Scope and Claims Analysis of U.S. Patent 4,713,394
What does Patent 4,713,394 cover within its claims?
U.S. Patent 4,713,394, issued on December 15, 1987, to the University of Wisconsin, primarily covers a method of producing a particular class of therapeutic compounds—interferon-inducing agents derived from polycyclic compounds. The patent claims specific chemical structures, processes for preparation, and their use in stimulating immune response via interferon induction.
Patent Scope
The patent focuses on novel polycyclic compounds and their derivatives. Its scope includes:
- Specific chemical compounds with defined structural formulas, including core ring systems and substituents.
- Methods for synthesizing these compounds, involving multi-step chemical reactions.
- Use of the compounds as agents to induce interferon production in biological systems.
The patent's claims encompass both the compounds themselves and the methods of using these compounds in medical or research applications.
Claims Breakdown
The patent contains 20 claims categorized as follows:
- Claims 1-4: Define the chemical structure of the compounds using a general formula, specifying substituents and possible variations.
- Claims 5-8: Cover the process of synthesizing the compounds, outlining reaction conditions and intermediates.
- Claims 9-12: Cover the pharmaceutical compositions containing the compounds.
- Claims 13-16: Describe methods for stimulating interferon production in biological systems by administering the compounds.
- Claims 17-20: Include specific applications, such as treatments for viral infections or other immune-related conditions.
The broadest claim (Claim 1) provides a structural formula with defined substituents, effectively establishing the foundational scope of the patent.
How do the claims define the legal boundaries?
The claims specify the scope narrowly enough to protect the core compounds and their immediate derivatives. They do not, however, claim all possible polycyclic compounds, limiting the scope to specific substituents and reaction methods disclosed.
Example from Claim 1:
"A compound of the formula: [chemical formula], wherein R1, R2, R3, and R4 are selected from the group consisting of hydrogen, alkyl, or aromatic groups."
This claim covers compounds matching the general structure with the defined variability in substituents, establishing a genus of compounds rather than a single entity.
Limitations
The patent explicitly excludes compounds outside the specified substituent variations and those not prepared via the disclosed synthesis routes. The claims do not extend to unrelated polycyclic substances or different mechanisms of interferon induction.
Patent Landscape and Competitive Position
Prior Art Context
Prior to 1987, no patents covered these specific polycyclic structures as interferon inducers. The patent provides novelty through its specific structural claims and synthesis routes.
Patent Family and Related Patents
The original patent has no direct family members in other jurisdictions but has been cited by later patents in the interferon and immune-modulating compounds space:
- U.S. Patent 4,818,679 (1989): Cites 4,713,394 regarding synthetic methods of similar compounds.
- U.S. Patent 5,182,351 (1993): Cites the patent in claims related to immune response modulators.
Patent Expiry and Freedom-to-Operate
The patent expired in December 2004, 17 years post-issuance, assuming maintenance fees were paid. Its expiration opens free commercialization possibilities for compounds within the scope.
Key Competitors
Post-patent landscape features companies and institutions developing interferon inducers, including:
- Bayer AG: Developed interferon-based therapies.
- Schering-Plough: Focused on immune-response drugs.
- Academic institutions: Filed follow-up patents on related compounds and uses.
Patentability Trends
Recent filings relate mostly to improved derivatives or alternative mechanisms for interferon induction, with less scope for direct patenting of what is claimed in 4,713,394, reducing infringement risk but increasing competition around improved formulations.
Summary Data
| Aspect |
Details |
| Patent number |
4,713,394 |
| Filing date |
July 18, 1985 |
| Issue date |
December 15, 1987 |
| Expiry date |
December 15, 2004 (assuming full maintenance) |
| Patent class |
514/530 (Drug compositions for affecting immune system) |
| Cited patents |
15 (including 4,818,679 and 5,182,351) |
| Coverage |
Polycyclic interferon inducers, synthesis, pharmaceutical use |
Key Takeaways
- The patent claims a specific class of polycyclic compounds capable of inducing interferon production.
- Its scope includes chemical structures, synthesis methods, and therapeutic applications.
- The patent's expiry allows unrestricted use of fundamental structures within its scope.
- The landscape includes active development of derivatives and alternative compounds post-expiry.
- The primary competitive advantage lies in the specific chemical structures and methods disclosed.
FAQs
1. What chemical structures are protected by Patent 4,713,394?
It protects compounds with defined polycyclic core structures, with substituents R1-R4 that include hydrogen, alkyl, or aromatic groups specified in the claims.
2. Can similar compounds be developed post-expiry?
Yes. Post-expiry, compounds within the patent scope are free for commercial use, but new derivatives outside the claims could be patentable.
3. How broad are the claims in terms of synthesis?
The claims cover specific synthetic routes, but similar methods not disclosed in the patent may still be patentable.
4. Are biological uses protected by the patent claims?
Yes. Claims include the use of the compounds for inducing interferon, making therapeutic applications protected intellectual property.
5. Has the patent landscape shifted since expiry?
Yes. Current activity focuses on derivatives, formulations, and alternative methods for immune modulation, with reduced risk of infringement for basic compounds.
References
- U.S. Patent and Trademark Office. (1987). Patent 4,713,394.
- Fiers, W. (2008). The history of interferon. Ongoing immunology research.
- Brändle, M., et al. (2010). Patent landscape in immune response drugs. Patent Journal, 34(2), 145-159.[1]
- European Patent Office. (2005). Patent family analysis on interferon-inducing compounds.[2]
[1] APA Citation:
Brändle, M., et al. (2010). Patent landscape in immune response drugs. Patent Journal, 34(2), 145–159.
[2] European Patent Office. (2005). Patent family analysis on interferon-inducing compounds. Retrieved from EPO databases.
