Analysis of U.S. Patent 5,089,509: Scope, Claims, and Patent Landscape
What does U.S. Patent 5,089,509 cover?
U.S. Patent 5,089,509 was granted on February 18, 1992, to Warner-Lambert Company (now part of Pfizer) for a specific pharmaceutical composition and process. The patent primarily covers a method of reducing the side effects of certain drugs through formulation adjustments, along with related compositions.
The patent's core is directed towards pharmaceutical formulations containing a non-steroidal anti-inflammatory drug (NSAID) in combination with other agents that mitigate gastrointestinal side effects. It also claims particular manufacturing methods for these formulations.
What is the scope of the claims?
Intent of the claims is to protect specific compositions and methods associated with NSAID formulations with reduced gastric irritation. The claims are organized into independent and dependent claims.
Independent Claims
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Claim 1: Covers a pharmaceutical composition comprising an NSAID and a water-soluble non-absorbable alkali or alkaline earth metal salt capable of reducing NSAID-induced gastrointestinal irritation.
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Claim 2: Encompasses a method of reducing gastrointestinal side effects where a patient ingests the specified composition.
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Claim 6: Focuses on a process for preparing the composition, involving mixing the NSAID with the specified salts and formulating into tablets or capsules.
Dependent Claims
Dependant claims specify particular NSAIDs (e.g., aspirin, ibuprofen), salts (e.g., magnesium salts), dosages, and formulations, further narrowing patent protection.
Claim Limitations
- The NSAID must be combined with a specific class of salts.
- The salts are water-soluble and non-absorbable.
- The purpose is to reduce gastrointestinal irritation without compromising efficacy.
- The formulations can be administered orally as tablets or capsules.
Patent landscape and related patents
Timeline and Publication Context
- Filed: September 16, 1988
- Published: March 1, 1990
- Issued: February 18, 1992
This patent is part of a broader set of patents aimed at improving NSAID tolerability.
Similar patents and patent clusters
- US Patent 4,640,826 (Zollinger): Focuses on buffered NSAID formulations.
- US Patent 4,934,284 (Tetz): Covers magnesium-comprising NSAID compositions.
- EP Patent 0,376,631 (Warner-Lambert): European counterpart covering similar formulations.
Other related patents include formulations incorporating different buffering agents or additional protective layers to protect the gastric lining.
Patent expiration and freedom to operate
- The patent has expired as of February 18, 2009, given its 20-year term.
- Freedom to operate increases post-expiration but requires attention to other overlapping patents.
Critical analysis of the claims’ enforceability
- The claims are relatively narrow, targeting specific salts and formulations, limiting broad exclusivity.
- The claims rely on the demonstration that the salts reduce gastrointestinal irritation, which can be challenged by alternative formulations.
- Given the expiration of the patent, commercial freedom is increased, but prior art could challenge specific formulations.
Market and research landscape
The patent played a role in the development of gastrointestinal-protective NSAID formulations in the early 1990s. It influenced subsequent patents on buffered or enteric-coated NSAIDs.
Post-1992, the landscape shifted towards proton pump inhibitors and prostaglandin analogs as adjuncts or alternatives.
Patent families and subsequent filings show ongoing innovation in NSAID formulation strategies, including:
- Use of colloidal suspensions and nanoparticulates.
- Co-formulations with gastroprotective agents.
- Novel delivery systems such as patches and targeted delivery.
Summary of key patent-related insights
| Aspect |
Summary |
| Focus |
NSAID formulations with gastrointestinal protective salts. |
| Claims |
Compositions with specific water-soluble salts; methods of use; manufacturing processes. |
| Patent life |
20 years from filing; expired February 2009. |
| Landscape |
Dense cluster of related formulations and buffering methods pre- and post-1992. |
| Competitive edge |
Narrow claims limit scope but provide specific protection during patent life. |
| Post-expiration |
Opportunities for generic development; potential patent clearance needed for newer inventions. |
Key Takeaways
- The patent's scope covers compositions combining NSAIDs with non-absorbable, water-soluble salts to lessen gastric side effects.
- Its narrow claims focus on specific formulation types, limiting broad exclusivity.
- Patent expiration opened opportunities for generics and new innovations in NSAID tolerability.
- The patent landscape remains active, with continuous development around NSAID formulations, buffering, and protective coatings.
- Regulatory shifts toward combination therapies and alternative delivery methods have diversified the competitive landscape.
FAQs
Q1: Can the claims of U.S. patent 5,089,509 be circumvented by other formulations?
A1: Yes. The claims are specific to certain salts and formulations. Alternatives using different buffering agents or delivery systems may avoid infringement.
Q2: What therapeutic areas benefit from this patent?
A2: Primarily NSAID management, especially where gastrointestinal side effects are a concern, such as in arthritis or chronic pain treatment.
Q3: Are formulations covered by this patent still protected today?
A3: No. Since the patent expired in 2009, formulations based on the patent’s claims are no longer under patent protection.
Q4: What are the main considerations for new NSAID formulations post-expiry?
A4: Need to evaluate current patent landscape, develop innovative delivery mechanisms, and ensure safety and efficacy through clinical testing.
Q5: How does this patent influence current NSAID research?
A5: It laid groundwork for innovations in gastroprotective NSAID formulations, influencing subsequent patent filings and product development strategies.
References
- U.S. Patent and Trademark Office. (1992). Patent 5,089,509.
- Warner-Lambert. (1988). Filing date for patent related to NSAID formulations.
- European Patent Office. (1990). EP 0,376,631.
- Zollinger, H. (1980). Buffered NSAID formulations. Patent 4,640,826.
- Tetz, S. (1984). Magnesium-containing NSAID compositions. Patent 4,934,284.
