United States Patent 5,731,000: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 5,731,000, titled "Stabilized pharmaceutical composition containing bupropion," is a significant patent in the pharmaceutical industry, particularly in the field of antidepressant medications. This patent, granted to Glaxo Wellcome Inc., introduces a method and composition for stabilizing bupropion hydrochloride, a commonly used antidepressant. Here, we will delve into the scope, claims, and the broader patent landscape surrounding this invention.
Background of the Invention
Bupropion hydrochloride is an antidepressant medication known for its efficacy in treating depression and other mental health conditions. However, one of the challenges associated with bupropion hydrochloride is its tendency to degrade over time, which can affect its potency and shelf life. The invention described in US Patent 5,731,000 addresses this issue by introducing a stabilizer to prevent the degradation of bupropion hydrochloride[4][5].
Scope of the Invention
The scope of this patent is focused on the stabilization of bupropion hydrochloride in pharmaceutical compositions. The invention includes:
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Pharmaceutical Compositions: The patent describes solid pharmaceutical compositions, such as tablets and capsules, that contain bupropion hydrochloride and a pharmaceutically acceptable stabilizer. These compositions are designed to maintain the potency of bupropion hydrochloride over a prolonged period[4][5].
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Stabilizers: The patent specifies the use of various stabilizers, including organic acids, carboxylic acids, acid salts of amino acids, and sodium metabisulphite. These stabilizers prevent the degradation of bupropion hydrochloride under different storage conditions[4].
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Storage Conditions: The compositions are tested under various storage conditions, including high temperatures and humidity, to ensure that they retain at least 80% of their labeled strength after one year of storage[4].
Claims of the Patent
The patent includes several claims that define the scope of the invention:
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Claim 1: This claim describes the pharmaceutical composition comprising bupropion hydrochloride and a pharmaceutically acceptable stabilizer in an effective stabilizing amount. The composition must contain at least about 80% w/w of undegraded bupropion hydrochloride after storage for 6 weeks at about 40°C and 75% relative humidity[4].
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Claim 2: This claim specifies the types of stabilizers that can be used, including organic acids and acid salts of amino acids[4].
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Claim 3: This claim describes the method of stabilizing bupropion hydrochloride by admixing it with the stabilizer, ensuring that the composition retains its potency over time[4].
Patent Landscape
Related Patents and Applications
The patent landscape surrounding US Patent 5,731,000 includes other patents related to the stabilization of pharmaceutical compositions and the use of bupropion hydrochloride.
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Global Patent Family: The patent is part of a global patent family, with corresponding patents filed in other jurisdictions. This indicates the international significance of the invention[4].
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Prior Art: The patent cites prior art related to pharmaceutical compositions and stabilizers, highlighting the novelty of the current invention in addressing the specific issue of bupropion hydrochloride degradation[4].
Industry Impact
The stabilization of bupropion hydrochloride has significant implications for the pharmaceutical industry:
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Improved Shelf Life: The invention ensures that bupropion hydrochloride retains its potency over a longer period, which is crucial for both manufacturers and consumers[4].
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Cost Efficiency: By preventing degradation, the invention reduces the need for frequent reformulation and re-manufacturing, thereby saving costs[4].
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Regulatory Compliance: The patent helps in meeting regulatory standards for pharmaceutical stability and potency, ensuring that the product remains safe and effective for use[4].
Search and Analysis Tools
For professionals conducting patent searches related to this area, several tools are available:
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Patent Public Search: The USPTO's Patent Public Search tool provides enhanced access to prior art and can be used to search for patents related to pharmaceutical compositions and stabilizers[1].
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Global Dossier: This service allows users to access the file histories of related applications from participating IP Offices, which can be useful in understanding the global patent landscape for similar inventions[1].
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Patent Examination Data System (PEDS): This system provides access to bibliographic data for all publicly available patent applications, which can be used to analyze trends and patterns in patent filings related to pharmaceuticals[1].
Metrics for Patent Scope
When analyzing the scope of patents like US 5,731,000, metrics such as independent claim length and independent claim count can be useful. These metrics help in understanding the breadth and clarity of the patent claims, which are crucial for assessing patent quality and potential litigation risks[3].
Conclusion
US Patent 5,731,000 is a pivotal invention in the field of pharmaceuticals, particularly for the stabilization of bupropion hydrochloride. The patent's scope and claims are carefully defined to ensure the efficacy and stability of the pharmaceutical composition. Understanding this patent and its place within the broader patent landscape is essential for researchers, manufacturers, and legal professionals in the pharmaceutical industry.
Key Takeaways
- Stabilization Method: The patent introduces a method to stabilize bupropion hydrochloride using various stabilizers.
- Pharmaceutical Compositions: The invention includes solid compositions like tablets and capsules.
- Storage Conditions: The compositions are designed to retain potency under various storage conditions.
- Industry Impact: The invention improves shelf life, cost efficiency, and regulatory compliance.
- Patent Landscape: The patent is part of a global family and has significant implications for the pharmaceutical industry.
FAQs
Q1: What is the main issue addressed by US Patent 5,731,000?
The main issue addressed is the degradation of bupropion hydrochloride, an antidepressant medication, over time.
Q2: What types of stabilizers are used in the patent?
The patent specifies the use of organic acids, carboxylic acids, acid salts of amino acids, and sodium metabisulphite as stabilizers.
Q3: How does the invention improve the shelf life of bupropion hydrochloride?
The invention ensures that the pharmaceutical composition retains at least 80% of its labeled strength after one year of storage under typical conditions.
Q4: What are the implications of this patent for the pharmaceutical industry?
The patent improves shelf life, reduces costs associated with frequent reformulation, and ensures regulatory compliance.
Q5: How can one search for related patents in this field?
One can use tools like the USPTO's Patent Public Search, Global Dossier, and the Patent Examination Data System (PEDS) to search for related patents.
Sources
- USPTO - Search for patents: https://www.uspto.gov/patents/search
- USPTO - Patent Claims Research Dataset: https://www.uspto.gov/ip-policy/economic-research/research-datasets/patent-claims-research-dataset
- SSRN - Patent Claims and Patent Scope: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2844964
- Google Patents - Stabilized pharmaceutical composition containing bupropion: https://patents.google.com/patent/US5731000A/en
- Justia Patents - Stabilized pharmaceutical composition containing bupropion: https://patents.justia.com/patent/5731000
