Understanding the Scope and Claims of United States Patent 5,541,206
Introduction
United States Patent 5,541,206, filed on April 25, 1995, is a significant patent in the field of pharmaceuticals, particularly for its role in the development of retroviral protease inhibitors. This patent is crucial for understanding the treatment of HIV and other retroviral diseases.
Background and Context
The patent in question is associated with ritonavir, a protease inhibitor used in the treatment of HIV/AIDS. Protease inhibitors are a class of antiretroviral drugs that block the protease enzyme, which the HIV virus needs to replicate[1].
Patent Overview
Title and Description
The patent titled "Retroviral protease inhibiting compounds" describes ritonavir and its analogous compounds, their preparation, and pharmaceutical compositions. It outlines the chemical structure and synthesis of these compounds, which are designed to inhibit the protease enzyme of retroviruses[2][5].
Claims and Scope
Independent and Dependent Claims
The patent includes multiple claims that define the scope of the invention. Independent claims typically describe the broadest aspects of the invention, while dependent claims narrow down the scope by adding specific details.
- Independent Claims: These claims define the ritonavir compound, its chemical structure, and its use as a retroviral protease inhibitor.
- Dependent Claims: These claims specify various aspects such as the preparation methods, pharmaceutical compositions, and dosages of the ritonavir compound[2][5].
Chemical Structure and Synthesis
The patent details the chemical structure of ritonavir and its synthesis process. This includes the specific chemical reactions and reagents used to produce the compound, which is essential for reproducing the invention[2].
Patent Landscape
Assignees and Ownership
The patent was originally assigned to Abbott Laboratories, a major pharmaceutical company. The assignee plays a crucial role in the development, marketing, and protection of the patented invention[1].
Related Patents and Prior Art
The patent landscape for ritonavir includes numerous other patents related to protease inhibitors and HIV treatment. These patents often build upon or intersect with the claims of US Patent 5,541,206. For example, other patents may cover different aspects of ritonavir, such as new formulations, dosages, or methods of use[1].
Statistical Analysis and Trends
Patent Filings Over Time
The number of patents filed for ritonavir and related compounds has increased over the years, reflecting ongoing research and development in the field. For instance, the period from 2001 to 2003 saw a significant increase in patent filings related to ritonavir[1].
Geographical Distribution
Most patent applications for ritonavir and similar compounds are filed in the United States and the European Patent Office. This trend indicates the global importance of these inventions and the competitive landscape in pharmaceutical research[1].
Importance of Patentability Searches
Understanding the Invention
Before filing a patent, a thorough understanding of the invention is crucial. This involves articulating the purpose, functionality, and distinguishing characteristics of the invention, such as those described in US Patent 5,541,206[3].
Conducting the Search
A patentability search involves using keyword and classification-based searches to identify relevant prior art. For ritonavir, using both the chemical name and its common name (e.g., "ritonavir" and "Norvir") can uncover a broader range of relevant patents[3].
Strategic Positioning and Defensibility
Competitive Landscape
Understanding the competitive landscape is vital for positioning patents effectively. By analyzing existing patents and identifying gaps, inventors can ensure broader protection and reduce the likelihood of design-arounds by competitors[3].
Enhanced Defensibility
A robust patent application, informed by a comprehensive search, is better equipped to withstand challenges regarding its validity and scope. This is particularly important in the pharmaceutical industry, where patent disputes are common[3].
Regulatory Aspects
FDA and Orange Book Listings
Patents related to ritonavir, including US Patent 5,541,206, are listed in the FDA's Orange Book. This compilation provides information on drug product patents, drug substance patents, and method-of-use patents, which is critical for generic drug manufacturers and for determining market exclusivity[4].
Exclusivity and Generic Competition
The patent and exclusivity information in the Orange Book helps in understanding the timing of generic competition. For example, the market exclusivity period for drugs like ritonavir can range from several years, impacting when generic versions can be approved and marketed[4].
Key Takeaways
- US Patent 5,541,206 is a foundational patent for ritonavir, a protease inhibitor used in HIV treatment.
- Claims and Scope: The patent includes detailed descriptions of the chemical structure, synthesis, and pharmaceutical compositions of ritonavir.
- Patent Landscape: The patent is part of a larger landscape of protease inhibitors and HIV treatments, with numerous related patents and ongoing research.
- Importance of Patentability Searches: Thorough searches are essential for understanding prior art and positioning patents effectively.
- Regulatory Aspects: The patent is listed in the FDA's Orange Book, influencing market exclusivity and generic competition.
Frequently Asked Questions (FAQs)
Q: What is the primary use of ritonavir as described in US Patent 5,541,206?
A: Ritonavir is primarily used as a retroviral protease inhibitor in the treatment of HIV/AIDS.
Q: Who was the original assignee of US Patent 5,541,206?
A: The original assignee was Abbott Laboratories.
Q: How does the patent landscape for ritonavir reflect the broader trends in pharmaceutical research?
A: The patent landscape shows an increase in filings over time, with a significant presence of large pharmaceutical companies and universities, and a high rate of PCT applications.
Q: What is the role of the FDA's Orange Book in relation to US Patent 5,541,206?
A: The Orange Book lists patents related to drug products, including US Patent 5,541,206, providing information on patent expiration dates and market exclusivity.
Q: Why are patentability searches important for inventions like ritonavir?
A: Patentability searches help in understanding prior art, positioning patents effectively, and ensuring the defensibility of the patent against potential challenges.
Sources:
- KEI Online: USPTO issued patents mentioning ritonavir in a patent claim.
- PubChem: Retroviral protease inhibiting compounds - Patent US-5541206-A.
- TT Consultants: Understanding Patentability Searches: Importance, Process, and Best Practices.
- USPTO: USPTO-FDA Report on Drug Patent and Exclusivity.
- Unified Patents Portal: US-5541206-A - Ritonavir Analogous Compound Useful as Retroviral Protease Inhibitor.
