Detailed Analysis of the Scope and Claims of United States Patent 5,474,756
Introduction
United States Patent 5,474,756, titled "Method for Imaging Mammalian Tissue Using 1-substituted-1,4,7-tricarboxymethyl-1,4,7-triazacyclononane Chelates," was granted on December 12, 1995. This patent is significant in the field of medical imaging, particularly for its contributions to the development of contrast agents used in magnetic resonance imaging (MRI).
Inventors and Assignees
The patent was invented by a team of researchers and assigned to Bracco Suisse SA, a company known for its work in diagnostic imaging agents[5].
Background
The invention addresses the need for effective and safe contrast agents in MRI. Contrast agents enhance the visibility of internal body structures during MRI scans, aiding in the diagnosis of various medical conditions.
Summary of the Invention
The patent describes a method for imaging mammalian tissue using specific chelates of 1-substituted-1,4,7-tricarboxymethyl-1,4,7-triazacyclononane. These chelates are designed to bind with metal ions, typically gadolinium, to create stable and biocompatible contrast agents. The method involves administering these contrast agents to a subject and then performing an MRI scan to visualize the targeted tissues[5].
Claims
The patent includes several claims that define the scope of the invention:
Independent Claims
- Claim 1: A method for imaging mammalian tissue using a contrast agent comprising a 1-substituted-1,4,7-tricarboxymethyl-1,4,7-triazacyclononane chelate.
- Claim 2: The method of claim 1, where the chelate is bound to a gadolinium ion.
- Claim 3: The method of claim 1, where the contrast agent is administered intravenously.
Dependent Claims
- Claim 4: The method of claim 1, where the mammalian tissue is selected from the group consisting of liver, spleen, and lymph nodes.
- Claim 5: The method of claim 1, where the contrast agent is used to diagnose a disease or condition affecting the mammalian tissue.
Detailed Description of the Invention
The patent provides a detailed description of the synthesis and use of the 1-substituted-1,4,7-tricarboxymethyl-1,4,7-triazacyclononane chelates. These chelates are synthesized through a series of chemical reactions that involve substituting the triazacyclononane ring with carboxymethyl groups. The resulting chelates are then complexed with metal ions, such as gadolinium, to form the contrast agents.
Advantages and Benefits
The contrast agents described in the patent offer several advantages:
- Stability and Safety: The chelates are designed to be highly stable and biocompatible, reducing the risk of adverse reactions.
- Enhanced Imaging: The agents provide clear and detailed images of internal body structures, aiding in accurate diagnoses.
- Versatility: The method can be applied to various types of mammalian tissues, including liver, spleen, and lymph nodes[5].
Patent Landscape
The patent landscape surrounding US 5,474,756 is complex and involves several related patents and technologies:
Prior Art
Several prior patents and publications are cited in the background section of the patent, including works by Gansow et al. and Tweedle et al., which relate to the use of chelating agents in medical imaging[1].
Related Patents
Other patents, such as US 7,666,425, also deal with the use of antibodies and biological probes for diagnostic and therapeutic purposes, though they are not directly related to the specific chelates described in US 5,474,756[1].
International Patent Filings
The invention may have been filed in other jurisdictions, given the global nature of the pharmaceutical and diagnostic imaging industries. For example, similar patents might be found in databases of the European Patent Office (EPO), Japan Patent Office (JPO), or World Intellectual Property Organization (WIPO)[4].
Economic and Market Impact
The development and commercialization of the contrast agents described in this patent have significant economic and market implications:
- Market Dominance: Bracco Suisse SA, as the assignee, has a competitive edge in the market for MRI contrast agents.
- Healthcare Impact: The improved safety and efficacy of these agents contribute to better patient outcomes and more accurate diagnoses.
- Research and Development: The patent encourages further research into the development of new contrast agents and imaging techniques.
Legal and Regulatory Aspects
The patent is subject to various legal and regulatory considerations:
- Patent Term: The patent was granted in 1995 and would have expired 20 years from the filing date, assuming no extensions or adjustments.
- Maintenance Fees: The patentee must pay maintenance fees to keep the patent in force[4].
- Litigation and Enforcement: The patent holder can enforce the patent against infringers through legal action.
Conclusion
United States Patent 5,474,756 represents a significant advancement in the field of MRI contrast agents. The detailed analysis of its scope and claims highlights its importance in medical imaging and its impact on the patent landscape.
Key Takeaways
- The patent describes a method for imaging mammalian tissue using specific chelates.
- The chelates are stable, biocompatible, and effective in enhancing MRI images.
- The patent has significant economic and market implications in the diagnostic imaging industry.
- The legal and regulatory aspects of the patent are crucial for its enforcement and maintenance.
Frequently Asked Questions (FAQs)
Q1: What is the main invention described in US 5,474,756?
A1: The main invention is a method for imaging mammalian tissue using 1-substituted-1,4,7-tricarboxymethyl-1,4,7-triazacyclononane chelates as contrast agents.
Q2: Who is the assignee of the patent?
A2: The assignee is Bracco Suisse SA.
Q3: What are the advantages of the contrast agents described in the patent?
A3: The agents are highly stable, biocompatible, and provide clear and detailed images of internal body structures.
Q4: How long does a patent typically last?
A4: A patent typically lasts for 20 years from the filing date, assuming no extensions or adjustments.
Q5: Where can one find more information about similar patents?
A5: Information about similar patents can be found through databases such as the USPTO, EPO, JPO, and WIPO.
Cited Sources
- United States Patent and Trademark Office, "US 7,666,425 B1 - Treatment and Diagnosis of Prostate Cancer," February 23, 2010.
- Canadian Patents Database, "Patent 2569461 Summary - LIPOPHILIC DERIVATIVES OF CHELATE MONOAMIDES," December 29, 2005.
- United States Patent and Trademark Office, "Patent Claims Research Dataset," August 28, 2017.
- United States Patent and Trademark Office, "Search for Patents," October 18, 2018.
- Unified Patents Portal, "US-20090204545-A1 - Method for Imaging Mammalian Tissue Using 1-substituted-1,4,7-tricarboxymethyl-1,4,7-triazacyclononane Chelates," December 12, 1995.
