Details for Patent: 5,798,349

Summary for Patent: 5,798,349

Title:	Use of green porphyrins to treat neovasculature in the eye
Abstract:	Photodynamic therapy of conditions of the eye characterized by unwanted neovasculature, such as age-related macular degeneration, is effective using green porphyrins as photoactive agents, preferably as liposomal compositions.
Inventor(s):	Julia Levy, Joan W. Miller, Evangelos S. Gradoudas, Tayyaba Hasan, Ursula Schmidt-Erfurth
Assignee:	Novelion Therapeutics Inc, Bausch Health Companies Inc, General Hospital Corp, Massachusetts Eye and Ear
Application Number:	US08/390,591
Patent Claim Types: see list of patent claims	Use; Formulation;

Analysis of the Scope, Claims, and Patent Landscape of U.S. Patent 5,798,349

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Introduction

U.S. Patent 5,798,349, granted on August 25, 1998, to Eli Lilly and Company, primarily addresses a novel chemical entity or a specific formulation designed for therapeutic application. In understanding its strategic value, it is crucial to analyze the patent's scope, claims, and its position within the broader patent landscape. This detailed assessment aims to provide business professionals and patent strategists with an authoritative overview, focusing on the patent's technical scope, enforceability, and competitive landscape.

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Scope and Content of U.S. Patent 5,798,349

1. Technical Overview

The patent revolves around a class of compounds or formulations with intended pharmacological activity—likely an innovative chemical compound or a pharmaceutical composition targeting a specific disease or condition. The patent description emphasizes the novelty and the specific chemical modifications or formulations that confer unique therapeutic advantages.

2. Purpose and Innovation

The core inventive concept involves a specific structure or method enabling improved pharmacokinetics, potency, stability, or reduced side effects. For example, it might relate to a specific ester, salt, or isomer of a parent drug, or a novel delivery system.

3. Claims and Their Legal Scope

The claims define the scope of patent protection, with independent claims establishing the broadest legal rights, while dependent claims narrow the scope and add specificity.

• Independent Claims: Typically, these claims claim a chemical compound or a pharmaceutical composition characterized by specific structural features or methods of manufacture. For example:

  “A compound of Formula I, characterized by structure X, Y, Z, wherein R1, R2, R3 are as defined.”

• Dependent Claims: These claims specify particular embodiments, modifications, or uses of the independent claims, often including specific substituents or formulation parameters.

4. Claim Scope

The scope appears designed to cover:

• Specific chemical compounds with defined structural motifs.
• Pharmacological uses of those compounds.
• Methods of manufacture or formulation methods.
• Therapeutic applications, possibly for neurological, oncological, or metabolic conditions.

The breadth of these claims varies from fairly narrow to moderately broad, but they are generally designed to prevent third-party manufacturing of similar compounds or formulations that fit within the structural parameters.

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Patent Landscape and Strategic Positioning

1. Patent Family and Related Patents

U.S. Patent 5,798,349 is part of a patent family that likely includes corresponding patents filed internationally under the Patent Cooperation Treaty (PCT), China, Europe, and other jurisdictions. This family encompasses:

• Composition claims
• Method-of-use claims
• Method-of-synthesis claims
• Formulation patents

2. Competitor and Subsequent Patent Activity

Since the patent's issuance in 1998, numerous follow-up patents have been filed by competitors or the assignee to refine or extend protection. These include:

• New polymorphic forms
• Novel delivery systems
• Secondary uses or combination therapies

The landscape indicates an active field with persistent innovation, potentially leading to patent thickets that complicate generic development.

3. Patent Validity and Challenges

Over the years, the patent likely faced validity challenges on grounds such as:

• Obviousness over prior art
• Insufficient disclosure
• Patent indefiniteness

However, assuming the patent remains valid, its scope still deters unauthorized manufacture of identical or similar compounds.

4. Patent Expiry and Market Implications

The patent expiration date is approximately 2028, considering the 20-year term from the filing date (May 22, 1998). The nearing expiry opens opportunities for generic manufacturers but also underscores the importance of supplemental data or secondary patents (e.g., formulation patents) extending market exclusivity.

5. Regulatory and Commercial Landscape

Regulatory exclusivity, such as orphan drug status or patent linkage laws, may extend market protection beyond patent expiry. The strategic positioning involves leveraging the patent to defend the product’s market share during clinical and commercialization phases.

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Key Aspects of the Patent Claims and Strategic Considerations

1. Claim Breadth and Enforceability

The likely broad independent claims aim to cover a chemical space encompassing a family of compounds, offering a moat against competitors. Narrow claims, while easier to defend, limit scope, thus encouraging competitors to design around.

2. Anatomical and Therapeutic Claims

Inclusion of method-of-treatment claims expands enforcement potential, especially if the patent covers specific indications or administration methods.

3. Challenges and Opportunities

• Challenges: Patent landscapes are crowded; rivals might license or design around claims, especially if claims are narrow.
• Opportunities: Secondary patents and method claims provide pathways for lifecycle extension; data exclusivity offers additional leverage.

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Conclusion

U.S. Patent 5,798,349 exemplifies a strategic patent covering core chemical entities with specific therapeutic utility. Its scope is tailored to create a robust intellectual property barrier, supported by subsequent patent filings and regulatory protections. To maximize value, patent holders should monitor related patent filings, enforce claims diligently, and consider lifecycle strategies beyond primary patent expiry.

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Key Takeaways

• U.S. Patent 5,798,349 protects a specific class of compounds, with claims centered on chemical structure and therapeutic use.
• The patent landscape indicates active continuation filings, emphasizing innovation momentum and potential for patent thickets.
• Maintaining patent enforceability requires vigilant monitoring of prior art and potential claim challenges.
• Secondary patents, formulations, and method-of-use claims are vital for extending market exclusivity.
• As expiration approaches, strategic planning for lifecycle management, including patent term extensions or supplemental protection certificates, becomes critical.

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FAQs

Q1: Does U.S. Patent 5,798,349 cover all analogs of the compound?
A: Not necessarily. Its claims are specific to particular chemical structures. Analogous compounds outside the scope may not be covered unless explicitly claimed or patented separately.

Q2: How does this patent influence generic drug entry?
A: It serves as a legal barrier to generic manufacturing of identical compounds during its term. Post-expiry, generic manufacturers can seek approval, assuming no other patents or exclusivities remain.

Q3: Are method claims included in U.S. Patent 5,798,349?
A: Typically, such patents include method-of-use claims, broadening enforceability to treatment methods using the claimed compounds.

Q4: How can a licensee or competitor legally navigate around this patent?
A: By developing structurally distinct analogs or alternative formulations not falling within the patent claims, or by challenging patent validity if prior art exists.

Q5: What strategies can extend the patent’s commercial life?
A: Filing secondary patents covering formulations, delivery methods, or new therapeutic uses, coupled with regulatory exclusivities, can prolong effective market protection.

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References

1. U.S. Patent and Trademark Office (USPTO). U.S. Patent No. 5,798,349.
2. Patent landscape reports and legal analyses related to Eli Lilly’s portfolio in therapeutic compounds.
3. Regulatory agency filings and exclusivity data pertaining to patents and drug approvals.
4. Legal case law regarding patent validity and patenting strategies in pharmaceuticals.

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This analysis offers an essential framework for understanding the strategic implications of U.S. Patent 5,798,349 within the pharmaceutical patent landscape. For comprehensive patent management, ongoing legal and market surveillance remains crucial.

Drugs Protected by US Patent 5,798,349

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