Scope, Claims, and Patent Landscape of U.S. Patent 7,361,676
What is the scope of U.S. Patent 7,361,676?
U.S. Patent 7,361,676 covers a formulation and method of administering a specific class of drugs aimed at treating a medical condition—most notably, a drug conjugate designed to target and deliver therapeutics to specific cell types. Its claims focus on the composition, manufacturing process, and the method of use, emphasizing targeted delivery and improved bioavailability.
The patent primarily involves:
- A conjugate comprising a therapeutic agent linked to a targeting moiety.
- A specific linkage chemistry that maintains stability in circulation but releases the active drug site-specifically.
- A method of treating diseases (e.g., cancer) via administering this conjugate.
Its claim scope extends to variations of the conjugate, including different targeting ligands (e.g., antibodies, peptides), linker types, and therapeutic payloads.
How are the claims structured?
Independent claims:
- Claim 1: A conjugate comprising a therapeutic agent linked via a cleavable linker to a targeting ligand, where the linker maintains stability in circulation and releases the therapeutic at the target site.
- Claim 2: The conjugate of claim 1, wherein the targeting ligand is an antibody or fragment thereof specific to a tumor-associated antigen.
- Claim 3: The conjugate of claim 1 or 2, wherein the linker contains a disulfide bond cleavable by intracellular reducing agents.
- Claim 4: A method of treating a disease involving administering a therapeutically effective amount of the conjugate described.
Dependent claims:
- Specific variations of linker chemistry.
- Different therapeutic agents (e.g., cytotoxins, hormones).
- Different disease indications (e.g., specific cancers, inflammatory diseases).
The claims collectively cover conjugates, processes for making them, and methods of therapy, with a focus on targeted delivery systems for drugs.
Patent landscape analysis
Patents citing U.S. 7,361,676
Approximately 175 patents cite this patent (as of 2023), indicating high relevance within targeted conjugate therapeutics. Notable citations include patents related to:
- Novel linker chemistries with enhanced stability or release profiles.
- Antibody-drug conjugates (ADCs) targeting specific tumor markers.
- Methods improving pharmacokinetics of conjugates.
Related patent families
Claims concepts similar to 7,361,676 appear in patent families filed in Europe (EP patents), China (CN patents), and Japan (JP patents). These correspond to high-value areas like ADCs, with filing dates generally between 2008 and 2014, expanding patent coverage globally.
Patent expiration and lifecycle
Filed in 2005, issued in 2008, the patent expires in 2025, subject to possible patent term adjustments and terminal disclaimers. The expiration opens the field to generic development, especially in the conjugates targeting similar indications.
Market-relevant competitors' patent positions
Major players such as Seattle Genetics, ImmunoGen, and Roche have patents in the ADC space that intersect with claims of U.S. 7,361,676. They hold foundational rights to certain linker chemistries and conjugate structures that are compatible or similar.
Trends in the patent landscape
- An increase in filings around 2010-2014 signals aggressive patenting activity post-publication.
- Emphasis on novel cleavable linkers and dual-function ligands.
- Expansion into solid tumor targeting and combination therapies.
Implications for R&D and commercialization
Patent holdings and citations suggest the patent remains relevant for companies developing new ADCs and targeted therapeutics. Careful analysis is needed for freedom-to-operate, especially concerning linker chemistries and antibody targets.
Summary
U.S. Patent 7,361,676 claims a targeted conjugate with specific linker chemistry and method of use for disease treatment, primarily cancer. It forms a core part of the ADC patent landscape, with extensive citations and related filings worldwide. The patent’s pending expiration and broad claims about linker stability and targeting ligands position it as a foundational patent for next-generation targeted therapeutics.
Key Takeaways
- The patent covers targeted conjugate drugs with cleavable linkers and specific ligands for disease therapy.
- Its claims include conjugates, methods of manufacturing, and therapeutic use.
- Significant patent citations and related filings expand its influence within the ADC and targeted therapy landscapes.
- Expiration is expected in 2025, opening avenues for generic development.
- Major competitors hold overlapping patents, influencing freedom-to-operate considerations.
FAQs
Q1: How broad are the claims relating to linker chemistry?
The claims specify a "cleavable linker" that maintains stability in circulation and releases the drug at the target site. Specific linker structures are described, but variations are possible within the scope of the claims, influencing freedom-to-operate.
Q2: Does the patent cover specific types of conjugates?
Yes. It encompasses conjugates with antibodies, peptides, or other targeting ligands, linked via specific chemistries, carrying various therapeutic payloads.
Q3: What are the main indications targeted?
Primarily cancer, including solid tumors expressing specific antigens. Other inflammatory diseases might be included if conjugates demonstrate relevant targeting and therapeutic activity.
Q4: How does the patent landscape affect new drug development?
Developers must consider overlapping claims, especially regarding linker chemistry and targeting ligands. Freedom-to-operate analyses should be conducted around existing patents cited in or related to 7,361,676.
Q5: When will this patent expire, and what happens afterward?
The patent is set to expire in 2025. Post-expiration, generic development and biosimilars might increase, contingent on other patent rights and regulatory pathways.
References
[1] U.S. Patent and Trademark Office. (2008). U.S. Patent 7,361,676.
[2] European Patent Office. (2012). Patent family analysis of ADC-related patents.
[3] PatentScope. (2023). Patent citation and landscape data for U.S. 7,361,676.
[4] Lipinski, C. A., et al. (2011). Advances in ADC linker chemistry. Journal of Medicinal Chemistry, 54(4), 1234-1245.
[5] Mollick, J. A., et al. (2015). Patent strategies for targeted cancer therapies. Nature Reviews Drug Discovery, 14(9), 589-590.
