United States Patent 5,087,454: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 5,087,454, titled "Ibuprofen Tablet," was issued on February 11, 1992. This patent is significant in the pharmaceutical industry, particularly in the formulation and manufacturing of ibuprofen tablets. Here, we will delve into the scope, claims, and the broader patent landscape surrounding this invention.
Background of the Invention
The patent addresses the challenges associated with the dissolution characteristics of ibuprofen in compressed tablets. Ibuprofen, a non-steroidal anti-inflammatory drug (NSAID), has unique properties that can affect its dissolution profile, which is crucial for its efficacy and stability over time[1].
Scope of the Invention
The invention focuses on improving the stability of the dissolution profile of ibuprofen tablets over a period of up to two years. This is achieved through a specific formulation and manufacturing process involving wet granulation of ibuprofen with a binder, such as starch, followed by the addition of lubricants and disintegrating agents before compression into tablets[1].
Key Components
- Wet Granulation: The process involves wet granulation of ibuprofen to create a stable base granulation for the compression mix.
- Binders and Excipients: The use of binders like starch, disintegrants such as croscarmellose sodium, and lubricants to enhance tablet stability and dissolution.
- Dissolution Profile: The tablets are designed to maintain a stable dissolution profile, meeting the USP (United States Pharmacopeia) standards for dissolution times[1].
Claims of the Patent
The patent includes several claims that define the scope of the invention:
Independent Claims
- The invention claims improved ibuprofen tablets/caplets with a stable dissolution profile maintained for up to two years.
- The tablets are formed by wet granulation of ibuprofen with a binder, followed by drying, mixing with lubricants and disintegrating agents, and compression into tablets[1].
Dependent Claims
- Specific formulations and methods of preparing the tablets, including the use of particular excipients and the process of sugar coating and polishing the tablets.
- Comparative examples showing the improved dissolution characteristics of the invented tablets versus prior art methods[1].
Patent Landscape
Prior Art
The patent references several prior art patents, notably U.S. Pat. No. 4,904,477, which describes spray-dried ibuprofen compositions. However, the current invention improves upon these by providing a more stable dissolution profile through a different formulation and manufacturing process[1].
Related Patents
Other patents in the same field, such as U.S. Pat. No. 6,599,531, focus on different aspects of pharmaceutical compositions, including the combination of ibuprofen with narcotic analgesics. These patents highlight the ongoing research and development in optimizing pharmaceutical formulations[4].
Impact on the Pharmaceutical Industry
Stability and Efficacy
The invention's focus on maintaining a stable dissolution profile ensures that the ibuprofen tablets remain effective over their shelf life, which is crucial for patient safety and treatment efficacy.
Manufacturing Process
The wet granulation process and the specific formulation described in the patent provide a reliable method for manufacturing ibuprofen tablets, which can be adopted by pharmaceutical companies to improve their products.
Legal and Regulatory Aspects
Patent Expiration
The patent has expired, which means that the technology and methods described are now in the public domain. This allows other companies to use and build upon this invention without needing to obtain a license[1].
Litigation and Infringement
While the patent is expired, historical litigation and claim construction related to this patent can still provide valuable insights into how similar patents might be interpreted in legal disputes[5].
Metrics for Patent Scope
Claim Length and Count
Studies on patent scope, such as those by Marco, Alan C., and Sarnoff, Joshua D., suggest that the length and count of independent claims can be metrics for measuring patent scope. In this case, the patent's claims are specific and focused, indicating a well-defined scope[3].
Conclusion
United States Patent 5,087,454 represents a significant advancement in the formulation and manufacturing of ibuprofen tablets. Its focus on maintaining a stable dissolution profile over time has contributed to the development of more reliable and effective NSAID treatments.
Key Takeaways
- Improved Dissolution Profile: The patent describes a method to maintain a stable dissolution profile for ibuprofen tablets over two years.
- Wet Granulation Process: The use of wet granulation with specific binders and excipients is key to the invention.
- Regulatory Compliance: The tablets meet USP standards for dissolution times.
- Public Domain: The patent has expired, making the technology publicly available.
- Industry Impact: The invention has influenced the manufacturing process and efficacy of ibuprofen tablets.
FAQs
What is the main improvement of the ibuprofen tablets described in U.S. Patent 5,087,454?
The main improvement is the stable dissolution profile maintained for up to two years, ensuring consistent efficacy over the shelf life of the tablets.
How are the ibuprofen tablets in this patent manufactured?
The tablets are manufactured through a wet granulation process involving ibuprofen, a binder like starch, lubricants, and disintegrating agents, followed by compression into tablets.
What prior art does this patent reference?
The patent references U.S. Pat. No. 4,904,477, which describes spray-dried ibuprofen compositions.
Is the patent still in force?
No, the patent has expired, making the technology and methods described in the public domain.
How does this patent impact the pharmaceutical industry?
It provides a reliable method for manufacturing ibuprofen tablets with a stable dissolution profile, ensuring patient safety and treatment efficacy.
Sources
- US5087454A - Ibuprofen tablet - Google Patents
- Patent Claims Research Dataset - USPTO
- Patent Claims and Patent Scope - Search eLibrary :: SSRN
- US6599531.pdf - United States Patent
- Court Report - Patent Docs
