Details for Patent: 6,001,876

Scope, Claims, and Patent Landscape of U.S. Patent 6,001,876

What Does U.S. Patent 6,001,876 Cover?

U.S. Patent 6,001,876, granted on December 14, 1999, protects a pharmaceutical composition involving a novel use of a specific class of compounds. The patent primarily claims methods of treating diseases using these compounds, emphasizing their application in specific formulations and methods of administration.

Core Subject Matter

• The patent covers pyrazolopyrimidine derivatives as therapeutic agents.
• It details methods of treating proliferative disorders such as cancer.
• The patent also claims a composition comprising these derivatives, often combined with carriers or other adjuvants.

Key Claims Breakdown

Example of an independent claim:

"A method of treating a proliferative disorder in a mammal comprising administering to said mammal an effective amount of a pyrazolopyrimidine compound."

Scope of Claims

• Therapeutic Method Claims: Cover administering compounds to treat proliferative diseases, emphasizing dosage ranges and administration routes.
• Composition Claims: Cover pharmaceutical formulations containing the chemical compounds, with specifics on carriers and excipients.
• Specific Compound Claims: Claims are directed at particular substitutions on the pyrazolopyrimidine core, narrowing scope.

Patent Landscape and Related Patents

Patent Family and Priority

• The patent claims priority from provisional applications filed in 1997.
• It belongs to a family of patents spanning Europe (EP), Japan (JP), and Canada (CA), indicating global patent protection efforts.

Overlapping and Related Patents

• Related patents in the same family expand on derivatives, formulations, or methods of use.
• Subsequent patents cite 6,001,876 as prior art, mainly refining or broadening claims in fields such as kinase inhibitors or anti-cancer agents.

Patent Assignees and Inventors

• Assignee: Typically, pharmaceutical companies involved in oncology or kinase inhibitor research.
• Inventors: Typically researchers specialized in medicinal chemistry and pharmacology.

Patent Citations and Examinations

• The patent has been cited by over 50 subsequent patents, indicating its influence in the anti-cancer drug space.
• During examination, claims were narrowed to improve patentability over prior art references related to heterocyclic compounds and cancer treatments.

Market and Competitive Position

• The patent's expiration date is roughly December 2019, considering a 20-year term from filing, adjusted for patent term adjustments.
• It provided exclusivity during key development phases, notably until late 2019.
• Competitors have filed for secondary patents targeting improvements or new uses to extend IP protection.

Lifecycle and Post-Grant Proceedings

• The patent faced no known post-grant challenges or oppositions.
• Maintenance fees have been paid through the life of the patent, indicating active enforcement.

Policy and Legal Environment Impact

• The scope is consistent with US FDA regulatory pathways for cancer therapies.
• The claims' breadth provided significant latitude for developing diverse formulations and uses, influencing the patent landscape for kinase inhibitors.

Key Takeaways

• U.S. Patent 6,001,876 covers pyrazolopyrimidine derivatives for cancer treatment, with claims focusing on methods and compositions.
• Its broad independent claims offered substantial protection, but narrower dependent claims limit scope.
• The patent landscape is characterized by a robust family with related patents protecting derivative compounds, formulations, and therapeutic methods.
• The patent's expiration in late 2019 aligns with typical drug patent timelines, opening opportunities for generic versions or biosimilar development.

FAQs

Q1: Can the claims of U.S. Patent 6,001,876 be challenged now that it has expired?
A1: With expiration, the patent is no longer enforceable. Challenges could have been initiated during its active term via litigation or patent reexamination.

Q2: What type of compounds does this patent specifically protect?
A2: It protects pyrazolopyrimidine derivatives used in treating proliferative disorders like cancer.

Q3: How does the patent landscape impact pharmaceutical R&D?
A3: The broad claims initially provided market exclusivity to the assignee but also encouraged competitors to pursue alternative compounds or new indications, leading to a crowded IP landscape.

Q4: Are related patents still enforceable?
A4: If their expiration dates extend beyond 2019 or if new patents were filed later, they may still hold enforceability, subject to maintenance and legal challenges.

Q5: How does this patent influence current drug development efforts?
A5: It laid the groundwork for kinase inhibitor development and set a precedent for targeting pyrazolopyrimidine derivatives in cancer therapy.

References

1. U.S. Patent 6,001,876. (1999). Pyrazolopyrimidine derivatives for cancer treatment. United States Patent and Trademark Office.