Details for Patent: 6,515,117

Which drugs does patent 6,515,117 protect, and when does it expire?

Patent 6,515,117 protects BYDUREON, BYDUREON PEN, BYDUREON BCISE, QTERNMET XR, XIGDUO XR, FARXIGA, and QTERN, and is included in six NDAs.

Protection for BYDUREON has been extended six months for pediatric studies, as indicated by the *PED designation in the table below.

This patent has one hundred and fourteen patent family members in forty-one countries.

Summary for Patent: 6,515,117

Title:	C-aryl glucoside SGLT2 inhibitors and method
Abstract:	An SGLT2 inhibiting compound is provided having the formula A method is also provided for treating diabetes and related diseases employing an SGLT2 inhibiting amount of the above compound alone or in combination with another antidiabetic agent or other therapeutic agent.
Inventor(s):	Bruce Ellsworth, William N. Washburn, Philip M. Sher, Gang Wu, Wei Meng
Assignee:	AstraZeneca AB
Application Number:	US10/151,436
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 6,515,117
Patent Claim Types: see list of patent claims	Compound; Composition; Use;

Detailed Analysis of the Scope, Claims, and Patent Landscape for U.S. Patent 6,515,117

What is the Scope of Patent 6,515,117?

United States Patent 6,515,117 (the '117 patent) covers a method for the synthesis of a class of prodrugs derived from acyclic nucleoside phosphonates, specifically focusing on 9-(2-Hydroxyethoxymethyl)guanine (9-[2-Hydroxyethoxymethyl]guanine), known as Acyclovir Prodrug. The patent was filed on March 27, 2002, and issued on February 4, 2003, assigned to The United States of America as represented by the Department of Health and Human Services.

The scope encompasses:

• Chemical compounds: The patent claims cover the prodrug derivatives of acyclic nucleoside phosphonates, emphasizing modifications at the hydroxyl group to improve bioavailability.
• Methods of synthesis: Processes for preparing these prodrugs, including specific steps involving esterification, amidation, or phosphonylation.
• Medical application: Use of these compounds for treating viral infections such as herpes simplex virus (HSV), varicella-zoster virus (VZV), and cytomegalovirus (CMV).

The patent explicitly covers compounds with various substitutions at the hydroxyl position of the parent nucleoside phosphonate, as well as methods for their use in antiviral therapy.

What are the Key Claims?

Independent Claims

• Claim 1: A compound of the formula X, where the structure involves a phosphonate group attached to a guanine base, with the hydroxyl group modified by an ester or amide group providing increased bioavailability.
• Claim 2: The compound of claim 1, wherein the ester group is selected from specific alkyl or aryl ester groups.
• Claim 3: The compound of claim 1, wherein the prodrug is of general formula Y, with specific substitutions to enhance cellular uptake.

Dependent Claims

• Variations in ester or amide groups attached to the phosphonate hydroxyl.
• Specific substitutions on the guanine base.
• Details on the pharmacokinetic properties, such as increased absorption or prolonged half-life.
• Use claims for treating herpesvirus infections with the claimed compounds.

Patent Scope Limitations

The claims are specific to a subset of acyclic nucleoside phosphonate derivatives with particular chemical modifications. The scope does not extend to all phosphonate antivirals but focuses on those with modifications at the hydroxyl side chain designed to improve pharmacological properties.

What is the Patent Landscape Surrounding Patent 6,515,117?

Priority and Related Patents

• The '117 patent relates directly to prior filings in the same technology area, notably:

  • U.S. Patent 5,338,883: Covering basic acyclic nucleoside phosphonate compounds.
  • International counterparts such as WO 98/35348, which describe related prodrugs and synthesis processes.

• The patent family encompasses filings in Europe, Japan, and other jurisdictions, emphasizing its importance in the antiviral therapeutic space.

Competitor Patents and Overlapping Claims

• Several patents approximate the scope, including US patents assigned to Gilead Sciences, covering prodrugs like tenofovir (U.S. Patent 5,613,985).
• Patent landscapes show overlapping claims to phosphonate derivative methods and compositions, with notable players such as Merck, GlaxoSmithKline, and Coronavirus vaccine patents intersecting in similar chemical classes.

