United States Patent 5,527,521: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 5,527,521, titled "Microbubble Contrast Agents," is a significant patent in the field of diagnostic imaging, particularly involving the use of microbubbles as contrast agents. This patent, assigned to DuPont Merck Pharmaceutical Company (later known as DuPont Contrast Imaging, Inc.), was granted on June 18, 1996. Here, we will delve into the scope, claims, and the broader patent landscape surrounding this invention.
Inventors and Assignees
The patent was invented by Evan C. Unger, Terry Matsunaga, and other contributors, with the assignee being DuPont Merck Pharmaceutical Company[4].
Background and Context
The invention pertains to the development of microbubble contrast agents used in diagnostic imaging techniques such as ultrasound and magnetic resonance imaging (MRI). These agents enhance the visibility of structures within the body, allowing for more accurate diagnoses.
Scope of the Invention
The patent describes methods and compositions for preparing gas-filled liposomes, which are microscopic vesicles composed of a lipid bilayer. These liposomes are filled with a gas, such as air or a perfluorocarbon, and are designed to be stable and biocompatible. The scope includes the preparation, use, and administration of these microbubbles for diagnostic and potentially therapeutic applications[4].
Claims
The patent includes multiple claims that define the scope of the invention. Here are some key aspects:
- Composition Claims: These claims describe the composition of the gas-filled liposomes, including the types of lipids and gases used[4].
- Method Claims: These claims outline the methods for preparing the microbubbles, including the steps involved in forming the liposomes and filling them with gas[4].
- Use Claims: These claims specify the use of the microbubbles in diagnostic imaging, such as ultrasound and MRI[4].
Claim Scope and Its Implications
The claim scope of this patent is critical in defining the protection it offers. A well-defined claim scope ensures that the patent is neither too broad nor too narrow. For instance, overly broad claims can be easier to invalidate, as they may not meet the written description requirement or may fall under the abstract idea exception[3].
In the case of US Patent 5,527,521, the claims are anchored to specific embodiments described in the specification, which helps in avoiding the pitfalls of overly broad claims. This approach ensures that the patent provides robust protection while minimizing the risk of invalidation.
Patent Landscape
The patent landscape surrounding US Patent 5,527,521 is complex and involves several related patents and technologies.
- Related Patents: There are several patents that are related to this invention, including US Patent 6,146,657, which also deals with gas-filled liposomes for diagnostic and therapeutic applications. These patents form a continuum of research and development in the field of microbubble contrast agents[4].
- Prior Art: The patent cites several prior art references, indicating the existing state of the art at the time of the invention. This includes patents related to liposomes, contrast agents, and diagnostic imaging techniques[4].
- Competitors and Collaborators: Companies like Imarx Pharmaceutical Corp. and other entities in the diagnostic imaging sector have also developed similar technologies, contributing to the rich patent landscape in this field[4].
Regulatory and Legal Aspects
The patent has undergone various regulatory and legal processes. For example, there was a patent term restoration application for Definity (the commercial name of the microbubble contrast agent), which was approved by the FDA[5].
Impact on Diagnostic Imaging
The invention described in US Patent 5,527,521 has significantly impacted the field of diagnostic imaging. Microbubble contrast agents have improved the sensitivity and specificity of ultrasound and MRI, enabling better visualization of blood flow and tissue characteristics. This has led to more accurate diagnoses and improved patient outcomes.
Economic and Commercial Implications
The commercial success of Definity and similar products has been substantial. These contrast agents have become essential tools in medical imaging, generating significant revenue for pharmaceutical and imaging companies. The patent protection provided by US Patent 5,527,521 has been crucial in safeguarding the intellectual property and market position of the inventors and assignees.
Future Developments and Trends
The field of microbubble contrast agents continues to evolve with advancements in materials science, nanotechnology, and imaging techniques. Future developments may include targeted microbubbles for specific diseases, improved stability and biocompatibility, and integration with other diagnostic modalities.
Key Takeaways
- Invention Scope: The patent covers the preparation, use, and administration of gas-filled liposomes as contrast agents in diagnostic imaging.
- Claim Scope: The claims are well-defined and anchored to specific embodiments, ensuring robust protection without the risk of invalidation.
- Patent Landscape: The patent is part of a broader landscape involving related patents, prior art, and competitors in the diagnostic imaging sector.
- Regulatory and Legal: The patent has undergone regulatory approvals and legal processes, including patent term restoration.
- Impact: The invention has significantly improved diagnostic imaging capabilities, leading to better patient outcomes and commercial success.
FAQs
What is the primary use of the microbubble contrast agents described in US Patent 5,527,521?
The primary use is in diagnostic imaging techniques such as ultrasound and MRI to enhance the visibility of structures within the body.
Who are the inventors of US Patent 5,527,521?
The inventors include Evan C. Unger, Terry Matsunaga, and other contributors.
What company was assigned the patent?
The patent was assigned to DuPont Merck Pharmaceutical Company (later known as DuPont Contrast Imaging, Inc.).
What are the risks associated with overly broad patent claims?
Overly broad claims can be easier to invalidate due to failure to meet the written description requirement or falling under the abstract idea exception.
How has the invention impacted the field of diagnostic imaging?
The invention has improved the sensitivity and specificity of ultrasound and MRI, enabling better visualization and more accurate diagnoses.
Cited Sources
- United States Patent (19) 11 Patent Number: 6,033,645 - Unger et al.
- Federal Register/Vol. 67, No. 144/Friday, July 26, 2002/Notices - FDA Notice.
- The Importance of Getting the Claim Scope Right in a US Patent Application - Rimon Law.
- United States Patent (19) 11 Patent Number: 6,146,657 - Unger et al.
- Federal Register/Vol. 67, No. 144/Friday, July 26, 2002/Notices - Patent Term Restoration Application.
