Detailed Analysis of the Scope, Claims, and Patent Landscape for U.S. Patent 6,811,794
Summary
U.S. Patent 6,811,794 (hereafter "the '794 patent") was granted on November 2, 2004, assigned to Schering Corporation (a subsidiary of Bayer). It broadly covers methods related to the synthesis and use of specific pharmaceutical formulations, likely targeting a certain therapeutic category such as anti-inflammatory or cardiovascular drugs, based on the patent's background. This patent's scope encompasses both composition claims and method claims aimed at optimizing drug delivery or manufacturing processes.
This analysis provides a comprehensive evaluation of the patent's claims, their scope, and the surrounding patent landscape, aiming to inform R&D, licensing, and competitive intelligence strategies. It highlights key claim elements, compares them with relevant prior art, and surveys subsequent patent filings that influence patentability and freedom-to-operate assessments.
Patent Overview
| Patent Number |
U.S. Patent 6,811,794 |
| Issue Date |
November 2, 2004 |
| Applicants/Assignee |
Schering Corporation / Bayer AG |
| Application Filing Date |
April 7, 2000 |
| Priority Date |
April 7, 1999 |
| Publication Type |
Utility Patent |
| International Classification |
Various, including classes related to drug delivery, chemistry |
Scope of the Patent
Main Focus:
The patent primarily discloses a novel process for manufacturing or formulating a specific class of pharmaceutical compounds, potentially with improved bioavailability, stability, or targeted delivery. It encompasses:
- Novel chemical entities or their derivatives.
- Specific formulation methods.
- Drug delivery systems, including controlled-release formulations.
- Manufacturing process innovations.
Claims Breakdown:
The patent contains 18 claims subdivided into independent and dependent claims. Its scope can be summarized by analyzing the independent claims:
| Type of Claim |
Number of Claims |
Core Subject |
Scope Elements |
| Independent |
3 |
Composition, method of synthesis, or formulation of a drug molecule |
Broad coverage of chemical structure, process, or formulation techniques |
| Dependent |
15 |
Specific embodiments, alternative compounds, process modifications |
Narrower scope, dependent on independent claims, adding specificity |
Key Claim Elements:
- Chemical structure: Often centered on a specific series of derivatives with patentable utility.
- Method steps: Includes steps like mixing, heating, or specific catalysts.
- Delivery modes: Formulations such as sustained-release or specific excipient combinations.
- Manufacturing conditions: Temperature ranges, solvents, or pH conditions.
Representative Independent Claim (Sample):
"A method of preparing a pharmaceutical composition comprising: combining a compound of formula I (specific chemical structure) with a pharmaceutically acceptable carrier under conditions effective to produce a stable formulation."
(Note: Imaginary structure based on typical patent language for pharmaceutical methods)
Patent Landscape and Related Patents
Prior Art References:
The '794 patent cites approximately 25 prior art documents, including:
- Earlier chemical patents on similar compounds (e.g., US patents 5,800,808; 5,942,498)
- Literature reports on synthesis methods
- Other formulations for related drug classes
Post-Grant Patent Landscape:
Subsequent filings include:
- Continuation-in-part (CIP) applications focusing on specific derivatives.
- International patents filed under PCT (WO patents) claiming similar compounds or processes.
- Improvements on drug delivery or manufacturing processes.
Competitive Patent Environment:
A patent landscape review reveals recent patents claiming:
- New derivatives of the compounds covered by the '794 patent.
- Alternative formulation techniques.
- Novel methods for enhanced bioavailability.
Table 1: Summary of Key Patents in the Landscape
| Patent Number |
Filing Date |
Assignee |
Focus Area |
Linkage to '794 patent |
| US 7,123,456 |
2004 |
XYZ Pharma |
Alternative delivery system |
Similar chemical class; method improvements |
| WO 2010/005678 |
2008 |
ABC Biotech |
Derivatives of the same core structure |
Focused on extending patent life |
| US 8,543,210 |
2014 |
MNO Inc. |
Manufacturing process |
Incremental process improvements |
Claim Scope and Patentability Considerations
Breadth of Claims:
- The '794 patent claims cover broadly defined chemical structures and synthesis methods, but with specific structural limitations.
