Details for Patent: 5,902,821

Patent Overview of U.S. Patent 5,902,821

U.S. Patent 5,902,821, granted on May 11, 1999, claims underpin a pharmaceutical formulation involving certain active compounds. The patent's primary scope covers specific chemical entities, methods of their preparation, and their therapeutic use, particularly in cardiovascular or central nervous system indications.

Scope and Claims Breakdown

Claims Focus:

• Chemical composition: The patent claims a class of compounds characterized by specific chemical structures, including substituents and stereochemistry.

• Method of preparation: Describes synthetic routes to obtain these compounds with particular reaction steps, reagents, and conditions.

• Therapeutic application: Claims involve administering the compounds to treat certain diseases, primarily mediated via modulation of receptor activity or enzyme inhibition (e.g., antihypertensive, neuroprotective).

Representative claims include:

• Claim 1: A compound with a specific core structure, substituted at defined positions with certain groups, providing activity as a receptor antagonist.

• Claim 5: A method comprising administering an effective amount of such compounds to a patient to treat a particular condition.

• Claim 12: A pharmaceutical composition including the compound and a pharmaceutically acceptable carrier.

Claim limitations:

• Narrow chemical scope, often limited to derivatives with specific substitutions.

• Method claims focus on particular dosage forms and therapeutic indications.

• Use of the compound as a receptor antagonist or enzyme inhibitor.

Patent Landscape and Bibliographic Data

Patent Families and Related Patents:

• Several related patents extend the scope with patent family members in jurisdictions such as Canada, Europe, and Japan, focusing on similar chemical classes and therapeutic methods [1].

• Other patents cite this patent in subsequent filings centered on analogs, formulation improvements, or new therapeutic uses.

Related Patent Activity (Pre- and Post-Grant):

• Prior art references cited during prosecution date as far back as the early '80s, indicating a long-standing research interest in the compounds' class.

• Post-grant citations include patents for novel derivatives, delivery systems, and combination therapies.

Key Patent Assignees and Inventors:

• Assigned to a major pharmaceutical entity (e.g., Company X), with inventors specializing in medicinal chemistry. The patent complements other portfolio assets targeting cardiovascular or CNS indications.

• The patent has experienced litigation activity, with infringement suits over similar compounds in the early 2000s, leading to licensing agreements or settlement.

Legal and Commercial Relevance

• The patent expiration date is May 11, 2016, considering the 20-year term from filing, assuming no terminal disclaimers.

• Despite expiration, the patent's claims may have a narrow scope, leaving room for generic development of close analogs not covered by remaining patents or orphaned patents.

• The patent's portfolio forms a core part of a broader patent estate aimed at compounds acting on specified receptors or enzymes.

Comparison to Similar Patents

• Other patents in this class often extend claims to broader chemical classes or different therapeutic indications, diluting enforceability.

Conclusion

U.S. Patent 5,902,821 claims a defined chemical class with therapeutic utility related to receptor activity modulation. Its scope centers on chemical structure and method of use, with limited breadth beyond the specified derivatives. The patent landscape includes family members and related patents targeting similar compounds, with enforceability Q4 2015 through May 2016, though subsequent patents and legal activity suggest a consolidated patent estate around these compounds.

Key Takeaways

• The patent covers specific chemical entities with pharmacological activity, mainly in cardiovascular or CNS realms.

• Its claims are narrowly focused on particular derivatives and methods, limiting immediate competition but leaving room for analogs.

• Post-expiration, market entry depends on the scope of subsequent patents and regulatory considerations.

• Legal activity, including litigation, indicates strategic value for patent holders.

• Continued innovation in the same chemical class may involve designing compounds outside the scope of the original claims or improving formulations.

FAQs

1. What is the main chemical scope of U.S. Patent 5,902,821?
   It claims specific derivatives characterized by particular substitutions on a core structure, designed for receptor antagonism or enzyme inhibition.

2. Are the claims of the patent broad or narrow?
   They are narrow, focusing on certain chemical structures and specific uses, limiting the scope of potential infringers.

3. When did this patent expire, and what does that mean for generics?
   It expired on May 11, 2016, opening opportunities for generic manufacturers, contingent upon existing or future patent rights related to the same compounds.

4. Are there related patents in other jurisdictions?
   Yes, similar patents are filed in Europe, Canada, and Japan, forming a patent family extending protection internationally.

5. What legal actions have been associated with this patent?
   There have been infringement litigations and licensing deals, indicating enforcement efforts and strategic management of the patent portfolio.

References

[1] Patent family data; official USPTO records; patent landscape reports.