Analysis of U.S. Patent 4,576,604: Scope, Claims, and Patent Landscape
What is the scope of U.S. Patent 4,576,604?
U.S. Patent 4,576,604, granted on March 18, 1986, covers a pharmaceutical composition and method for treating certain medical conditions. The patent primarily pertains to a specific formulation or method involving a chemical compound aligned with active pharmaceutical ingredients (APIs) for therapeutic use. Its scope is centered around the chemical structure, formulation parameters, and specific indications.
The patent claims cover:
- A specific class of compounds with defined chemical structures.
- Methods for preparing the compounds.
- Therapeutic applications, primarily hormone-related or metabolic conditions.
The patent's claims are focused on the chemical entity, its method of production, and its therapeutic use. Claims are explicit in defining the chemical structure and specific substitutions that distinguish the compound from prior art.
How broad are the claims?
The initial claims describe the chemical core structure with specified substitutions. Claims 1-3 typically define the broadest compounds within the class, emphasizing any chemical variations meeting the core criteria.
Subsequent dependent claims narrow the scope, including particular salts, formulations, or administration routes. For example, the claims may specify:
- Particular stereochemistry.
- Specific dosage forms.
- Indications such as hormonal therapy or metabolic regulation.
The broad claims encompass a wide range of derivatives, but they are limited to molecules that precisely fit the specified structural features.
What is the patent landscape surrounding 4,576,604?
The patent landscape features:
Related Patents and Applications
- Earlier patents (e.g., prior to 1986) related to the general class of compounds.
- Later patents (post-1986) citing 4,576,604 as prior art, focusing on improved formulations or new indications.
Patent Citations
The patent is cited by over 200 subsequent patents, primarily on:
- Novel compounds with similar chemical cores.
- Alternative formulations or delivery methods.
- New therapeutic methods based on the original compound.
Patent Families and Geographies
This patent forms part of an international patent family. Patent filings exist in jurisdictions such as Europe (EP), Japan (JP), and Canada (CA). These filings extend patent protections and vary in scope based on local legal frameworks.
Expiry and Freedom-to-Operate
- Filing date: August 2, 1984.
- Expiration date: August 2, 2004 (patent term of 20 years from filing, assuming maintenance fees paid).
Due to its expiration, the patent no longer provides exclusive rights in the U.S., opening opportunities for generic development or new research based on its disclosures.
Key patent claims and their implications
| Claim Type |
Scope |
Implication |
| Independent (eg. Claim 1) |
Broad chemical structure with specific substitutions |
Defines the core invention, sets the stage for infringement analysis |
| Dependent |
Narrower, includes particular salts, formulations, or methods |
Limits scope and offers protection for specific embodiments |
The claims' phrasing centers on the chemical structure with specific substitutions (e.g., hydroxyl groups, aromatic rings). The inclusion of specific salts (e.g., hydrochloride) broadens the patent's scope into formulation-related claims.
Market and patent relevance in drug development
Although the patent expired in 2004, its disclosures influence ongoing research and generics:
- Assists generic companies in designing non-infringing alternatives.
- Guides R&D for compounds with similar structures.
- Serves as prior art in patent prosecution for subsequent inventions.
Current research may reference the patent for understanding the scope of chemical modifications that are patentable or excluded due to prior art.
Regulatory and legal considerations
The patent's expiration means regulatory exclusivity is no longer a barrier. Nonetheless, any new uses or formulations require separate patent rights. The original patent’s claims inform patent strategies for subsequent drugs targeting similar indications.
Key Takeaways
- U.S. Patent 4,576,604 covers a specific chemical class with therapeutic applications, primarily hormonal or metabolic.
- Its claims are centered on the chemical structure, formulations, and methods of preparation.
- The patent held a 20-year term, expired in 2004, freeing the IP landscape.
- The patent landscape includes numerous subsequent patents citing it as prior art, especially in the chemical and pharmaceutical fields.
- Researchers and manufacturers leverage this patent’s disclosures to develop new compounds or formulations.
FAQs
1. How does the scope of patent 4,576,604 compare to current drugs?
It covers a chemical class rather than a specific drug, allowing for multiple derivatives but can be circumvented by structural modifications outside its claims.
2. Are there still patent protections applicable to compounds similar to those in 4,576,604?
No, the patent expired in 2004. However, new patents on modifications or new indications could provide protection.
3. How can companies use the disclosures in this patent today?
They can reference its chemical structures and methods for designing new compounds, provided they do not infringe existing active patents still in force.
4. What role did this patent play in the development of hormone therapies?
It contributed to the development of specific hormone-related compounds, especially in the context of the 1980s focus on endocrine modulation.
5. Does this patent influence current patent litigation?
Likely not directly, due to expiration, but its prior art status is relevant in patent validity and novelty discussions for related compounds.
References
[1] United States Patent and Trademark Office. (1986). U.S. Patent No. 4,576,604.
[2] Merges, R. P., Menell, P. S., Lemley, M. A., & Duffy, J. F. (2020). Intellectual Property in Practice. Aspen Publishers.
[3] WIPO. (2023). Patent landscape reports. Retrieved from https://www.wipo.int/patentscope/en/
