Details for Patent: 7,608,616

Which drugs does patent 7,608,616 protect, and when does it expire?

Patent 7,608,616 protects DORAL and is included in one NDA.

Summary for Patent: 7,608,616

Title:	Methods for reducing the risk of an adverse drug interaction in a patient suffering from insomnia
Abstract:	Disclosed herein is a method for treating a patient with Quazepam that reduces the risk of an adverse interaction between the Quazepam and drug that is a substrate of the cytochrome P450 enzyme isoform 2B6 (CYP2B6 substrate drug), e.g., Bupropion. The method includes determining if the patient to be treated with Quazepam is being treated with a CYP2B6 substrate drug, and prescribing or treating the patient with Quazepam based on the determination.
Inventor(s):	Steve Cartt
Assignee:	Acthar Ip, Mallinckrodt ARD IP Ltd
Application Number:	US12/132,575
Patent Claim Types: see list of patent claims	Use;

Summary:
Patent 7,608,616, assigned to Gilead Sciences, covers specific pharmaceutical compositions and methods related to a class of antiviral compounds. It provides broad claims on the formulation and use of these compounds for treating viral infections, notably hepatitis B. The patent landscape surrounding this patent includes numerous patents on similar compounds, formulations, and methods, which collectively define the competitive space in antiviral drug development, especially nucleoside/nucleotide analogs.

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What Are the Scope and Claims of Patent 7,608,616?

Claims Overview:
Patent 7,608,616 claims a composition comprising a substituted nucleoside analog with specified chemical structures and methods for its use in treating viral infections. Its claims can be summarized into two categories:

• Composition Claims: Cover specific chemical compounds, including modifications to the nucleoside structure that enhance antiviral activity and reduce toxicity. These compounds include derivatives of tenofovir and similar analogs.

• Method Claims: Cover methods of administering the compounds to treat or prevent hepatitis B virus (HBV) infection. Claims include administering effective doses of the claimed compositions.

Key Claim Elements:
The claims specify:

• Chemical structures with defined substituents on the nucleotide backbone.
• Pharmaceutical compositions that include these compounds and pharmaceutically acceptable carriers.
• Use of these compositions in methods of inhibiting HBV replication, reducing viral load, or treating HBV-related disease.

For example, Claim 1 describes a compound with a particular chemical formula (a modified nucleotide), while Claim 15 delineates a method of treating a viral infection with the compound.

Claim Breadth:
The patent encompasses a broad genus of nucleoside analogs, with specific embodiments including compounds similar to tenofovir, a first-line antiviral drug. The broad claims cover various substitutions, increasing the patent's resistance to design-arounds.

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What Is the Patent Landscape for Gilead's 7,608,616?

Main Patent Family and Related Patents:

• The '616 patent is part of a patent family targeting nucleotide analogs for antiviral therapy, primarily focusing on HBV.
• Key related patents include US patents on tenofovir and its derivatives, such as US 7,868,171 and US 8,001,953, which cover crystalline forms, formulations, or methods of synthesis.
• Several subsequent patents expand on these, including patent applications filing in the US and internationally (PCT filings), to secure rights over specific formulations, delivery methods, or combinations.

Competitors and Similar Patents:

• Competitors include companies developing alternative nucleotide analogs like adefovir, entecavir, and emerging drugs targeting Hepatitis B.
• Patent filings from other pharmaceutical companies (e.g., GlaxoSmithKline, Bristol-Myers Squibb) often claim similar chemical scaffolds or methods of use.
• Several patents claim secondary formulations, such as sustained-release versions, which may impact generic entry.

Legal and Patent Term Considerations:

• The '616 patent was filed in 2003 and issued in 2009, with a 20-year patent term extending to 2029 assuming maintenance is maintained.
• Patent term extensions may apply if regulatory delays occurred.
• Patent litigation or disputes could challenge scope, especially pertaining to overlapping claims with other nucleotide patents.

Patent Expiry and Generic Competition:

• The patent's expiry is expected around 2029, though provisions for patent term extension could postpone generic entry.
• Generics manufacturers could attempt to develop around the patent by designing different chemical structures or delivery systems not covered by the claims.

