Detailed Analysis of the Scope and Claims of United States Patent 5,212,176
Introduction
United States Patent 5,212,176, titled "R(+)-terazosin," is a significant patent in the pharmaceutical domain, particularly focusing on the enantiomer of the drug terazosin. This patent, issued on May 18, 1993, provides insights into the synthesis, composition, and therapeutic applications of the R(+)-enantiomer of terazosin.
Background of Terazosin
Terazosin is a well-known medication used primarily for the treatment of hypertension and benign prostatic hyperplasia (BPH). It belongs to the class of alpha-1 adrenergic blockers, which work by relaxing the muscles in the prostate and the opening of the bladder, making it easier to urinate[4].
Scope of the Patent
Enantiomer Focus
The patent specifically deals with the R(+)-enantiomer of terazosin. Enantiomers are non-superimposable mirror images of each other, and in the case of terazosin, the R(+)-enantiomer is one of the two enantiomers that make up the racemic mixture of the drug. This focus is crucial because enantiomers can have different pharmacological activities and side effect profiles[4].
Pharmaceutical Compositions
The patent claims pharmaceutical compositions containing the R(+)-enantiomer of terazosin. These compositions can include various salts, such as the hydrochloride, hydrobromide, sulfate, and others, which are commonly used to enhance the stability and bioavailability of the drug[4].
Claims of the Patent
Synthesis Methods
The patent describes methods for synthesizing the R(+)-enantiomer of terazosin. These methods involve specific chemical reactions and purification steps to obtain the desired enantiomer in high purity[4].
Therapeutic Uses
The patent claims the use of the R(+)-enantiomer of terazosin for treating various conditions, including:
- Hypertension: The R(+)-enantiomer is effective in lowering blood pressure by relaxing the smooth muscles in blood vessels.
- Hyperinsulinemia: It is also claimed to be useful in treating conditions associated with high insulin levels.
- Congestive Heart Failure: The enantiomer may be beneficial in managing heart failure by reducing the workload on the heart.
- Benign Prostatic Hyperplasia (BPH): Similar to the racemic mixture, the R(+)-enantiomer helps in relieving symptoms of BPH by relaxing the muscles in the prostate and bladder neck[4].
Patent Landscape
Related Patents
Several other patents are related to terazosin and its various forms:
- U.S. Pat. No. 4,112,097: This patent discloses and claims pharmaceutical compositions containing terazosin and its therapeutic use for treating hypertension[4].
- U.S. Pat. No. 4,251,532: This patent covers the dihydrate crystalline form of the hydrochloride salt of terazosin, marketed under the trade name Hytrin®[2].
- U.S. Pat. No. 5,294,615: This patent describes a non-solvated crystalline polymorph of terazosin hydrochloride, distinct from the Form I described in other patents[1].
Patent Scope Metrics
The scope of a patent can be measured using metrics such as independent claim length and independent claim count. These metrics help in assessing the breadth and clarity of the patent claims. For U.S. Patent 5,212,176, the claims are specific and detailed, indicating a well-defined scope that avoids overly broad claims[3].
Significance and Impact
Therapeutic Advantages
The R(+)-enantiomer of terazosin may offer therapeutic advantages over the racemic mixture, such as improved efficacy or reduced side effects. This is because enantiomers can have different affinities for receptor sites, which can influence their pharmacological activity[4].
Market and Clinical Implications
The patent's focus on a specific enantiomer opens up possibilities for developing new drugs or formulations with enhanced therapeutic profiles. This can lead to better treatment options for patients and potentially expand the market for terazosin-based medications.
Conclusion
United States Patent 5,212,176 is a comprehensive patent that delves into the specifics of the R(+)-enantiomer of terazosin, including its synthesis, pharmaceutical compositions, and therapeutic applications. The patent's detailed claims and the broader patent landscape highlight the importance of this enantiomer in the pharmaceutical industry.
Key Takeaways
- The patent focuses on the R(+)-enantiomer of terazosin.
- It includes methods for synthesizing and purifying the enantiomer.
- The R(+)-enantiomer is claimed for treating hypertension, hyperinsulinemia, congestive heart failure, and BPH.
- The patent is part of a larger landscape of terazosin-related patents.
- The scope of the patent is well-defined, avoiding overly broad claims.
FAQs
What is the main subject of U.S. Patent 5,212,176?
The main subject of U.S. Patent 5,212,176 is the R(+)-enantiomer of terazosin, including its synthesis, pharmaceutical compositions, and therapeutic uses.
What are the therapeutic uses claimed in the patent?
The patent claims the use of the R(+)-enantiomer of terazosin for treating hypertension, hyperinsulinemia, congestive heart failure, and benign prostatic hyperplasia (BPH).
How does the R(+)-enantiomer differ from the racemic mixture of terazosin?
The R(+)-enantiomer is one of the two non-superimposable mirror images that make up the racemic mixture of terazosin. It may have different pharmacological activities and side effect profiles compared to the racemic mixture.
What other patents are related to U.S. Patent 5,212,176?
Related patents include U.S. Pat. No. 4,112,097, U.S. Pat. No. 4,251,532, and U.S. Pat. No. 5,294,615, which cover different aspects of terazosin and its salts.
Why is the focus on a specific enantiomer important?
The focus on a specific enantiomer is important because it can lead to drugs with improved efficacy or reduced side effects, as enantiomers can have different affinities for receptor sites.
Cited Sources:
- US5412095A - Terazosin monohydrochloride and processes and intermediate for its production - Google Patents
- US Patent for R(+)-terazosin Patent (Patent # 5,212,176 issued May 18, 1993) - Justia Patents
- Patent Claims and Patent Scope - Hoover Institution
- US5212176A - R(+)-terazosin - Google Patents
- EP0708104B1 - Process and intermediate for the ... - Google Patents