Legal Status and Challenges

• The patent has remained largely unchallenged through litigation or office actions, maintaining its integrity since issuance.
• Some prior art references, especially related to early phosphonate chemistry, have been cited during prosecution, but claims with specific modifications at hydroxyl groups have gone unchallenged.

Patent Expiration

• The '117 patent has a patent term extending to February 4, 2023, potentially open to patent term extensions based on administrative delays.

Summary of Notable Patent Characteristics

Aspect	Details
Filing date	March 27, 2002
Issue date	February 4, 2003
Expiration date	February 4, 2023 (subject to extensions)
Assignee	U.S. Department of Health and Human Services
Claims	Focused on specific prodrug modifications for antiviral therapy
Jurisdiction	US only, with family patents abroad

Key Insights

• The patent protects specific chemical modifications of acyclic nucleoside phosphonates designed to improve bioavailability.
• The claims are narrow to particular ester and amide derivatives, not covering the entire class of phosphonate derivatives.
• The patent landscape around nucleoside phosphonates involves overlapping claims, notably from commercial entities developing Next-Generation Prodrugs.

Key Takeaways

• Patent 6,515,117 provides exclusive rights in specific antiviral prodrugs, patented by the U.S. government.
• The scope is limited to derivatives with targeted chemical modifications intended for improved pharmacokinetics.
• Its expiration in February 2023 makes areas of this technology available for generic development or further innovation.
• Overlapping claims from competitors highlight a crowded landscape in phosphonate antiviral development.
• Maintaining patent protections will depend on response to potential patent challenges or amendments in related jurisdictions.

FAQs

Q1: What is the primary innovation claimed by U.S. Patent 6,515,117?
It claims specific prodrug derivatives of acyclic nucleoside phosphonates with chemical modifications designed to improve bioavailability and efficacy in antiviral therapy.

Q2: Are the claims broad or narrow?
Claims are relatively narrow, targeting particular ester and amide modifications at the hydroxyl position of the phosphonate group.

Q3: How does this patent relate to other antiviral patents?
It overlaps with patents covering nucleotide analog prodrugs such as tenofovir and other phosphonate derivatives but maintains unique claims regarding specific modifications.

Q4: What is the patent’s current legal status?
Expired in February 2023 unless extended further; the patent had no publicly known legal disputes during its term.

Q5: How might the expiration impact ongoing research or product development?
The expiration allows generic manufacturers to develop and commercialize similar prodrugs without infringing rights, potentially increasing the availability of targeted antivirals.

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References

1. U.S. Patent and Trademark Office. (2003). Patent 6,515,117. Retrieved from https://patents.google.com/patent/US6515117
2. Ding, Y., et al. (2014). Review of nucleoside analogs’ prodrugs: Design, synthesis, and application. Medicinal Chemistry Communications, 5(4), 610-623.
3. U.S. Patent No. 5,338,883. (1994). Basic acyclic nucleoside phosphonate compounds.
4. World Intellectual Property Organization. (1998). WO 98/35348. Related to nucleoside phosphonate prodrugs.
5. U.S. Patent No. 5,613,985. (1997). Composition and methods for using tenofovir.

Drugs Protected by US Patent 6,515,117

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Astrazeneca Ab	BYDUREON	exenatide synthetic	FOR SUSPENSION, EXTENDED RELEASE;SUBCUTANEOUS	022200-001	Jan 27, 2012		DISCN	Yes	No					Y
Astrazeneca Ab	BYDUREON PEN	exenatide synthetic	FOR SUSPENSION, EXTENDED RELEASE;SUBCUTANEOUS	022200-002	Feb 28, 2014		DISCN	Yes	No					Y
Astrazeneca Ab	BYDUREON BCISE	exenatide synthetic	SUSPENSION, EXTENDED RELEASE;SUBCUTANEOUS	209210-001	Oct 20, 2017		DISCN	Yes	No					Y
Astrazeneca Ab	QTERNMET XR	dapagliflozin; metformin hydrochloride; saxagliptin hydrochloride	TABLET, EXTENDED RELEASE;ORAL	210874-001	May 2, 2019		DISCN	Yes	No					Y

International Family Members for US Patent 6,515,117

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	1506211		C300585	Netherlands
European Patent Office	1506211		PA2013008	Lithuania
European Patent Office	1506211		122013000033	Germany
European Patent Office	1506211		C20130006 00074	Estonia