United States Patent 4,810,502: A Detailed Analysis of Scope and Claims
Introduction
The United States Patent 4,810,502, filed by Ayer et al., is a significant contribution to the field of pharmaceutical formulations, particularly in the realm of osmotic dosage forms. This patent describes innovative designs for delivering single or combination active drugs in a controlled and efficient manner.
Background
Osmotic dosage forms have been a focus of pharmaceutical research due to their ability to provide consistent and controlled drug release over an extended period. This technology is crucial for maintaining therapeutic drug levels in the body, enhancing patient compliance, and reducing side effects associated with traditional dosing methods.
Scope of the Patent
Osmotic Dosage Form Design
The patent outlines an osmotic dosage form that consists of a core surrounded by a semipermeable membrane. This design is pivotal in controlling the release of the drug(s) contained within the core[4].
Core Composition
The core can contain either a single drug or a combination of active drugs. This flexibility allows for tailored therapeutic approaches, addressing various medical conditions with precision[4].
Semipermeable Membrane
The semipermeable membrane is a critical component, as it regulates the influx of water into the core and the subsequent release of the drug. The membrane can have one or more passageways (holes) that facilitate the controlled release of the drug[1][4].
Claims of the Patent
Bi-Layered Core
One of the key claims is the use of a bi-layered core, where the first layer contains a drug that is released rapidly over a short period (typically 2 minutes to 2 hours), and the second layer contains a drug that is released at a controlled rate over a longer period. This dual-release mechanism allows for both immediate and sustained therapeutic effects[1].
No Partition Between Layers
The layers of the core are in intimate contact without any separating layer, lamina, or membrane. This design ensures that each layer releases its drug through its respective hole in the semipermeable membrane[1].
Multiple Holes in the Membrane
The semipermeable membrane can have multiple holes, each corresponding to a different layer of the core. This allows for the independent release of drugs from each layer, providing a tailored release profile[1].
Comparison with Prior Art
Single-Layered Cores
Previous patents, such as U.S. Pat. No. 4,662,880 to Hamel et al., described single-layered cores surrounded by a semipermeable membrane with two oppositely placed holes. However, these designs did not include multiple drug-containing layers, which is a novel aspect of the 4,810,502 patent[1].
Multi-Layered Tablets
Other patents, like U.S. Pat. No. 8685451B2, describe multi-layered tablets with different release profiles, but these do not involve the use of a semipermeable membrane with multiple holes for controlled release[2].
Advantages and Innovations
Controlled Release
The design allows for precise control over the release of drugs, which is crucial for maintaining therapeutic levels and minimizing side effects. This controlled release profile can enhance patient compliance and treatment efficacy[1][4].
Combination Therapy
The ability to include multiple drugs in a single dosage form facilitates combination therapy, which can be more effective than monotherapy in many cases. This is particularly beneficial for treating complex diseases that require multiple therapeutic agents[1].
Improved Toxicity Profile
By releasing drugs in a controlled manner, the patent suggests that the pharmaceutical composition can have an improved toxicity profile compared to administering each drug separately. This reduces the risk of adverse effects and enhances the overall safety of the treatment[1].
Industrial and Clinical Implications
Manufacturing and Formulation
The patent provides detailed descriptions of how to manufacture these osmotic dosage forms, including the materials and processes involved. This makes it easier for pharmaceutical companies to develop and produce these formulations on a large scale[4].
Therapeutic Applications
The controlled release mechanism and the ability to combine multiple drugs make this technology applicable to a wide range of therapeutic areas, including but not limited to, cardiovascular diseases, diabetes, and neurological disorders[1].
Key Takeaways
- The patent describes an osmotic dosage form with a bi-layered core and a semipermeable membrane.
- Each layer of the core can release a different drug through separate holes in the membrane.
- The design allows for both immediate and sustained drug release.
- The technology is suitable for combination therapy and can improve the toxicity profile of the drugs.
- The patent provides detailed manufacturing and formulation guidelines.
Frequently Asked Questions (FAQs)
What is the main innovation of U.S. Patent 4,810,502?
The main innovation is the use of a bi-layered core within an osmotic dosage form, allowing for the controlled release of multiple drugs through separate holes in the semipermeable membrane.
How does the bi-layered core work?
The bi-layered core consists of two layers: one layer releases a drug rapidly, while the other layer releases a drug at a controlled rate over a longer period.
What are the advantages of this design?
The design provides precise control over drug release, enhances patient compliance, and can improve the toxicity profile by reducing side effects.
Can this technology be used for combination therapy?
Yes, the technology is well-suited for combination therapy, allowing multiple drugs to be delivered in a single dosage form.
What are the potential therapeutic applications of this technology?
The technology has potential applications in various therapeutic areas, including cardiovascular diseases, diabetes, and neurological disorders.
Cited Sources:
- US20030185882A1 - Pharmaceutical compositions containing oxybutynin - Google Patents.
- US8685451B2 - Triple combination release multi-layered tablet - Google Patents.
- Patent Claims and Patent Scope - SSRN.
- U.S. Pat. No. 4,810,502 to Ayer et al. - Justia Patents.
