United States Patent 6,143,771: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 6,143,771, owned by AstraZeneca AB, is a significant patent in the pharmaceutical industry, particularly related to the drug product NEXIUM® I.V. (esomeprazole sodium for injection). This analysis delves into the scope, claims, and the broader patent landscape surrounding this patent.
Background of the Patent
The patent in question pertains to esomeprazole, a proton pump inhibitor used to treat various gastrointestinal conditions. The specific formulation at issue is NEXIUM® I.V., which was approved by the FDA on March 31, 2005, for commercial use and sale[1][2].
Scope of the Patent
The scope of U.S. Patent 6,143,771 is defined by its claims, which are critical in determining the patent's coverage and validity. Here are some key aspects:
Claim Language and Scope
Patent claims are the legal boundaries that define the invention. For U.S. Patent 6,143,771, the claims are centered around the active ingredient esomeprazole and its specific formulations. The patent scope can be measured using metrics such as independent claim length and independent claim count, which are indicators of patent breadth and clarity[3].
Product Definition
Under 35 U.S.C. § 156(f), the term "product" includes drug products, medical devices, food additives, and color additives subject to regulation under the Federal Food, Drug, and Cosmetic Act (FFDCA). In this case, the product is a drug product, specifically the active ingredient esomeprazole in its sodium salt form[1].
Claims Analysis
Independent Claims
Independent claims are those that stand alone and do not depend on other claims. For U.S. Patent 6,143,771, the independent claims are crucial as they define the core invention. These claims typically include the composition of the drug product, its method of use, and any specific formulations.
Dependent Claims
Dependent claims build upon the independent claims and provide additional details or limitations. These claims help to narrow down the scope of the invention and can include variations such as different dosages, formulations, or methods of administration.
Patent Term Extension (PTE) Analysis
Eligibility Under Hatch-Waxman
The Hatch-Waxman Act allows for patent term extension (PTE) to compensate for the time spent in regulatory review. However, for U.S. Patent 6,143,771, the application for PTE was denied because the approval of NEXIUM® I.V. did not constitute the first permitted commercial marketing or use of the product. This decision was based on the fact that a previous version of esomeprazole had already been approved, thus not meeting the criteria for PTE under 35 U.S.C. § 156[1][4].
Regulatory Review Period
The regulatory review period is a critical factor in determining PTE eligibility. For human drugs, this period includes the time from the submission of a New Drug Application (NDA) to the FDA's approval. However, in the case of U.S. Patent 6,143,771, the review period did not qualify for PTE because it did not represent the first commercial marketing or use of the product[4].
Patent Landscape
Pharmaceutical Patents and Regulatory Approval
Pharmaceutical patents often face unique challenges due to the extensive regulatory approval process required by the FDA. This process can significantly reduce the effective patent term, making PTE a crucial mechanism to restore some of the lost time. However, the rules governing PTE are stringent, and only one patent may be extended based on the regulatory review period for the active ingredient[4].
Competition and Generic Entry
The Hatch-Waxman Act balances innovation incentives with generic entry. While PTE extends the patent term to compensate for regulatory delays, it also facilitates generic entry once the extended term expires. This balance is designed to encourage new drug research while ensuring that generic drugs can enter the market in a timely manner[4].
Litigation and Enforcement
Patent Infringement
Patent litigation is a common aspect of the pharmaceutical industry, especially when generic manufacturers seek to enter the market. For U.S. Patent 6,143,771, any infringement claims would need to be based on the specific claims of the patent, which define the scope of protection. Litigation often involves complex claim constructions and reviews at both the district and appellate court levels[5].
Metrics for Patent Scope
Independent Claim Length and Count
Research has shown that metrics such as independent claim length (ICL) and independent claim count (ICC) can be useful in measuring patent scope. These metrics indicate the breadth and clarity of the patent claims. For U.S. Patent 6,143,771, analyzing these metrics could provide insights into the patent's scope and its potential for litigation or licensing[3].
Conclusion
U.S. Patent 6,143,771 is a significant patent in the pharmaceutical sector, particularly due to its association with the drug product NEXIUM® I.V. The patent's scope is defined by its claims, which are critical in determining its coverage and validity. The denial of PTE for this patent highlights the stringent criteria under the Hatch-Waxman Act and the importance of understanding the regulatory review process.
Key Takeaways
- Patent Scope: Defined by independent and dependent claims.
- PTE Eligibility: Denied due to prior approval of a similar product.
- Regulatory Review: Critical in determining PTE eligibility.
- Patent Landscape: Balances innovation incentives with generic entry.
- Litigation: Involves complex claim constructions and reviews.
- Metrics for Scope: Independent claim length and count are useful indicators.
FAQs
What is the main product covered by U.S. Patent 6,143,771?
The main product covered is NEXIUM® I.V., which is esomeprazole sodium for injection.
Why was the application for PTE denied for U.S. Patent 6,143,771?
The application was denied because the approval of NEXIUM® I.V. did not constitute the first permitted commercial marketing or use of the product.
What is the maximum term extension under the Hatch-Waxman Act?
The maximum term extension is five years, provided that the extension does not result in a total remaining patent term of more than 14 years from the date of regulatory approval.
How is the regulatory review period calculated for PTE?
The regulatory review period includes the time from the submission of a New Drug Application (NDA) to the FDA's approval.
What metrics can be used to measure the scope of a patent?
Metrics such as independent claim length (ICL) and independent claim count (ICC) can be used to measure the scope and clarity of patent claims.
Sources
- United States Patent and Trademark Office. Determination of Ineligibility for Patent Term Extension Under 35 U.S.C. § 156 for U.S. Patent No. 6,143,771. July 28, 2005.
- United States Patent and Trademark Office. Decision Denying Application for Patent Term Extension for U.S. Patent No. 6,143,771.
- Hoover Institution. Patent Claims and Patent Scope. August 18, 2016.
- Alacrita. Pharmaceutical Patent Term Extension: An Overview.
- United States District Court for the Eastern District. Litigation Documents: Esomeprazole Sodium I.V. Products.
