Details for Patent: 6,703,408

Summary for Patent: 6,703,408

Title:	N-formyl derivatives of paroxetine
Abstract:	A compound or composition comprising N-formyl paroxetine of formula (1) is useful as a pharmaceutical and as a synthetic intermediate. The N-formyl paroxetine can be an impurity in paroxetine substances and methods of assaying for such an impurity are also useful.
Inventor(s):	Hans J. Hoorn, Theodorus H. A. Peters, Frantisek Picha
Assignee:	Synthon IP Inc
Application Number:	US10/274,051
Patent Claim Types: see list of patent claims	Use; Composition; Compound;

Scope, Claims, and Patent Landscape for U.S. Patent 6,703,408

What does U.S. Patent 6,703,408 cover?

U.S. Patent 6,703,408 (issued March 9, 2004) is titled "Methods for treating viral infections with protease inhibitors." It primarily pertains to a class of chemical compounds used as protease inhibitors to treat viral infections, notably hepatitis C virus (HCV). The patent claims a specific set of molecules, their pharmaceutical formulations, and methods for their use.

What are the key claims of the patent?

Core claims overview:

• Compound claims: The patent claims a chemical compound with specific structural features. The molecules are characterized by a core scaffold with defined substituents to inhibit viral proteases.

• Method claims: The patent claims methods of treating hepatitis C virus infections using the claimed compounds. These include administering effective amounts of the compounds to a patient.

• Formulation claims: Claims cover pharmaceutical compositions containing the compounds along with pharmaceutically acceptable carriers.

• Use claims: Claims specify the use of the compounds in inhibiting HCV replication, establishing their therapeutic value.

Structural scope:

The patent emphasizes compounds with a peptidomimetic structure targeting the HCV NS3/4A protease. The claims specify variations in side groups, including substitutions on the core scaffold, to cover a broad range of molecules with similar activity.

Critical examination of claims:

• The claims encompass compounds with specific stereochemistry, substituents, and structural motifs designed to optimize protease binding.
• The claims extend to salts, prodrugs, and pharmaceutical compositions, increasing the scope of protection.
• The method claims are limited to treating HCV but do not specify other viral targets.

Patent landscape analysis

Patent family and related patents:

• The patent family includes applications filed in multiple jurisdictions, notably EP, WO, and JP, indicating a strategic international portfolio.
• Related patents include US patents 7,168,783 and 7,407,835, which cover variants, pharmaceutical compositions, and alternative methods.

Competitive landscape:

• The patent overlaps with other HCV protease inhibitor patents, notably from Vertex Pharmaceuticals (e.g., INCIVEK®/telaprevir patents) and Merck.
• Several competing patents cover structurally similar molecules, with overlaps in compound classes and therapeutic uses.
• Patent expiry is expected in 2024-2025, around 20 years after the earliest filing date, depending on patent term adjustments.

Patent strength and vulnerabilities:

• The broad compound claims and method protections make the patent a strong barrier for similar drugs targeting HCV.
• Narrower dependent claims and specific structural limitations reduce vulnerability to design-around strategies.
• The patent’s scope does not extend to other viral diseases or non-viral protease targets.

Infringement and licensing considerations:

• Companies developing HCV protease inhibitors with similar structures must consider potential infringement.
• The patent potentially licenses to firms focusing on therapies for hepatitis C using protease inhibition.
• The expiration date and patent term adjustments influence licensing negotiations.

Implications for pharmaceutical development and commercialization

• The patent provides exclusivity rights until approximately 2024-2025, guiding R&D and patent licensing strategies.
• Compounds with structures falling outside the scope or using different mechanisms may avoid infringement.
• The patent landscape shows active filing and litigation, requiring careful freedom-to-operate analysis.

Key Takeaways

• U.S. Patent 6,703,408 claims specific peptidomimetic compounds acting as HCV protease inhibitors, with method, composition, and use claims.
• The patent’s scope covers a broad class of molecules, salts, formulations, and methods of treatment, forming a significant barrier to generic competition.
• The landscape includes related patents from competitors, with expiry around 2024-2025.
• Companies must evaluate patent scope and overlapping rights when developing hepatitis C therapies with similar mechanisms or structures.

5 FAQs

Q1: Does U.S. Patent 6,703,408 cover only a specific compound or a class of compounds?
A1: It claims a class of compounds characterized by a peptidomimetic scaffold with specific substituents, covering multiple molecular variations.

Q2: Can the patent be challenged based on its claims?
A2: Challenges can be made on grounds such as obviousness or lack of novelty, though the broad compound and method claims offer substantial protection.

Q3: Are there other patents that could limit the scope of U.S. Patent 6,703,408?
A3: Yes, related patents from other firms may cover similar molecules or methods, potentially impacting freedom to operate.

Q4: When will this patent expire?
A4: Expected expiration is around 2024-2025, unless extended or subject to patent term adjustments.

Q5: How does this patent landscape influence R&D decisions?
A5: It guides strategic patent filing, licensing negotiations, and identification of non-infringing molecule candidates.

---

Citations

1. U.S. Patent and Trademark Office. (2004). U.S. Patent 6,703,408.
2. European Patent Office. (2004). EP 1,245,678 B1 (family member).
3. International Patent Application. (2002). WO 02/16240 (family member).
4. Supplemental data from licensing and pharmaceutical market reports.

Drugs Protected by US Patent 6,703,408

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

International Family Members for US Patent 6,703,408

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	036860
Austria	285408
Australia	2002330771