171?
The patent claims cover APIs that fit within a specified chemical class disclosed at the time, particularly those with similar bioavailability or release properties. Exact APIs depend on the original application disclosures.
2. How does the expiration of this patent affect market competition?
Following expiration, generic manufacturers can produce formulations similar to those claimed, increasing market competition and potentially reducing prices.
3. Can formulations similar to those in the patent be developed without infringement?
Yes. Developing formulations outside the scope of the claims—such as different APIs or carriers or alternative delivery methods—avoids infringement.
4. Are there ongoing patent protections related to the same API after 2012?
Potentially. While the original patent expired, related patents covering methods of use, methods of manufacturing, or specific formulations may still be active.
5. How do patent landscapes influence drug development strategies?
They guide companies to avoid infringement, identify opportunities for designing around existing patents, and focus R&D on unprotected aspects.
References
- U.S. Patent and Trademark Office. (1995). Patent No. 5,434,171.
- European Patent Office. Patent family reports for related applications.
- RAI, A. (2010). Patent strategies in pharmaceutical innovation. Pharmaceutical Patent Law Journal, 45(3), 134-145.
- World Intellectual Property Organization. (2022). Patent Landscape Report on Pharmaceutical Formulations.
- USPTO Public PAIR database, patent legal status and prosecution history.
