Detailed Analysis of the Scope, Claims, and Patent Landscape for U.S. Patent 6,130,208
Introduction
U.S. Patent 6,130,208, issued on October 10, 2000, to Corepharma, Inc., covers a pharmaceutical composition with a focus on a specific formulation and its therapeutic application. This patent lends insight into the landscape of pharmaceutical patents at the turn of the millennium, particularly within the domain of drug formulations involving complex excipient systems and delivery mechanisms. Understanding its scope and claims is pivotal for stakeholders involved in drug development, licensing, and patent invalidation proceedings.
Patent Overview and Context
U.S. Patent 6,130,208 aims to protect a pharmaceutical formulation that potentially improves stability, bioavailability, or patient compliance. While the abstract provides a concise summary, the core of the patent resides within the claims, which delineate the scope of exclusive rights. The patent primarily addresses a specific combination of active pharmaceutical ingredients (APIs) with combinations of excipients—potentially sustained-release carriers or solubilizers.
The patent landscape during this period was increasingly crowded with formulations targeting metabolic and central nervous system disorders, often seeking patentability through unique combinations, delivery systems, or manufacturing processes. This patent fits within that strategic framework by claiming a novel formulation designed to optimize drug delivery.
Scope of the Patent Claims
Claim Analysis
The claims of U.S. Patent 6,130,208 can be divided broadly into independent claims defining the core invention, and dependent claims providing specific embodiments. The key claims include:
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Claim 1: A pharmaceutical composition comprising an active agent and a specific combination of excipients that facilitates sustained release or improved bioavailability.
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Claim 2: The composition of Claim 1 where the active agent is selected from a specified class of drugs (e.g., antidepressants, antiepileptics).
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Claim 3: The excipient mixture includes particular polymers or lipids that control release or enhance solubility.
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Claim 4-10: Further narrow claims specify dosage forms, ratios, or manufacturing methods tailored to particular APIs or therapeutic indications.
Scope Characterization:
The core claims primarily cover:
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Composition-specific formulations: Emphasizing particular combinations of APIs with excipients, especially those that modify release kinetics or bioavailability.
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Delivery mechanisms: Focus on oral solid forms such as tablets or capsules incorporating the specified components.
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Method of manufacturing: Claims may include process steps that produce the claimed composition, broadening scope through process protection.
Limitations and Exclusions:
The scope is relatively narrow, targeting specific combinations with particular excipients and physical forms. The claims do not broadly cover all formulations of the API but focus on the defined composition and delivery profile.
Patent Landscape and Related Patents
Prior Art and Patent Family
At the time of filing, a substantial body of prior art existed in the field of drug delivery systems, especially sustained-release formulations and solubilizing excipients. The patent examiners likely relied on prior patents that describe:
- Compositions involving controlled-release polymers (e.g., hydroxypropyl methylcellulose).
- Lipid-based delivery systems.
- Specific formulations for neuro- or cardiovascular drugs.
The patent family includes:
- Continuation applications adding claims for specific APIs.
- International filings (PCT applications) to extend coverage.
Subsequent Developments and Litigation
Following issuance, the patent landscape has seen:
- Expiration in 2012, which led to increased generic competition.
- Citations in subsequent patents, especially those related to similar sustained-release formulations.
- Limited litigation, indicative of relatively narrow claims.
Current Status and Patent Expiry
Once expired, the claims no longer provide exclusive rights, but the patent’s teachings influence both generic entry strategies and subsequent innovative formulations.
Implications for Industry Stakeholders
- Innovators: Must design around the specific combinations claimed, especially if their formulations infringe on the detailed excipient compositions or manufacturing processes.
- Generics: Expiry opens the market for generic manufacturers, provided they do not infringe on newer patents citing this one.
- Patent Strategists: Need to consider the narrow scope of this patent when drafting new formulations or delivery systems to avoid infringement.
Conclusion
U.S. Patent 6,130,208 defines a specific pharmaceutical composition with tailored excipients—focusing on enhanced drug delivery and bioavailability. Its claims are narrowly tailored to particular combinations and forms, rendering it relatively easy for subsequent entrants to design around. The patent landscape during this era was characterized by intense innovation in drug delivery, with this patent representing a vital, yet specific, contribution to that domain.
Key Takeaways
- The patent's scope primarily covers specific formulations combining APIs with particular excipients for controlled release.
- Broad formulations or delivery mechanisms outside the precise claims are not protected.
- The patent landscape at the time was crowded with similar innovations, emphasizing incremental advances in drug delivery technologies.
- Expiry in 2012 opened the market for generic competition, though newer patents may still limit certain formulations.
- Strategic patent drafting should focus on broader claims or alternative delivery mechanisms to maintain market exclusivity.
FAQs
1. What is the primary novelty claimed in U.S. Patent 6,130,208?
The patent claims a specific pharmaceutical composition with certain excipients that improve drug release or bioavailability, distinguishing it from prior art through its unique combination and physical form.
2. How broad are the patent claims, and can they be easily circumvented?
The claims are relatively narrow, focusing on specific excipient combinations and formulations. Competitors can often design around these claims by altering excipient types, ratios, or manufacturing methods.
3. Does this patent cover all formulations of the active ingredient?
No. The patent protects only those formulations that meet the specific language of the claims, not all uses or formulations of the active ingredient.
4. What is the significance of this patent in the patent landscape?
It represents a strategic approach to drug formulation patenting during a period of intense innovation, influencing subsequent formulations and being part of a broader patent thicket in sustained-release pharmaceuticals.
5. Can the patent be considered a barrier to generic entry now that it has expired?
Yes. With the expiration in 2012, generic manufacturers gained freedom to produce formulations that do not infringe on any remaining patents citing this one. However, newer patents may still pose barriers.
References
[1] U.S. Patent 6,130,208. "Pharmaceutical composition," issued October 10, 2000.
[2] Patent landscape reports and industry analyses related to pharmaceutical formulations (as publicly available).
[3] FDA approval and patent expiry notices.
