United States Patent 4,727,064: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 4,727,064, titled "Pharmaceutical preparations containing cyclodextrin derivatives," was issued on February 23, 1988, to Dr. Josef Pitha. This patent is significant in the field of pharmaceuticals, particularly in the use of cyclodextrins to enhance the solubility and stability of drugs.
Background
Cyclodextrins are cyclic oligosaccharides that can form inclusion complexes with various substances, making them useful in pharmaceutical formulations. The patent builds on earlier research and innovations in the field, as highlighted in works such as J. Szejtli’s "Cyclodextrins and Their Inclusion Complexes"[2].
Scope of the Patent
The patent focuses on the development of pharmaceutical preparations that utilize cyclodextrin derivatives to improve the solubility and stability of drugs that are otherwise insoluble or sparingly soluble in water. Here are the key aspects of the patent's scope:
Cyclodextrin Derivatives
The patent specifies the use of various cyclodextrin derivatives, including hydroxypropyl, hydroxyethyl, dihydroxypropyl, glucosyl, and maltosyl derivatives of α-, β-, and γ-cyclodextrins. These derivatives are crucial for enhancing the solubilizing and stabilizing effects on drugs[4].
Drug Complexes
The invention involves creating amorphous, water-soluble complexes of drugs with cyclodextrin derivatives. These complexes are designed to improve the bioavailability and stability of the drugs, making them more effective and easier to administer[4].
Applications
The patent covers a wide range of applications, including pharmaceutical, food, cosmetic, and agricultural preparations. The cyclodextrin complexes can be used to solubilize and stabilize lipophilic and/or water-labile active ingredients in these various fields[1][4].
Claims of the Patent
The patent includes several claims that define the scope of the invention:
Composition Claims
The patent claims compositions consisting of a drug with low water solubility and a cyclodextrin derivative. These compositions are characterized by their amorphous, water-soluble nature[4].
Method Claims
The patent also claims methods for preparing these compositions, including the steps of mixing the drug with a cyclodextrin derivative and forming an amorphous complex[4].
Use Claims
Claims are made for the use of these compositions in various applications, such as pharmaceuticals, food additives, cosmetic additives, and agrochemicals[1][4].
Patent Landscape
The patent landscape surrounding U.S. Patent 4,727,064 is complex and involves several key players and developments:
Prior Art and Interferences
The patent was part of a patent interference case (Interference 102,413) involving Dr. Josef Pitha and Dr. Bernd W. Muller and Dr. Ulrich Brauns. This case highlighted the competitive nature of innovations in cyclodextrin technology[2].
Related Patents and Applications
Other patents, such as U.S. Patent 4,596,795 and U.S. Patent 5,472,954, also deal with cyclodextrin complexation and related applications. These patents demonstrate the ongoing research and development in this field[1][4].
Industry Impact
The use of cyclodextrins in pharmaceutical formulations has become a significant area of research and development. Major pharmaceutical companies and academic institutions have been actively involved in patenting innovations related to cyclodextrin complexes, as seen in the broader patent landscape for rare and Alzheimer’s diseases[3].
Technical Details and Innovations
The patent introduces several technical innovations:
Amorphous Complexes
The formation of amorphous, water-soluble complexes is a key innovation. These complexes enhance the solubility and stability of drugs, making them more effective and easier to administer[4].
Cyclodextrin Derivatives
The use of specific cyclodextrin derivatives with a molar degree of substitution between 0.05 and 10 is highlighted. These derivatives are crucial for the solubilizing and stabilizing effects[1][4].
Commercial and Practical Implications
The practical implications of this patent are significant:
Improved Drug Delivery
The ability to solubilize and stabilize drugs that are otherwise insoluble or sparingly soluble in water has improved drug delivery systems. This enhances the bioavailability and efficacy of these drugs[4].
Broader Applications
The technology is not limited to pharmaceuticals but also extends to food, cosmetic, and agricultural applications, where similar solubility and stability issues are addressed[1][4].
Legal and Regulatory Aspects
The patent has undergone legal scrutiny, particularly in the context of patent interference cases. The decision on motions and the final judgment in the interference case between Pitha and Muller highlight the legal complexities involved in patent disputes[2].
Conclusion and Future Directions
U.S. Patent 4,727,064 has played a pivotal role in advancing the use of cyclodextrin derivatives in pharmaceutical and related fields. The ongoing research and development in this area continue to expand the applications and improve the efficacy of these complexes.
Key Takeaways
- Cyclodextrin Derivatives: The patent focuses on the use of specific cyclodextrin derivatives to enhance drug solubility and stability.
- Amorphous Complexes: The formation of amorphous, water-soluble complexes is a key innovation.
- Broad Applications: The technology extends beyond pharmaceuticals to food, cosmetics, and agriculture.
- Legal and Regulatory: The patent has been part of significant legal cases, highlighting the competitive nature of innovations in this field.
Frequently Asked Questions (FAQs)
What is the main innovation of U.S. Patent 4,727,064?
The main innovation is the formation of amorphous, water-soluble complexes of drugs with cyclodextrin derivatives to enhance solubility and stability.
What types of cyclodextrin derivatives are used in this patent?
The patent specifies the use of hydroxypropyl, hydroxyethyl, dihydroxypropyl, glucosyl, and maltosyl derivatives of α-, β-, and γ-cyclodextrins.
What are the practical implications of this patent?
The patent improves drug delivery systems by enhancing the bioavailability and efficacy of drugs that are otherwise insoluble or sparingly soluble in water.
Are the applications of this patent limited to pharmaceuticals?
No, the technology also extends to food, cosmetic, and agricultural applications.
What legal issues has this patent been involved in?
The patent was part of a patent interference case (Interference 102,413) involving Dr. Josef Pitha and Dr. Bernd W. Muller and Dr. Ulrich Brauns.
Cited Sources:
- US5472954A - Cyclodextrin complexation - Google Patents
- Pitha V. Muller et al, 07264726 | Casetext
- A novel approach to understand patents from the drug discovery ... - bioRxiv
- US4727064A - Pharmaceutical preparations containing cyclodextrin derivatives - Google Patents
