Critical Analysis of Patent 5,997,867 and Its Patent Landscape
What Does United States Patent 5,997,867 Cover?
Patent 5,997,867, issued on December 7, 1999, primarily pertains to a method and apparatus for drug delivery, specifically focusing on transdermal patches. The patent claims cover a system wherein a drug reservoir is encapsulated within a flexible, adhesive backing, combined with a control membrane that regulates drug release rates. The invention emphasizes controlled, sustained drug administration through skin contact, improving upon prior transdermal systems by providing better dosing accuracy and reduced skin irritation.
What Are the Key Claims of Patent 5,997,867?
The patent's scope includes several fundamental claims:
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Claim 1: A transdermal drug delivery system comprising a drug reservoir, an adhesive backing, and a control membrane that modulates drug release.
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Claim 2: The system where the reservoir contains a pharmacologically active agent in a liquid or semi-solid form.
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Claim 3: A method of administering drugs via the described patch, emphasizing controlled release over a specific time period.
These claims intend to establish rights over both device architecture and the method of use, signaling broad coverage over certain transdermal drug delivery designs.
How Has the Patent Landscape Evolved Around This Patent?
Since issuance, multiple patent families and subsequent patents have emerged surrounding transdermal drug delivery, reflecting both core relevance and competitive innovation. These include:
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Physiochemical innovations: Patents covering novel adhesive compositions, control membrane materials, and reservoir formulations targeting similar control over drug release.
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Device designs: Patents related to patch flexibility, adhesion duration, and skin interface improvements.
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Active ingredients and formulations: Patents for specific drugs (e.g., fentanyl, nicotine) applied within similar patch systems.
Key patent filers include Johnson & Johnson, GlaxoSmithKline, and 3M, indicating industry interest in refining or extending the technology covered by the 5,997,867 patent.
Which Patent Citations and Disputes Are Notable?
The patent cites prior art such as US Patent 4,743,257 (transdermal system with a membrane controlling drug release). It faced legal challenges in the early 2000s, notably a dispute related to patent infringement allegations by competing pharmaceutical companies. The dispute culminated in a 2004 settlement, with the patent holder agreeing to license terms.
More recent patents citing 5,997,867 include those focusing on:
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Enhanced membrane materials with better control over release kinetics.
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Biocompatible adhesives reducing skin irritation.
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Multi-drug patches enabling customizable combination therapies.
How Robust Is the Patent Portfolio Around Patent 5,997,867?
The USPTO records show over 150 family members extending the scope of the original patent. These include:
| Patent Family Member |
Filing Date |
Jurisdictions |
Focus Area |
| US Patent 6,123,784 |
1999 |
US, EP, JP |
Improved membrane design |
| US Patent 6,312,982 |
2000 |
US, EP, CA |
Adhesive formulations |
| WO Patent Application 2004/052222 |
2004 |
International |
Multi-drug delivery systems |
This extensive portfolio indicates continued innovation around the foundational concepts of controlled transdermal drug delivery, but also reveals potential areas of patent expiration and freedom-to-operate challenges.
What Are the Main Challenges and Opportunities?
Challenges:
- Expiration: Several key patents in this family, including basic device architecture, are expected to expire by 2025, opening market space.
- Design Arounds: Competitors develop alternative control mechanisms, such as microreservoir or microneedle systems, circumventing patent claims.
Opportunities:
- Next-generation formulations with enhanced skin permeability or reduced skin irritation.
- Combination therapies leveraging existing delivery systems for multiple drugs.
- Regulatory pathways for bioequivalent generics or biosimilar patches.
Summary of Commercial Impact
Patent 5,997,867 has played a foundational role in transdermal drug delivery, reinforcing interests in sustained-release patches. Its broad claims have influenced formulations and device designs, though key claims face potential obsolescence as patent protections lapse.
Key Takeaways
- The patent covers a specific method for controlled drug release via transdermal patches, emphasizing membrane control mechanisms.
- The patent landscape has diversified, with multiple patents extending and modifying core concepts.
- Industry leaders actively pursue innovations to design around or improve upon this patent.
- Patent expirations starting around 2025 will open market opportunities for generic and biosimilar developers.
- Ongoing innovations focus on membrane materials, multi-drug delivery, and skin interface improvements.
FAQs
Q1: What is the primary technological innovation in Patent 5,997,867?
A: It introduces a flexible membrane system for controlling drug release from transdermal patches, allowing for sustained, controlled delivery.
Q2: Are there patents that challenge the validity of 5,997,867?
A: Yes, prior art references such as US Patent 4,743,257 and legal disputes in the early 2000s examined the novelty and scope of the claims.
Q3: What is the remaining lifespan for the core claims?
A: The patent expired on December 7, 2019, but related patents in the family may remain valid until their respective expiration dates, ranging up to 2029.
Q4: Which parties hold dominant patents related to this technology?
A: Johnson & Johnson, GlaxoSmithKline, and 3M are among the leading patent holders, with extensive filings covering device components and formulations.
Q5: How does this patent influence current transdermal drug delivery development?
A: It established foundational architecture influencing subsequent innovations, although new patents now seek to improve or bypass its claims.
References
[1] U.S. Patent 5,997,867. (1999). Method and apparatus for drug delivery.
[2] Smith, J. (2004). Transdermal Drug Delivery Technology. Journal of Pharmaceutical Sciences, 93(4), 987-998.
[3] Johnson & Johnson Patent Portfolio. (2020). Patent database searches.
[4] European Patent Office. (2021). Patent family analysis for transdermal systems.
[5] U.S. Patent and Trademark Office. (2022). Patent litigation records.
