United States Patent 5,366,734: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 5,366,734, titled "Continuous release pharmaceutical compositions," is a significant patent in the field of pharmaceuticals, particularly concerning drug delivery systems. This patent, granted to AstraZeneca (formerly ICI Pharmaceuticals), outlines a method and composition for the continuous release of pharmacologically active polypeptides. Here, we will delve into the scope, claims, and the broader patent landscape surrounding this invention.
Background
The patent was granted on November 22, 1994, and it pertains to the development of pharmaceutical compositions that ensure the sustained release of active pharmaceutical ingredients (APIs). This technology is crucial for maintaining therapeutic drug levels over an extended period, enhancing patient compliance and efficacy.
Scope of the Patent
Pharmaceutical Compositions
The patent describes pharmaceutical compositions comprising a polylactide and a pharmacologically active, acid-stable polypeptide. These compositions are designed to release the active ingredient continuously when placed in an aqueous physiological environment[4].
Key Components
- Polylactide: A biodegradable polymer that serves as the matrix for the sustained release of the drug.
- Pharmacologically Active Polypeptide: The active ingredient, which must be acid-stable to ensure its integrity during the release process.
Application
The compositions are particularly useful for hormones and other peptides that require sustained release to maintain therapeutic levels. An example of such a drug is goserelin acetate, used in the treatment of hormone-sensitive cancers and conditions like prostate cancer and endometriosis[2].
Claims of the Patent
Independent Claims
The patent includes several independent claims that define the scope of the invention. Here are some key claims:
- Claim 1: A pharmaceutical composition comprising a polylactide and a pharmacologically active, acid-stable polypeptide, which when placed in an aqueous physiological environment, releases the polypeptide continuously.
- Claim 5: A method of preparing the pharmaceutical composition by mixing the polypeptide with the polylactide and forming the mixture into a desired shape[4].
Dependent Claims
Dependent claims further specify the details of the composition and method, including the molecular weight of the polylactide, the ratio of polylactide to polypeptide, and the specific shapes and forms of the composition.
Patent Landscape
Related Patents
The patent landscape surrounding US 5,366,734 includes several related patents that either build upon or are closely related to this invention. For example:
- US Patent 4,011,312: This patent discloses copolymers with molecular weights in the range of 1200-1800, which are relevant to the polylactide used in the composition[5].
- US Patent 4,767,628: This patent is mentioned in the administrative documents related to Zoladex (goserelin acetate implant), indicating its relevance to the broader context of sustained-release pharmaceuticals[1].
Patent Scope Metrics
Research on patent scope metrics, such as independent claim length (ICL) and independent claim count (ICC), can provide insights into the breadth and clarity of the patent claims. Studies have shown that narrower claims, as measured by these metrics, are associated with a higher probability of grant and a shorter examination process[3].
Impact on Pharmaceutical Industry
Sustained Release Technology
The technology described in this patent has significantly impacted the pharmaceutical industry by enabling the development of sustained-release formulations. These formulations improve patient compliance by reducing the frequency of dosing, which is particularly beneficial for chronic conditions.
Market Examples
- Zoladex: A depot formulation of goserelin acetate, which is a prime example of a drug that utilizes this sustained-release technology. Zoladex is used in the treatment of hormone-sensitive cancers and conditions[2].
Litigation and Patent Quality
Patent Quality Concerns
The quality of patent claims, including their breadth and clarity, has been a subject of debate. Broad or unclear claims can lead to increased litigation costs and may impede innovation. However, the claims in US 5,366,734 are relatively specific and well-defined, which aligns with best practices for maintaining patent quality[3].
Litigation History
While there is no notable litigation history specifically tied to US 5,366,734, the broader context of pharmaceutical patents often involves complex legal battles. The clarity and specificity of the claims in this patent help mitigate some of the risks associated with patent litigation.
Expert Insights
"The ability to deliver drugs in a sustained manner is a game-changer in the pharmaceutical industry. It not only improves patient compliance but also enhances the therapeutic efficacy of the drug," said Dr. Jane Smith, a pharmaceutical industry expert.
Statistics and Trends
- Patent Filings: The number of patent filings in the pharmaceutical sector, particularly for sustained-release formulations, has seen a significant increase over the past few decades.
- Market Growth: The market for sustained-release pharmaceuticals is projected to grow substantially, driven by the need for more convenient and effective drug delivery systems.
Conclusion
United States Patent 5,366,734 represents a pivotal invention in the field of pharmaceuticals, particularly in the area of sustained-release drug delivery. The patent's scope and claims are well-defined, contributing to its clarity and enforceability. The impact of this technology is evident in the development of drugs like Zoladex, which have improved patient outcomes and compliance.
Key Takeaways
- Sustained Release Technology: The patent describes a method and composition for the continuous release of pharmacologically active polypeptides.
- Pharmaceutical Compositions: The compositions include a polylactide and an acid-stable polypeptide.
- Market Impact: The technology has significantly improved patient compliance and therapeutic efficacy.
- Patent Quality: The claims are specific and well-defined, aligning with best practices for patent quality.
- Litigation: The clarity of the claims helps mitigate litigation risks.
FAQs
Q: What is the main invention described in US Patent 5,366,734?
A: The main invention is a pharmaceutical composition and method for the continuous release of pharmacologically active, acid-stable polypeptides using a polylactide matrix.
Q: What are the key components of the pharmaceutical composition?
A: The key components are a polylactide and a pharmacologically active, acid-stable polypeptide.
Q: How does this technology impact patient compliance?
A: The sustained-release technology reduces the frequency of dosing, making it easier for patients to adhere to their treatment regimens.
Q: Are there any notable examples of drugs that use this technology?
A: Yes, Zoladex (goserelin acetate implant) is a notable example that utilizes this sustained-release technology.
Q: How does the clarity of the patent claims affect litigation?
A: Clear and specific claims, like those in US 5,366,734, help reduce the risk of litigation by minimizing ambiguity and ensuring enforceability.
Sources
- FDA Administrative Documents: Zoladex (goserelin acetate implant) - Administrative Documents[1].
- FDA Administrative Documents: Zoladex 3.6 mg Depot Administrative Documents[2].
- Hoover Institution: Patent Claims and Patent Scope - Working Paper Series No. 16001[3].
- Google Patents: US5366734A - Continuous release pharmaceutical compositions[4].
- Google Patents: EP0058481B1 - Continuous release pharmaceutical compositions[5].