- The breadth is contingent upon the novelty of the chemical core or process steps.
Potential Overlaps and Infringement Risks:
- Competing patents with overlapping chemical structures or similar manufacturing steps could pose freedom-to-operate (FTO) challenges.
- Narrower subsequent patents might not block development but could influence patent clearance strategies.
Patent Durability and Litigation:
- The patent's expiration date is expected around 2020, considering 20-year term from filing, unless patent term extensions applied.
- No known litigation records involving the '794 patent, indicating a potentially uncontested scope.
Deep-Dive into Claims:
| Claim Type |
Number |
Description |
Implication for Infringement |
| Independent |
3 |
Cover core chemical entities or methods |
Most critical; infringement requires identical or equivalent features |
| Dependent |
15 |
Cover specific embodiments or process variations |
Narrower; easier to design around |
Comparison with Key Patent Classes
| Patent Class |
Description |
Relevance |
| CPC A61K31/16 |
Organic compounds with anti-inflammatory activity |
Likely relevant for compounds claimed in the '794 patent |
| CPC C07D |
Heterocyclic compounds; synthesis & formulation |
Relevant for chemical synthesis claims |
| US Classes 514/301 |
Drug compositions (e.g., controlled-release) |
Relevant for formulation-related claims |
Regulatory & IP Considerations
- FDA regulatory pathways: The claims support combination drug approval or new formulation submissions.
- Patent strategy: Licensing negotiations could leverage the patent's scope; patent expiration around 2020 impacts patent estate valuation.
- Freedom to Operate (FTO): Investigations must consider claims from related patents in the same chemical space.
Conclusion
U.S. Patent 6,811,794 offers broad coverage over specific pharmaceutical compounds and related manufacturing methods. While its claims are well-structured, later patents in the same space may narrow its scope or provide alternative claim pathways. Its expiration around 2020 diminishes active patent barriers, potentially opening development opportunities, provided that surrounding patent obstacles are addressed.
Key Takeaways
- The '794 patent covers significant chemical and process intellectual property, but newer patents may challenge its breadth.
- For product development, detailed freedom-to-operate and patent clearance analyses are necessary.
- The patent landscape is active, with derivatives and improved formulations continuously innovated to either escape or extend patent rights.
- Post-2020, the patent's legal protections expire, but related patents may still pose infringement risks.
- Strategic positioning involves monitoring FTO, potential licensing, and considering patent expiration timelines.
FAQs
Q1: Can the '794 patent block the development of similar compounds now that it has expired?
No. With expiration around 2020, the patent no longer provides enforceable rights, allowing competitors to freely develop related compounds, unless other active patents in the space are relevant.
Q2: How does the scope of the independent claims influence patent infringement assessments?
The broader the independent claims' language—covering general chemical structures or methods—the higher the risk of infringement for competitors developing similar products.
Q3: Are there ongoing patent applications related to this patent that might extend its IP protection?
Yes, continuation-in-part applications or divisional filings might extend patent life or broaden claims within the same chemical space.
Q4: Which key factors determine the patentability of similar compounds or processes today?
Novelty over prior art, inventive step, and non-obviousness given the existing patent landscape and prior disclosures.
Q5: What strategies can companies use to design around these patent claims?
Developing chemical derivatives outside the scope of the claims, using alternative synthesis methods, or designing new formulation approaches that avoid claim limitations.
References:
- U.S. Patent & Trademark Office, "Patent Classification," 2023.
- Patent landscape analyses, proprietary reports, 2022.
- FDA guidance documents, 2021.
- Public patent records and citations, USPTO database.
