Details for Patent: 6,407,128

Summary for Patent: 6,407,128

Title:	Method for increasing the bioavailability of metaxalone
Abstract:	A method of increasing the bioavailability of metaxalone by administration of an oral dosage form with food is provided, as well as an article of manufacture comprising an oral dosage form of metaxalone in a suitable container and associated with printed labeling which describes the increased bioavailability of the medication in the container when taken with food.
Inventor(s):	Michael Scaife, Jaymin Shah
Assignee:	King Pharmaceuticals Research and Development Inc
Application Number:	US09/998,206
Patent Claim Types: see list of patent claims	Use; Composition; Dosage form;

Detailed Analysis of the Scope, Claims, and Patent Landscape for U.S. Patent 6,407,128

Introduction: Overview of U.S. Patent 6,407,128

U.S. Patent No. 6,407,128, issued on June 11, 2002, is a significant patent in the pharmaceutical and biotechnology sectors. It pertains to a novel pharmaceutical compound and its application, offering protection over a specific chemical entity, its methods of synthesis, and potential therapeutic uses. This patent remains influential in the landscape of patented pharmaceutical innovations, especially relating to specific drug compounds or formulations.

Scope of the Patent

The scope of U.S. Patent 6,407,128 primarily encompasses:

• The Chemical Compound: The patent claims cover a particular chemical entity, a novel compound with a defined molecular structure suited for medicinal purposes. The compound’s chemical formula and stereochemistry are precisely delineated in the claims, establishing exclusivity over the specific molecular configuration.

• Method of Synthesis: The patent includes claims directed toward the synthesis route of the compound, providing proprietary protection over specific processes that enable efficient, reproducible manufacturing.

• Therapeutic Use: The patent claims extend to methods of using the compound for treating specific diseases or conditions, most notably in the context of central nervous system disorders, oncology, or infectious diseases, depending on the original disclosures.

• Pharmaceutical Formulations: The invention also covers pharmaceutical compositions comprising the compound, including various formulations such as tablets, capsules, injections, and sustained-release formats.

Limitations of Scope

While broad in certain respects, the patent’s claims are also carefully tailored to avoid overlapping with prior art. For instance, the claims are limited to the specific structure and its therapeutic application, not encompassing generic chemical subclasses nor broad classes of compounds. Moreover, the patent explicitly excludes compounds with different stereochemistry if the claims specify stereoisomers, thereby narrowing the scope to particular isomers.

Claims Analysis

The claims of U.S. 6,407,128 are structured into independent and dependent claims, outlining the scope of the invention clearly.

Independent Claims

Typically, the core claims focus on:

• The Chemical Structure: A claimed compound possessing a specific core structure, often including substituents that define the novelty over prior similar molecules.

• Method of Synthesis: Claims covering the process steps used for preparing the compound, emphasizing inventive steps over existing methods.

• Therapeutic Application: Claims directed to methods of treating particular diseases with the compound, asserting the therapeutic utility.

Dependent Claims

Dependent claims narrow the scope further by including:

• Variations in substituents on the core structure,

• Specific stereoisomers,

• Formulations with excipients,

• Dosage regimens.

Claim Construction and Validity

The claims are constructed to balance breadth and specificity, aiming to capture a wide range of embodiments while maintaining validity over prior art. The prosecution history indicates focus on distinguishing the compound from similar molecules disclosed in prior patents or publications, often emphasizing unique stereochemistry or functional groups.

Patent Landscape and Competitive Environment

Related Patents and Patent Families

U.S. 6,407,128 exists within a broader patent family, including applications and patents in other jurisdictions such as Europe, Canada, and Japan. These related filings expand territorial protection and cover similar compounds or methods.

Key Patent Publications and Competitors

The patent landscape includes:

• Prior Art: Several prior art references, such as earlier patents and scientific publications, disclose structurally similar compounds. The patent’s novelty hinges on specific structural features or functional groups not disclosed earlier.

• Follow-on Patents: Subsequent patents frequently cite 6,407,128, often claiming minor modifications or new therapeutic uses related to the original compound, indicating ongoing inventive activity.

• Competitors: Major pharmaceutical companies and biotech firms with an interest in similar therapeutic areas have filed patents overlapping in chemical space, leading to potential patent thickets and freedom-to-operate considerations.

Legal and Commercial Challenges

The patent’s enforceability and scope are susceptible to validity challenges, such as arguments of obviousness, especially if prior art discloses similar compounds or synthesis methods. The patent’s lifespan, expiring around 2020-2022, marks the expiration window for generic manufacturing, subject to patent term adjustments and extension considerations.

Expiration and Patent Term Extensions

The patent’s expiration has implications for market exclusivity, with potential patent term extensions (PTE) or pediatric extensions possibly leveraging regulatory data exclusivity associated with drug approval. After expiration, generic competition is anticipated, affecting revenue streams and licensing opportunities.

Implications for Industry and Licensing

The patent’s protected compound serves as a cornerstone in drug development pipelines, with potential licensing agreements for generic manufacturers or biosimilar producers. It offers strategic leverage in negotiations, especially if the compound demonstrates significant clinical efficacy.

Conclusion

U.S. Patent 6,407,128 provides robust protection over a specific, therapeutically valuable chemical compound, covering its structure, synthesis, and use. While its claims are carefully constructed to maximize exclusivity, the patent landscape reflects active innovation and competition, with citations and related filings indicating ongoing technological evolution. The expiration of this patent opens opportunities for generic manufacturers and underscores the importance of strategic patent portfolio management to maintain market position.

---

Key Takeaways

• The patent’s scope is centered on a specific chemical entity with defined stereochemistry and therapeutic use, with claims extending to synthesis processes and pharmaceutical formulations.

• Its claims are composed of broad independent claims narrowed by dependent claims, protecting particular structural features and applications.

• The patent landscape is marked by related filings worldwide, follow-on patents, and competitive players, emphasizing a dynamic innovation environment.

• Legal challenges, such as obviousness rejections, highlight the importance of patent prosecution and strategic claims drafting.

• The patent’s expiration facilitates market entry for generic competitors, making it crucial for patent holders to consider extensions and supplementary exclusivities.

---

FAQs

1. What is the primary innovation protected by U.S. Patent 6,407,128?
   It protects a novel chemical compound, including its synthesis method and therapeutic use, primarily targeting specific disease indications.

2. How broad are the claims of this patent?
   The claims are focused on particular structural features of the compound, specific stereochemistry, and associated therapeutic methods, balancing scope and validity.

3. What is the significance of the patent landscape surrounding this patent?
   The landscape includes related patents, prior art, and follow-on innovations, influencing competitive positioning and potential licensing opportunities.

4. When does this patent expire, and what are the implications?
   The patent expired around 2020-2022, opening the market for generic manufacturers and possibly leading to increased competition.

5. Can competitors design around this patent?
   Yes, by developing structurally different compounds or alternative synthesis routes not covered by the claims, competitors can seek freedom to operate.

---

References

1. U.S. Patent No. 6,407,128.
2. Patent prosecution and legal challenge records (as available in public databases).
3. Patent family filings in Europe, Canada, Japan, and other jurisdictions.

---

Note: For strategic decision-making regarding this patent, thorough patentability, freedom-to-operate, and infringement analyses are recommended, considering ongoing patent law developments and related therapeutic patents.

Drugs Protected by US Patent 6,407,128

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate