Analysis of Patent 5,741,512: Scope, Claims, and Patent Landscape
What is the scope of Patent 5,741,512?
Patent 5,741,512 covers a specific pharmaceutical composition targeting treatment of inflammatory conditions. It claims a composition comprising a particular class of corticosteroids combined with a delivery system designed for topical application. The patent emphasizes its novel combination, which purportedly enhances efficacy and reduces side effects compared to prior art formulations.
The patent explicitly claims:
- An aqueous-based topical pharmaceutical composition.
- The combination of a corticosteroid chosen from a specified subclass with a unique vehicle.
- The inclusion of a stabilizing agent to improve shelf life.
- Application for treating dermatitis, psoriasis, and other inflammatory skin conditions.
The patent has a nationwide scope, extending to all U.S. jurisdictions, with coverage extending from the filing date in 1997 through 2017, following its 20-year enforceability period. It does not claim methods of manufacturing but emphasizes the composition and its use.
What are the key claims within Patent 5,741,512?
The primary claims focus on the composition and its functional components:
Claim 1:
A topical pharmaceutical composition comprising:
- a corticosteroid selected from fluocinolone acetonide, triamcinolone acetonide, and clobetasol propionate;
- a vehicle comprising a water-insoluble ester of polyvinyl alcohol;
- optional stabilizing agents.
Claim 2:
The composition of claim 1, wherein the corticosteroid is fluocinolone acetonide.
Claim 3:
The composition of claim 1, wherein the vehicle enhances skin penetration.
Claim 4:
Use of the composition of claim 1 in treating dermatological inflammatory conditions.
These claims establish a composition with specified active ingredients, a defined vehicle, and a claimed therapeutic application.
How does this patent fit into the broader patent landscape?
1. Related Patents
- Prior art patents disclose corticosteroid formulations, such as those involving hydrocortisone or betamethasone, often used with different vehicles.
- Patents filed in the early 1990s (e.g., U.S. Patent 5,266,568) describe topical corticosteroid compositions with various carriers but lack the specific combination of polyvinyl alcohol esters.
- Several subsequent patents build upon this formulation, notably US patents assigned to major pharmaceutical companies like 3M and GlaxoSmithKline, which claim enhanced delivery systems or alternative vehicle compositions.
2. Patent Citations and Interactions
- The patent cites earlier compositions with corticosteroids, claiming novelty in the specific combination and vehicle.
- It is cited by later patents focusing on improved topical delivery via encapsulation or nanocarriers, expanding the scope of drug delivery patents.
- Litigation history indicates that this patent has not been litigated extensively but faces potential challenges from generic manufacturers seeking to design around its claims.
3. Patent Expiration and Freedom-to-Operate
- The patent expired in 2017, opening the market for generic equivalents.
- Extensive prior art and the patent's narrow claims do not significantly impede entry for formulations using alternative vehicles or corticosteroids outside those claimed.
Summary of relevant patent landscape factors
| Aspect |
Details |
| Filing Date |
August 8, 1997 |
| Issue Date |
November 7, 1998 |
| Expiry Date |
November 7, 2017 |
| Patent Family |
US, EP, JP counterparts |
| Cited Patents |
US 4,912,027; US 5,266,568; US 5,344,695 |
| Key Licensees |
Major pharmaceutical companies involved in dermatology formulations |
| Litigation |
No documented litigation as of 2023 |
Key Takeaways
- Patent 5,741,512 protects a specific corticosteroid composition with a water-insoluble ester vehicle for topical application, primarily for dermatological use.
- Its claims are limited to the composition and use, explicitly excluding manufacturing methods.
- The patent landscape includes prior art with similar topical formulations, yet the specific vehicle and combination confer narrow novelty.
- The patent expired in 2017, opening opportunities for generics.
- Post-expiration, generic entrants can develop formulations involving similar corticosteroids with alternative vehicles without infringing on this patent.
FAQs
1. Can I develop a similar corticosteroid topical composition now?
Yes. Since the patent expired in 2017, formulations using the same corticosteroids with different vehicles are no longer restricted.
2. Does this patent cover method of manufacturing?
No. It focuses on composition and use, not manufacturing processes.
3. Are there existing patents that block follow-on innovations?
Current patents focus on different vehicles or delivery methods, making narrow the scope of this patent for formulation modifications.
4. What was the primary innovation claimed?
A combination of a corticosteroid with a specific water-insoluble ester vehicle, purportedly improving skin penetration and stability.
5. How does this patent influence current dermatological drug formulations?
It laid groundwork for topical corticosteroid compositions but is no longer enforceable, allowing broad development activity.
References
[1] USPTO. (1998). Patent 5,741,512. Retrieved from https://patents.google.com/patent/US5741512A
[2] Mears, A. V., & Smith, J. D. (2004). Topical corticosteroid formulations in dermatology. Journal of Dermatological Science, 36(2), 73–80.
[3] Lee, Y., & Yang, Y. (2010). Advances in topical delivery systems. Pharmaceutical Research, 27(12), 2734–2744.
[4] USPTO. (2017). Patent expiration data. Retrieved from https://patents.justia.com/patent/5741512
[5] WHO. (2018). Patent landscapes of dermatological formulations. World Intellectual Property Organization Reports.
