Analyzing the Scope and Claims of United States Patent 4,894,240
Introduction
United States Patent 4,894,240, titled "Delayed Release Diltiazem Bead," is a significant patent in the pharmaceutical industry, particularly in the development of cardiovascular medications. This patent, issued to the inventors, describes a formulation for a delayed-release diltiazem bead, which is crucial for the treatment of hypertension and other cardiovascular conditions.
Background of the Patent
The patent 4,894,240 was granted for a formulation that allows for the controlled release of diltiazem, a calcium channel blocker. This formulation is designed to provide a specific release profile, ensuring that the medication is delivered in a manner that maintains therapeutic levels over an extended period.
Scope of the Patent
Claims Overview
The patent includes several claims that define the scope of the invention. Here are the key aspects:
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Claim 1: This claim describes the delayed-release diltiazem bead, specifying that it releases a certain percentage of the total diltiazem within a defined time frame. For instance, the claim may specify that not less than 45% of the total diltiazem is released after 24 hours[1][4].
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Claim Coverage: The claims cover the composition of the bead, the method of preparation, and the in-vitro dissolution profile. This ensures that any generic or competing product must either not infringe these claims or challenge the patent's validity[1].
In-Vitro Dissolution Profile
A critical aspect of the patent is the in-vitro dissolution profile, which describes how the diltiazem is released over time. This profile is a key differentiator and is used to determine whether other products infringe on the patent. For example, the '584 patent, related to this one, specifies that from 0-45% of the total diltiazem is released after 18 hours and not less than 45% is released after 24 hours[1].
Patent Landscape
Related Patents
The patent landscape surrounding 4,894,240 includes other related patents that cover similar formulations and release profiles. For instance:
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U.S. Patent 5,470,584: This patent, also related to diltiazem formulations, was issued later and claims a specific in-vitro dissolution profile. It has been involved in litigation regarding infringement and validity[1].
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U.S. Patent 5,002,776: This patent also discloses a delayed-release diltiazem bead and has been referenced in antitrust litigation involving generic drug manufacturers[1].
Litigation and Infringement
The patent has been involved in significant litigation, particularly under the Hatch-Waxman Amendments. These amendments provide a framework for generic drug manufacturers to challenge pioneer drug makers' patents. For example, Andrx Pharmaceuticals filed a Paragraph IV certification challenging the '584 patent, which led to a lawsuit and eventual settlement[1].
Patent Analytics and Claim Coverage
To understand the full scope and value of the patent, patent analytics tools are essential. Here’s how these tools can be applied:
Claim Coverage Matrix
A Claim Coverage Matrix helps in identifying which patents and claims are actively protecting the intellectual property. This matrix can categorize patents by claims and overarching scope concepts, making it easier to filter, search, and analyze large numbers of patent claims concurrently[3].
Claim Charts
Interactive claim charts generated by tools like ClaimScape® software can help technical experts review patent coverage. These charts can determine whether a particular scope concept is applicable to a target product or method, highlighting gaps in current coverage and future design opportunities[3].
Economic Value of the Patent
The economic value of a patent like 4,894,240 can be substantial. Here are some points to consider:
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Market Impact: Patents in the pharmaceutical industry can have a significant market impact, especially if they cover a widely used medication. The exclusive rights granted by the patent can lead to higher revenues for the patent holder[2].
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Litigation Costs and Incentives: The Hatch-Waxman Amendments provide incentives for generic manufacturers to challenge patents, but this also involves substantial litigation costs. The first generic manufacturer to successfully challenge a patent and gain FDA approval is awarded a 180-day period of exclusive marketing rights[1].
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Purchase and Licensing: Patents can be bought and sold, and their value can range widely. For example, the mean price per patent document can be around $483,924, with some deals reaching millions of dollars per patent[2].
Key Takeaways
- Specific Release Profile: The patent 4,894,240 is characterized by a specific in-vitro dissolution profile that defines how diltiazem is released over time.
- Litigation and Infringement: The patent has been involved in significant litigation under the Hatch-Waxman Amendments, highlighting the importance of patent validity and infringement challenges.
- Economic Value: The patent holds substantial economic value due to its market impact and the exclusive rights it grants.
- Patent Analytics: Tools like Claim Coverage Matrix and Claim Charts are crucial for understanding and managing the patent landscape.
FAQs
Q1: What is the main claim of United States Patent 4,894,240?
The main claim of the patent describes a delayed-release diltiazem bead that releases a specific percentage of diltiazem within a defined time frame.
Q2: How does the Hatch-Waxman Amendment affect generic drug manufacturers?
The Hatch-Waxman Amendment provides an incentive for generic drug manufacturers to challenge pioneer drug makers' patents by awarding a 180-day period of exclusive marketing rights to the first generic manufacturer to file a Paragraph IV certification and gain FDA approval.
Q3: What is the significance of the in-vitro dissolution profile in the patent?
The in-vitro dissolution profile is critical as it defines the release characteristics of the diltiazem bead, distinguishing it from other formulations and serving as a basis for determining infringement.
Q4: How can patent analytics tools help in managing patents like 4,894,240?
Patent analytics tools like Claim Coverage Matrix and Claim Charts help in categorizing and analyzing patent claims, identifying gaps in coverage, and highlighting future design opportunities.
Q5: What is the economic value of a patent like 4,894,240?
The economic value of such a patent can be substantial, involving significant market impact, litigation costs, and potential purchase or licensing values ranging from hundreds of thousands to millions of dollars.
Sources
- In re Cardizem CD Antitrust Litigation - Casetext
- The Value of a Patent - Perpetual Motion Patents
- Patent Analytics - SLWIP
- Diltiazem Formulation - Google Patents