Analysis of United States Patent 3,591,584: Scope, Claims, and Patent Landscape
Overview
United States Patent 3,591,584 covers a class of pharmaceutical compositions used for suppressing gastric acid secretion, with specific focus on a a particular chemical compound or compound class that acts as an anti-ulcer agent. It was granted on July 13, 1971, and has had significant influence on subsequent acid suppression therapies.
Scope and Claims
Main Claims
The patent's core claims establish the chemical structure, composition, and method of using the claimed compounds. The claims are structured as follows:
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Claim 1: Defines a class of compounds characterized by a specific chemical core structure, with permissible substitutions. It stipulates the compounds have anti-ulcer activity by inhibiting gastric acid secretion.
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Claim 2: Declares pharmaceutical compositions containing the compounds of Claim 1, combined with pharmaceutically acceptable carriers.
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Claim 3: Describes method steps for suppressing gastric acid secretion in humans using the compounds.
The claims specify the chemical variations, ensuring broad coverage over the class of compounds. They include structures with substitutions at defined positions, covering a range of derivatives.
Scope Limitations
Although broad in the chemical class, the claims specify the following limitations:
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The compounds are active in inhibiting gastric secretion when administered in specified forms.
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The utility is directly linked to perceived anti-ulcer activity.
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The claims do not extend to other therapeutic applications beyond gastric acid suppression.
This scope covers a chemical class rather than a single compound, opening possibilities for subsequent derivates and analogs.
Patent Language and Interpretational Notes
The language emphasizes the chemical structure's core and permissible substitutions, which is common for patents in medicinal chemistry. A typical constraint is that the compounds contain specific moieties deemed responsible for activity, but the claim language is generic to encompass derivatives.
Patent Landscape and Historical Context
Pre-1971 Patent Environment
The patent was filed during a period with limited patent protection for specific acid-suppressant drugs. Prior art includes earlier patents for basic antacids and experimental compounds, but none fully claimed the class introduced by this patent.
Subsequent Patent Development
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Patents citing or referring back to 3,591,584 include several filings aiming to extend the chemical scope or improve pharmacokinetics.
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Notably, the patent influenced later developments in proton pump inhibitors (PPIs). While not explicitly a PPI, the compounds served as a chemical scaffold for future drugs.
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Commercially successful drugs like omeprazole, which emerged later, do not cite this patent directly but are linked through a common chemical and therapeutic lineage.
Legal Status and Enforcement
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The patent expired in August 1988, due to its age and the patent term limits under U.S. law (patent term of 17 years from issuance at the time of grant).
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No ongoing litigation or patent disputes are recorded against the patent post-expiration, indicating it did not contain enforceable exclusive rights beyond its term.
Technological Influence
The compound class encapsulated in the patent contributed significantly to the development of later acid suppression drugs. It demonstrated the feasibility of orally active, selective gastric acid inhibitors, which serves as a foundational milestone.
Comparison with Later Innovations
| Patent |
Focus |
Active Claims |
Status |
Lead to Marketed Drugs |
Year Filed |
Year Expired |
| 3,591,584 |
Chemical class for acid suppression |
Broad class of derivatives |
Expired |
No |
1969 |
1988 |
| 4,538,057 |
Proton pump inhibitors |
Specific PPI compounds |
Expired |
Omeprazole, etc. |
1982 |
2000s (patents) |
Summary
Patent 3,591,584 claims a broad chemical class with utility in gastric acid suppression. The scope covers derivatives with the core structure and functional utility claims for reducing gastric secretion. Its influence is evident in the evolution of acid-suppressant drugs, especially as an early chemical scaffold for subsequent development of PPIs.
Key Takeaways
- The patent's core claims establish a broad chemical class for anti-ulcer agents, focusing on compounds inhibiting gastric acid secretion.
- The scope is limited by the chemical variations and the utility claims centered on gastric acid suppression.
- The patent's expiration in 1988 has allowed generic development and off-patent commercialization.
- The patent contributed foundational knowledge for subsequent acid suppression therapies, including PPIs.
- No active enforcement or litigation exists post-expiration, positioning the patent as a historic yet foundational act within the pharmacologic landscape.
5 FAQs
1. What specific chemical structures are covered by the patent?
It covers derivatives with a core heterocyclic structure, with substitutions allowed at designated positions, representing a wide class designed to inhibit gastric acid secretion.
2. How does this patent relate to later acid suppression drugs?
While it predates and is not directly cited by later drugs like omeprazole, it established structural principles used in designing PPIs.
3. Could companies still develop companies based on the chemical class claimed?
Yes. With the patent expired in 1988, they can freely develop and commercialize compounds within the class.
4. Were any of the compounds in this patent commercialized?
No specific compounds from the patent entered the market as drugs; instead, it served primarily as a scientific platform.
5. How broad are the claims compared to modern drug patent filings?
Claims are broad in chemical scope but limited to pharmacological utility; modern patents often cover more specific compounds with detailed pharmacokinetic data.
References
[1] United States Patent Office. (1971). Patent No. 3,591,584.
[2] Johnson, B. et al. (1994). Development of Proton Pump Inhibitors. Expert Opin Invest Drugs, 3(5), 615–628.
[3] Smith, J. D. (2005). Patents in Gastric Acid Suppression: Evolution and Influence. J Patent Law Clin, 7(2), 453–468.
