United States Patent 8,475,841: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
The United States Patent 8,475,841, titled "Controlled Release Metformin Formulations," is a significant patent in the pharmaceutical industry, particularly in the field of diabetes treatment. This patent, owned by Andrx (now part of Takeda Pharmaceuticals), covers specific formulations of metformin, a widely used antidiabetic medication. Here, we will delve into the scope, claims, and the broader patent landscape surrounding this invention.
Background and Inventors
The patent was issued on July 2, 2013, to inventors Xiu Xiu Cheng, Steve Jan, Joseph Chou, and Chih-Ming Chen. It is part of a series of patents related to controlled release metformin formulations, which are crucial for managing blood sugar levels in diabetic patients[2].
Scope of the Patent
The scope of the 8,475,841 patent is defined by its claims, which describe specific formulations and methods for delivering metformin in a controlled release manner. The patent encompasses various aspects, including:
Controlled Release Formulations
The patent details formulations that allow for the controlled release of metformin, which helps in maintaining stable blood sugar levels over an extended period. This is particularly beneficial for patients who require consistent medication management[2].
Composition and Ingredients
The patent specifies the use of metformin in combination with other ingredients to achieve the desired controlled release profile. This includes the use of various excipients, binders, and release-controlling agents[4].
Claims Analysis
The claims of the 8,475,841 patent are critical in defining the scope of protection. Here are some key aspects:
Independent Claims
The independent claims outline the core inventions, including the specific formulations and methods of preparing these formulations. For example, Claim 1 might describe a controlled release metformin formulation comprising metformin hydrochloride, a release-controlling agent, and other excipients[2].
Dependent Claims
Dependent claims further narrow down the scope by specifying particular embodiments or variations of the independent claims. These could include specific concentrations of metformin, types of release-controlling agents, or manufacturing processes[2].
Enablement and Written Description
The patent must meet the enablement and written description requirements under 35 U.S.C. § 112. This means the specification must provide sufficient detail so that a person of ordinary skill in the art can make and use the invention without undue experimentation. The 8,475,841 patent includes detailed descriptions of the formulations, methods of preparation, and examples to support its claims[1][2].
Patent Landscape
The patent landscape surrounding the 8,475,841 patent is complex and involves several related patents and licensing agreements.
Related Patents
Andrx holds a series of patents related to controlled release metformin formulations, including U.S. Patent Nos. 6,790,459, 7,919,116, and 7,959,946. These patents collectively protect various aspects of metformin formulations and their methods of use[2].
Licensing Agreements
Takeda Pharmaceuticals, which acquired Andrx, has licensing agreements with other companies, such as Actavis, for the commercialization of these formulations under the trade name ACTOPLUS MET® XR. These agreements are crucial for the distribution and marketing of the drug products[2].
Litigation and Infringement
Patents like the 8,475,841 are often involved in litigation, particularly when generic manufacturers seek to enter the market. For instance, Mylan's filing of an Abbreviated New Drug Application (ANDA) for a generic version of ACTOPLUS MET® XR led to infringement claims by Takeda and Actavis, alleging that Mylan's actions would infringe on their patents[2].
Metrics for Measuring Patent Scope
The scope of patents like the 8,475,841 can be measured using metrics such as independent claim length and independent claim count. These metrics help in assessing the breadth and clarity of the patent claims. Research has shown that narrower claims tend to have a higher probability of grant and a shorter examination process[3].
Impact on Innovation and Industry
The breadth and validity of patents like the 8,475,841 can significantly impact innovation and industry dynamics. Overly broad patents can increase licensing and litigation costs, potentially diminishing incentives for further innovation. However, well-defined and valid patents can protect intellectual property and encourage continued research and development in the field[3].
Patent Expiration and Generic Launch
The 8,475,841 patent expired on March 20, 2018, which allowed generic manufacturers to enter the market. The expiration of such patents is a critical event in the pharmaceutical industry, as it can lead to increased competition and reduced drug prices[5].
"Patent scope is one of the important aspects in the debates over ‘patent quality.’ The purported decrease in patent quality over the past decade or two has supposedly led to granting patents of increased breadth (or ‘overly broad’ patents), decreased clarity, and questionable validity."
- Hoover Institution[3]
Key Takeaways
- Scope and Claims: The 8,475,841 patent covers specific controlled release metformin formulations and methods, defined by its independent and dependent claims.
- Enablement and Written Description: The patent must meet the enablement and written description requirements to ensure that a person of ordinary skill in the art can make and use the invention.
- Patent Landscape: The patent is part of a series of related patents and is subject to licensing agreements and potential litigation.
- Metrics for Measuring Scope: Independent claim length and count are useful metrics for assessing the breadth and clarity of patent claims.
- Impact on Innovation: The validity and breadth of the patent can influence innovation and industry dynamics.
- Patent Expiration: The expiration of the patent allowed generic manufacturers to enter the market, potentially increasing competition and reducing drug prices.
Frequently Asked Questions
Q: What is the main subject of the 8,475,841 patent?
A: The main subject is controlled release metformin formulations and their methods of preparation.
Q: Who are the inventors of the 8,475,841 patent?
A: The inventors are Xiu Xiu Cheng, Steve Jan, Joseph Chou, and Chih-Ming Chen.
Q: What is the significance of the patent's expiration date?
A: The expiration date allowed generic manufacturers to produce and market generic versions of the drug, increasing competition and potentially reducing prices.
Q: How does the patent landscape impact the 8,475,841 patent?
A: The patent is part of a series of related patents and is subject to licensing agreements and potential litigation, which can affect its enforcement and commercialization.
Q: What metrics are used to measure the scope of patent claims?
A: Metrics such as independent claim length and independent claim count are used to assess the breadth and clarity of patent claims.
Sources
- Fed. Cir. 2007 - U.S. Court of Appeals for the Federal Circuit, Pharm. Res., Inc. v. Roxane Labs., Inc.
- Case 1:12-cv-00024-DLC - Document 106 Filed 07/12/13, United States District Court for the District of Montana.
- Hoover Institution - Patent Claims and Patent Scope, August 2016.
- Google Patents - US6475521B1 - Biphasic controlled release delivery system for high solubility pharmaceuticals and method.
- Pharsight - Fortamet patent expiration.