United States Patent 8,853,231: A Detailed Analysis
Introduction
United States Patent 8,853,231, titled "Pharmaceutical Compositions Comprising Polymorphic Forms C, B, and Y of Rifaximin," was granted on October 7, 2014, to Alfa Wassermann S.p.A. This patent is significant in the pharmaceutical industry, particularly in the development and manufacture of rifaximin, a broad-spectrum antibiotic.
Background of the Invention
The patent relates to the polymorphic forms C, B, and Y of rifaximin, a compound used in various medicinal preparations. Rifaximin is known for its efficacy in treating gastrointestinal disorders and other infections. The invention focuses on the preparation and use of these polymorphic forms in pharmaceutical compositions[4].
Scope of the Invention
The scope of the patent encompasses several key aspects:
Polymorphic Forms
The patent describes the preparation and characterization of polymorphic forms C, B, and Y of rifaximin. These forms are crucial for the stability, efficacy, and bioavailability of the drug. The inventors have developed specific processes to obtain these polymorphic forms, which are essential for maintaining the drug's therapeutic properties[4].
Pharmaceutical Compositions
The patent includes pharmaceutical compositions that contain these polymorphic forms of rifaximin, along with pharmaceutically acceptable carriers. These compositions are designed for oral and possibly topical use, ensuring the drug is delivered effectively to the target site[4].
Manufacturing Processes
The invention details the manufacturing processes for these polymorphic forms, including the conditions and methods necessary to produce consistent and high-quality drug substances. Standardization of these processes is critical to ensure batch-to-batch consistency and compliance with regulatory requirements[4].
Claims of the Patent
The patent includes 18 claims that define the scope of the invention:
Independent Claims
- Claim 1 describes a pharmaceutical composition comprising a polymorphic form of rifaximin (forms C, B, or Y) and a pharmaceutically acceptable carrier.
- Claim 2 specifies the process for preparing these polymorphic forms.
- Claim 3 outlines the use of these polymorphic forms in the manufacture of medicinal preparations[4].
Dependent Claims
The dependent claims further specify the characteristics of the polymorphic forms, the types of carriers used, and the methods of preparation. These claims provide a detailed description of the invention, ensuring that any variations or improvements fall within the scope of the patent[4].
Patent Landscape
The patent landscape surrounding US 8,853,231 is complex and involves multiple related patents and legal disputes.
Related Patents
This patent is part of a series of continuations and continuations-in-part, linking back to earlier patent applications such as U.S. application Ser. No. 13/041,347 and PCT/EP04/12490. These connections highlight the evolutionary nature of the invention and the extensive research and development involved[4].
Litigation and Infringement
The patent has been involved in several litigation cases, particularly regarding generic versions of rifaximin. For example, Salix Pharmaceuticals, Inc., the sole distributor of Xifaxan® tablets in the United States, has been involved in infringement disputes with generic manufacturers. These cases underscore the importance of this patent in protecting the intellectual property related to rifaximin formulations[5].
Regulatory Compliance
The patent emphasizes the importance of standardizing manufacturing methods to ensure compliance with regulatory requirements. Regulatory bodies require that the manufacturing processes of active principles be standardized and controlled to give homogeneous and sound results in terms of polymorphism of the production batches[1].
Industry Impact
The impact of this patent on the pharmaceutical industry is significant:
Innovation
The development of specific polymorphic forms of rifaximin has advanced the field of pharmaceuticals by providing more stable and effective drug formulations.
Market Protection
The patent protects the intellectual property of Alfa Wassermann S.p.A., preventing unauthorized use and ensuring that the company can recoup its investment in research and development.
Legal Precedents
The litigation surrounding this patent sets legal precedents for future cases involving pharmaceutical patents, particularly in the context of generic drug approvals and patent infringement.
Key Takeaways
- Polymorphic Forms: The patent focuses on the preparation and use of polymorphic forms C, B, and Y of rifaximin.
- Pharmaceutical Compositions: It includes compositions with these polymorphic forms and pharmaceutically acceptable carriers.
- Manufacturing Processes: Standardized processes are crucial for ensuring batch-to-batch consistency and regulatory compliance.
- Patent Landscape: The patent is part of a complex landscape involving multiple related patents and litigation cases.
- Industry Impact: It has significant implications for innovation, market protection, and legal precedents in the pharmaceutical industry.
Frequently Asked Questions (FAQs)
Q: What is the main subject of United States Patent 8,853,231?
A: The main subject is the pharmaceutical compositions comprising polymorphic forms C, B, and Y of rifaximin.
Q: Who is the assignee of this patent?
A: The assignee is Alfa Wassermann S.p.A.
Q: What is the significance of polymorphic forms in this patent?
A: The polymorphic forms are crucial for the stability, efficacy, and bioavailability of rifaximin.
Q: Are there any ongoing legal disputes related to this patent?
A: Yes, there have been several litigation cases involving infringement disputes related to generic versions of rifaximin.
Q: How does this patent impact the pharmaceutical industry?
A: It advances the field through innovation, protects intellectual property, and sets legal precedents for future cases.
Cited Sources
- United States Patent and Trademark Office. US10703763.pdf.
- Insight.RPXcorp.com. Case 1:20-cv-00430-RGA Document 59 Filed 11/13/20 Page 1 of 52.
- DigitalCommons.TouroLaw.edu. Mastering Patent Claim Construction.
- United States Patent and Trademark Office. US8853231.pdf.
- Insight.RPXcorp.com. in the united states district court for the district of delaware salix ....