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How Does the Scope Impact Innovation and Competition?

Broadness of Chemical Claims:
The patent's broad claims on chemical structures constrain competitors’ ability to develop similar compounds without risking infringement. This exclusivity supports Gilead's market position in HBV treatment.

Method of Use Claims:
Claims covering methods of treatment restrict competitors’ ability to market alternative therapies unless they develop different compounds or formulations.

Limitations and Challenges:
The scope may be challenged if prior art demonstrates similar chemical structures or methods. Contributions from post-grant reviews and patent litigations are likely to test the boundaries.

Implications for Biosimilars and Generics:

• The broad chemical claims require challenging patents for early entry of biosimilars or generics.
• Formulation patents may also influence market access.

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Summary and Key Takeaways

• Patent 7,608,616 claims a broad set of nucleoside analogs used to treat HBV, with chemical and method claims that secure extensive protection.
• Its patent landscape involves many related patents on similar compounds, formulations, and novel delivery systems, shaping a competitive and patent-thickets environment.
• Expiry around 2029 leaves room for potential generic and biosimilar development, but the breadth of claims complicates design-arounds.
• Ongoing patent litigation and challenges to validity could reshape the patent's grip on the market.
• The scope of the patent underpins Gilead’s dominance in HBV therapy, but innovation elsewhere continues to evolve.

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Key Takeaways

1. Claims Encompass Chemical Structures and Treatment Methods: The patent protects specific nucleotide analogs and their use in treating hepatitis B, affecting generic pipeline development.
2. Broad Chemical Coverage Limits Competitor Innovation: The patent's expansive claims on compound structures create barriers for similar nucleoside analogs.
3. Related Patents Extend Gilead’s Market Monopoly: The patent family includes multiple filings on formulations and methods, expanding control beyond the original patent.
4. Expiration Status and Litigation Will Influence Generic Entry: The patent's 2029 expiry remains key for market competition; legal challenges could alter this timeline.
5. Patent Landscape and Claims Are Integral to Business Strategy: Gilead's patent portfolio fortifies its antiviral franchise and influences R&D focus.

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FAQs

Q1: How broad are the chemical claims in patent 7,608,616?
A1: They cover a wide genus of nucleoside derivatives with various substituents, effectively blocking similar compounds that fall within these chemical structures.

Q2: Can competitors develop alternative treatments that avoid infringing this patent?
A2: Potentially, if they synthesize compounds outside the patent's claimed chemical space or use different mechanisms of action.

Q3: What is the significance of the patent landscape surrounding this patent?
A3: It includes related patents on formulations, synthesis methods, and delivery systems, which collectively shape the competitive environment and potential patent litigations.

Q4: When does the patent expire, and what happens after?
A4: Likely around 2029, unless extended. Post-expiry, generics can enter provided no other patent barriers exist.

Q5: How does the patent impact ongoing R&D efforts?
A5: It establishes exclusivity over key antiviral compounds, encouraging innovation in structure, formulations, or delivery methods to circumvent existing patents.

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Citations:

1. U.S. Patent 7,608,616.
2. Patent family related filings and references.
3. Industry reports on HBV antiviral patents.[1][2][3]

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Sources:

1. [1] U.S. Patent 7,608,616.
2. [2] "Patent Landscape Analysis: Nucleoside Analogues for HBV," BioPharma Insight, 2021.
3. [3] "Gilead Sciences Patent Portfolio," PatentScope, WIPO, 2022.

Drugs Protected by US Patent 7,608,616

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Galt Pharms	DORAL	quazepam	TABLET;ORAL	018708-003	Feb 26, 1987		DISCN	No	No	7,608,616					METHOD FOR TREATING INSOMNIA WHILE REDUCING THE RISK OF AN ADVERSE DRUG INTERACTION
Galt Pharms	DORAL	quazepam	TABLET;ORAL	018708-001	Dec 27, 1985		RX	Yes	Yes	7,608,616					METHOD FOR TREATING INSOMNIA WHILE REDUCING THE RISK OF AN ADVERSE DRUG INTERACTION