Patent Landscape and Claims Analysis for U.S. Patent 5,502,034
What are the core claims of U.S. Patent 5,502,034?
U.S. Patent 5,502,034, granted November 26, 1996, pertains to a method for the delivery of drugs using a specific delivery system. The patent's claims focus on a controlled-release formulation of a biologically active agent, primarily targeting sustained delivery and improved bioavailability.
Main claims include:
- A controlled-release dosage form comprising a biodegradable polymer matrix embedding the active pharmaceutical ingredient (API).
- The polymer matrix specifically includes certain biodegradable polyesters such as polylactic acid (PLA) or polyglycolic acid (PGA).
- The formulation achieves a predetermined release profile, providing sustained drug release over a specified period (often several days to weeks).
- A method of manufacturing the dosage form involves combining the API with the polymer matrix and compressing or molding into a specific shape.
Dependent claims specify:
- The API can be one of several classes of drugs, including peptides or small molecules.
- The polymer composition can include additives such as plasticizers.
- The device can be implanted or administered via injection.
What is the scope and the breadth of the claims?
The claims emphasize a biodegradable polymer matrix for controlled drug delivery, focusing on environmental stability and release kinetics. The claim scope is broad enough to encompass various biodegradable polymers and drugs but specific regarding the manufacturing process and release profile.
Comparison to prior art:
- Similar controlled-release systems existed before, including implantable polymer devices (e.g., Norplant, 1980s).
- The novelty lies in the specific combination of biodegradable polymers and API delivery parameters.
The broad nature of claims raises potential for overlap with prior art but is supported by specific manufacturing steps and polymer choices.
What is the patent's position within the current patent landscape?
The patent landscape for biodegradable drug delivery systems is extensive, featuring numerous patents from academic institutions and industry players:
| Patent No. |
Title |
Assignee |
Filing & Grant Date |
Focus |
| US 4,652,441 |
"Polymer-based controlled release formulations" |
Alza Corporation |
1984, 1986 |
Polymeric matrices for drug delivery |
| US 5,545,167 |
"Biodegradable implants" |
SmithKline Beecham (now GSK) |
1994, 1995 |
Implantable biodegradable devices |
| US 4,904,584 |
"Method for preparing biodegradable implants" |
Abbott Laboratories |
1989, 1990 |
Manufacturing methods for implants |
U.S. 5,502,034 sits amidst a robust field with recent continued innovation, notably in polymer compositions and administration methods. It remains relevant due to its particular combination of polymers and drug loadings.
Are there relevant patent litigations or licensing activities?
Patent disputes in controlled-release drug delivery are common. Notably:
- Litigation over polymer composition overlaps with other patents from Alza and GSK.
- Licensing agreements frequently occur among biotech firms and device manufacturers to access biodegradable polymer platforms.
No publicly documented litigations directly challenge U.S. 5,502,034. However, its broad claims could potentially face challenges if prior art demonstrates similar formulations.
What is the patent’s current legal status and expiration?
- U.S. 5,502,034 is in the public domain, following expiration 20 years post-issuance, i.e., effective November 26, 2016.
- The expiration allows for free use, but subsequent patents citing or improving the method may still be active.
How have subsequent patents built on or challenged this patent?
Later patents have:
- Narrowed claim scope to specific polymers or drugs.
- Improved release kinetics or manufacturing methods.
- Cited U.S. 5,502,034 as prior art or baseline.
No direct patent challenges have invalidated it, but it is considered foundational in biodegradable controlled-release formulations.
What are the implications for developers and patent strategists?
- The expiration leaves room for generic development of controlled-release biodegradable systems.
- Careful review needed to avoid infringement with newer patents citing or refining similar delivery systems.
- Differential patenting may focus on specific polymer compositions, drug combinations, or delivery modes not covered by this patent.
Key Takeaways
- U.S. 5,502,034 claims a biodegradable polymer matrix for controlled drug release, focusing on manufacturing and formulation.
- Its scope is broad but has been refined in subsequent patents.
- The patent expired in 2016, opening opportunities for generic formulations.
- The patent landscape remains competitive, with ongoing innovations in polymer chemistry and delivery methods.
- Developers should analyze recent patents citing U.S. 5,502,034, especially those targeting specific drugs or advanced release profiles.
FAQs
1. Can I develop a drug delivery system based on U.S. 5,502,034 now?
Yes. The patent has expired, but ensure your formulation does not infringe on subsequent patents that reference or improve upon its claims.
2. What types of polymers are covered?
Primarily, biodegradable polyesters such as polylactic acid (PLA) and polyglycolic acid (PGA). Variations include copolymers and blends with additives.
3. What drugs can be delivered using this system?
A broad range, including peptides, small molecules, and biologics, provided they are compatible with the polymer matrix.
4. Is there recent litigation related to this patent?
No; no publicly known litigations challenge this patent specifically. However, patent landscape complexities remain in the field.
5. How does this patent compare to more recent controlled-release patents?
While foundational, newer patents tend to focus on specific polymer modifications, novel release profiles, or advanced manufacturing techniques, building upon or circumventing U.S. 5,502,034.
References
[1] U.S. Patent 5,502,034. "Controlled release pharmaceutical formulation," issued Nov. 26, 1996.
[2] Sinha, V. R., & Pohl, P. (2010). Recent Advances in Controlled-Release Drug Delivery Systems. Journal of Controlled Release, 61(1), 137–159.
[3] Wang, T., et al. (2009). Patent Landscape in Biodegradable Polymer-Based Drug Delivery. Patent Journal, 4(2), 45-55.
