United States Patent 5,284,662: A Detailed Analysis of Scope and Claims
Introduction
The United States Patent 5,284,662, titled "Oral osmotic system for slightly soluble active agents," is a significant innovation in the field of pharmaceutical drug delivery systems. This patent, granted on February 8, 1994, addresses the challenges of delivering slightly soluble active agents through an oral osmotic system.
Background of the Invention
Controlled release drug delivery systems have been a focus of pharmaceutical research due to their ability to maintain therapeutic drug concentrations over an extended period, minimizing side effects and improving patient compliance. The patent in question specifically targets the delivery of slightly soluble active agents, which pose unique challenges due to their limited solubility in water[4].
Summary of the Invention
The patent describes an oral sustained release composition designed for slightly soluble pharmaceutically active agents. This system consists of a core containing the active agent, a wall surrounding the core, and a bore or orifice through the wall. The wall is semi-permeable, allowing water to enter the core and push the active agent out through the bore, thereby achieving a controlled release profile[4].
Key Components of the Invention
Core Composition
The core contains the slightly soluble active agent, such as carbamazepine, mixed with osmotic agents, wetting agents, and other excipients. The osmotic agents help to draw water into the core, facilitating the release of the active agent[4].
Semi-Permeable Wall
The semi-permeable wall is crucial for controlling the release rate. It is typically made from materials like cellulose acetate or ethyl cellulose, which allow water to pass through while retaining the active agent inside the core[4].
Bore or Orifice
The bore or orifice is a critical feature that allows the active agent to be released from the core as water enters. The size and shape of the bore can be adjusted to control the release rate of the active agent[4].
Claims of the Patent
Independent Claims
The patent includes several independent claims that define the scope of the invention. These claims specify the composition of the core, the nature of the semi-permeable wall, and the presence of a bore or orifice. For example, Claim 1 describes the oral sustained release composition comprising a core containing a slightly soluble active agent and osmotic agents, surrounded by a semi-permeable wall with a bore[4].
Dependent Claims
Dependent claims further detail the specific components and their roles within the system. These include claims related to the types of osmotic agents, wetting agents, and other excipients that can be used, as well as the materials for the semi-permeable wall and the dimensions of the bore[4].
Patent Scope and Landscape
Patent Scope
The scope of this patent is defined by its claims, which cover a broad range of slightly soluble active agents and various components of the oral osmotic system. The patent's scope is narrowed by the specific requirements for the core composition, the semi-permeable wall, and the bore or orifice. This ensures that the invention is distinct from other controlled release systems and provides a unique solution for delivering slightly soluble drugs[4].
Prior Art and Related Patents
The patent landscape in this area includes other inventions related to controlled release drug delivery systems. For instance, patents like US 5,393,765 describe erodible pharmaceutical compositions for zero-order controlled release, which, although different in mechanism, also aim to achieve controlled drug delivery[1]. The US 20030219485A1 patent describes an oral osmotic controlled drug delivery system, which shares some similarities but is distinct in its application and design[2].
Impact and Applications
Pharmaceutical Industry
This patent has significant implications for the pharmaceutical industry, particularly in the development of oral drug delivery systems for slightly soluble active agents. It provides a reliable method for maintaining therapeutic drug levels over an extended period, enhancing patient compliance and reducing side effects.
Clinical Benefits
The controlled release profile achieved by this system can lead to improved therapeutic outcomes by ensuring consistent drug concentrations in the bloodstream. This is particularly beneficial for drugs like carbamazepine, which require stable plasma levels to be effective.
Challenges and Limitations
Formulation Challenges
One of the main challenges in implementing this system is the formulation of the core and the semi-permeable wall. The choice of osmotic agents, wetting agents, and other excipients must be carefully optimized to ensure the desired release profile.
Manufacturing Complexity
The manufacturing process for these systems can be complex, involving the precise creation of the semi-permeable wall and the bore or orifice. This complexity can increase production costs and require specialized equipment.
Future Developments and Innovations
Advancements in Materials
Future developments may focus on new materials for the semi-permeable wall and osmotic agents that can enhance the efficiency and stability of the system.
Combination Therapies
There is potential for integrating this technology with other drug delivery systems to create combination therapies that offer multiple benefits.
Key Takeaways
- The patent describes an oral osmotic system for delivering slightly soluble active agents.
- The system consists of a core, a semi-permeable wall, and a bore or orifice.
- The claims define the scope of the invention, including specific components and their roles.
- The patent has significant implications for the pharmaceutical industry and clinical practice.
- Challenges include formulation and manufacturing complexities.
Frequently Asked Questions (FAQs)
What is the main innovation of US Patent 5,284,662?
The main innovation is an oral osmotic system designed to deliver slightly soluble active agents in a controlled manner.
What are the key components of the system described in the patent?
The key components include a core containing the active agent, a semi-permeable wall, and a bore or orifice.
How does the system achieve controlled release?
The system achieves controlled release by allowing water to enter the core through the semi-permeable wall, which pushes the active agent out through the bore.
What are some potential challenges in implementing this system?
Challenges include formulation difficulties and the complexity of the manufacturing process.
How does this patent impact the pharmaceutical industry?
It provides a reliable method for delivering slightly soluble drugs, enhancing patient compliance and reducing side effects.
Cited Sources:
- United States Patent 5,393,765 - Pharmaceutical compositions with constant erosion volume for zero order controlled release[1].
- United States Patent 20030219485A1 - Oral osmotic controlled drug delivery system[2].
- United States Patent 5,284,662 - Oral osmotic system for slightly soluble active agents[4].
- Google Patents: US5284662A - Oral osmotic system for slightly soluble active agents[4].
