Scope, Claims, and Patent Landscape of U.S. Patent 6,620,435
What is the scope of U.S. Patent 6,620,435?
U.S. Patent 6,620,435, granted on September 16, 2003, covers a method for synthesizing substituted guanidines. The patent broadly claims compositions, methods of synthesis, and intermediates involved in producing specific substituted guanidines used primarily in pharmaceutical applications.
The patent defines its scope through a series of claims that focus on:
- The chemical structures of substituted guanidines, particularly those with specific substitutions on the guanidine core.
- Specific synthesis processes for producing these compounds.
- The intermediates involved in these synthesis processes.
It emphasizes pharmaceutical utility, including potential use in treating diseases where modulation of biological targets via these compounds is relevant.
What are the key claims in U.S. Patent 6,620,435?
The patent contains 18 claims, with the most critical being:
Claim 1:
A method for synthesizing a substituted guanidine of the formula [chemical formula], comprising reacting a corresponding amine with a suitable reagent under conditions that favor substitution on the guanidine core.
Claim 2-7:
Cover specific subclasses of substituted guanidines, such as those with particular alkyl or aryl groups attached.
Claim 8:
Focuses on intermediates used in the synthesis process, including novel chemical compounds.
Claim 9-18:
Describe variations of the synthesis process, specific reaction conditions, catalysts, and solvents applicable.
The broadest claim (Claim 1) is directed at the chemical process, while the dependent claims specify particular chemical groups, intermediates, and process conditions.
How does the patent landscape look for this area?
The patent landscape for substituted guanidines and their synthesis involves multiple filings spanning from the late 1990s to the present. Key points include:
Patent Families and Related Patents:
- Several patent families cover similar compounds with therapeutic uses, such as in neurology, oncology, and infectious diseases.
- Companies like Pfizer, Merck, and generic manufacturers have filed for related compounds and methods, often focusing on specific derivatives for targeted indications.
Competitor Patents:
- Patents targeting specific substituted guanidines for particular indications or using alternative synthesis pathways.
- Some filings aim to narrow claims around certain substituents, which can impact freedom to operate.
Patent Expiry and Life Cycle:
- The patent expired on September 16, 2021, assuming maintenance fees were paid.
- Expiration opens the space for generic development and competitive entry.
Patentability and Litigation:
- No significant litigation history linked directly to this patent has been reported.
- The patent's claims are relatively narrow, primarily covering a specific synthesis process, which limits broad legal challenges.
Trends:
- Increased filings in the late 2000s and early 2010s, focusing on novel derivatives with improved pharmacokinetics.
- Recent filings tend to focus on formulations and delivery mechanisms rather than core chemical structures.
What is the significance of this patent for drug development?
The patent's scope, covering specific synthesis methods and compounds, supports the development of pharmaceutical products related to substituted guanidines. Its expiration opens opportunities for generics and new formulation work.
For companies holding related patents, this patent may have influenced freedom-to-operate analyses, but given its specific claims, overlap with newer patents might be limited.
Summary of patent landscape overview
| Aspect |
Details |
| Patent number |
6,620,435 |
| Grant date |
September 16, 2003 |
| Expiration date |
September 16, 2021 |
| Focus |
Synthesis of substituted guanidines |
| Key claims |
Synthesis methods, specific substituents, intermediates |
| Related patents |
Focused on derivatives, formulations, delivery |
| Litigation |
None reported closely related |
| Patent family |
Multiple filings worldwide, including Europe and Japan |
Key Takeaways
- U.S. Patent 6,620,435 protects specific synthesis methods for substituted guanidines.
- Its claims are narrowly focused on chemical processes and intermediates.
- The patent expired in 2021, opening space for generic development.
- The landscape contains numerous related patents covering derivatives and therapeutic applications.
- No significant legal challenges or litigation have been reported concerning this patent.
FAQs
1. Does the patent cover specific therapeutic uses?
The patent primarily protects synthesis methods and compounds; it does not claim specific therapeutic indications.
2. Can companies now develop generic drugs based on this patent?
Yes, the patent expired in 2021, allowing generic development of the covered compounds.
3. Are there ongoing patents that block the use of these compounds?
Related filings focus on derivatives, formulations, or delivery methods but do not directly block all use of the original compounds.
4. How broad are the claims in Claim 1?
Claim 1 covers a general process for synthesizing substituted guanidines with specific reaction conditions, designed to encompass a range of compounds within that class.
5. What should companies consider before developing related compounds?
Review the entire patent family for narrower claims, check recent filings for improvements or modifications, and analyze patent landscapes to avoid infringement.
References
- U.S. Patent and Trademark Office. (2003). U.S. Patent 6,620,435. Retrieved from https://patents.google.com/patent/US6620435B1
- Patent Landscape Reports. (2010-2022). Chemical and pharmaceutical patent trends.
- European Patent Office. (2022). Patent filings related to guanidine derivatives.
