Analyzing the Scope and Claims of United States Patent 6,224,905
Introduction
United States Patent 6,224,905, titled "Biconvex rapidly disintegrating dosage forms," is a patent that describes a process for preparing solid, rapidly disintegrating dosage forms with symmetrical convex top and bottom surfaces. Here, we will delve into the details of the patent's scope, claims, and the broader patent landscape.
Patent Overview
The patent, filed as US09/194,808, was granted on May 1, 2001. It pertains to the pharmaceutical industry, specifically to the formulation and manufacturing of solid dosage forms that disintegrate rapidly in water.
Claims
The patent includes several claims that define the scope of the invention:
Independent Claims
- Claim 1: This claim describes the process of preparing solid rapidly disintegrating dosage forms with symmetrical convex top and bottom surfaces. It involves dissolving or dispersing matrix-forming agents in a first solvent, freezing the mixture, and then contacting it with a second solvent to remove the first solvent, resulting in a solid matrix substantially free of the first solvent[4].
Dependent Claims
- Claims 2-10: These claims further specify the process and the resulting dosage forms. For example, Claim 2 specifies the use of water as the first solvent and ethanol as the second solvent. Other claims detail the volume of the mold, the disintegration time of the dosage form, and the materials used in the process[4].
Scope of the Invention
The scope of the invention is defined by the claims and the detailed description provided in the patent.
Symmetrical Convex Dosage Forms
The patent introduces a method to create dosage forms with symmetrical convex top and bottom surfaces. This symmetry eliminates the need to orient the dosage forms before packaging, reducing the complexity and cost of the manufacturing process[4].
Materials and Process
The process involves using a first solvent (typically water) to dissolve or disperse matrix-forming agents, which are then frozen and contacted with a second solvent (such as ethanol) to remove the first solvent. This results in a solid matrix that is substantially free of the first solvent[4].
Advantages
- Reduced Friability: The symmetrical convex shape reduces the acute angles between the side walls and the top or bottom surfaces, making the dosage forms less friable.
- Ease of Packaging: The symmetry eliminates the need for orientation steps, simplifying the packaging process.
- Rapid Disintegration: The dosage forms are designed to disintegrate rapidly in water, which is a critical feature for certain pharmaceutical applications[4].
Patent Landscape
Prior Art
The patent references prior art, such as GB-A-1,548,022 and U.S. Pat. No. 4,305,502, which describe solid rapidly disintegrating dosage forms but with distinct top and bottom surfaces. The current invention improves upon these by introducing symmetrical convex surfaces[4].
International Patent Databases
To understand the global patent landscape, one would need to search international patent databases such as those provided by the European Patent Office (EPO), Japan Patent Office (JPO), World Intellectual Property Organization (WIPO), and others. These databases can reveal similar or related patents filed in other jurisdictions[1].
Common Citation Document (CCD)
Using tools like the Common Citation Document (CCD), one can consolidate prior art citations from multiple patent offices to see if similar inventions have been patented elsewhere. This helps in understanding the global scope and potential overlaps or differences[1].
Examination and Maintenance
Patent Examination Process
Research indicates that the patent examination process can significantly narrow the scope of patent claims. Studies have shown that narrower claims at publication are associated with a higher probability of grant and a shorter examination process[3].
Patent Maintenance
The maintenance of a patent involves periodic payments to keep the patent in force. The scope and claims of a patent can influence these maintenance payments, with narrower, more focused claims potentially reducing these costs[3].
Practical Applications and Examples
The patent provides several examples of how the process can be applied to different active ingredients, illustrating its versatility. For instance, the examples include pharmaceuticals, but the method is applicable to many other types of active ingredients[4].
Key Takeaways
- Symmetrical Convex Dosage Forms: The patent introduces a method to create dosage forms with symmetrical convex top and bottom surfaces, reducing friability and simplifying packaging.
- Materials and Process: The process involves using a first and second solvent to create a solid matrix substantially free of the first solvent.
- Advantages: Reduced friability, ease of packaging, and rapid disintegration in water.
- Prior Art: Improves upon previous dosage forms with distinct top and bottom surfaces.
- Global Patent Landscape: Searching international databases and using tools like CCD can reveal similar or related patents.
FAQs
Q: What is the main innovation of United States Patent 6,224,905?
A: The main innovation is the creation of solid rapidly disintegrating dosage forms with symmetrical convex top and bottom surfaces, which simplifies the manufacturing and packaging process.
Q: How does the process described in the patent reduce friability?
A: The symmetrical convex shape reduces the acute angles between the side walls and the top or bottom surfaces, making the dosage forms less friable.
Q: What are the typical solvents used in the process?
A: Water is typically used as the first solvent, and ethanol is used as the second solvent.
Q: How does the patent improve upon prior art?
A: It eliminates the need for orientation steps in packaging by introducing symmetrical convex surfaces, unlike previous dosage forms with distinct top and bottom surfaces.
Q: What tools can be used to understand the global patent landscape related to this invention?
A: Tools like the Common Citation Document (CCD) and international patent databases such as those provided by the EPO, JPO, and WIPO can be used.
Sources
- USPTO: Search for patents - USPTO
- ACUS: U.S. Patent Small Claims Court
- SSRN: Patent Claims and Patent Scope
- Google Patents: US6224905B1 - Biconvex rapidly disintegrating dosage forms
- Unified Patents Portal: US-9498432-B2 - Unified Patents Portal
