Details for Patent: 6,642,245

Summary for Patent: 6,642,245

Title:	Antiviral activity and resolution of 2-hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane
Abstract:	A method and composition for the treatment of HIV and HBV infections in humans is disclosed that includes administering an effective amount of 2-hydroxymethyl-5-(5-fluorocytosin-1-yl)-1,3-oxathiolane, a pharmaceutically acceptable derivative thereof, including a 5' or N.sup.4 alkylated or acylated derivative, or a pharmaceutically acceptable salt thereof, in a pharmaceutically acceptable carrier. A process for the resolution of a racemic mixture of nucleoside enantiomers is also disclosed that includes the step of exposing the racemic mixture to an enzyme that preferentially catalyzes a reaction in one of the enantiomers.
Inventor(s):	Liotta; Dennis C. (Stone Mountain, GA), Schinazi; Raymond F. (Decatur, GA), Choi; Woo-Baeg (North Brunswick, NJ)
Assignee:	Emory University (Atlanta, GA)
Application Number:	08/475,339
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 6,642,245
Patent Claim Types: see list of patent claims	Use; Composition; Delivery; Dosage form;

United States Patent 6,642,245: A Detailed Analysis of Scope and Claims

Overview of the Patent

The United States Patent 6,642,245, hereafter referred to as the '245 Patent, is associated with methods for treating HIV infection in humans using emtricitabine, one of the active ingredients in drugs like Truvada® and Atripla®. This patent is owned by Emory University and licensed exclusively to Gilead Sciences.

Patent Claims

The '245 Patent includes several claims that define the scope of the invention. Here are some key aspects of these claims:

Methods for Treating HIV Infection

• The patent claims methods for treating HIV infection in humans using emtricitabine. This involves specific dosages and administration protocols that are critical for the efficacy and safety of the treatment[2].

Specific Claims

• The patent includes multiple claims, with some claims focusing on the composition of the drug and others on the method of treatment. For example, Claims 1-8 and 17-19 are related to the method of treatment, while Claims 9-16 and 20-22 pertain to other aspects of the drug's composition and use[2].

Challenges to Patent Validity

The '245 Patent has faced several challenges, particularly from generic drug manufacturers seeking to enter the market.

Notice Letters and Allegations

• In one notable instance, Teva Pharmaceuticals filed an Abbreviated New Drug Application (ANDA) and submitted a Notice Letter alleging that Claims 1-8 and 17-19 of the '245 Patent are invalid, and Claims 9-16 and 20-22 would not be infringed by their proposed generic product. This Notice Letter is a formal requirement under FDA regulations, which mandates a detailed statement of the factual and legal basis for the allegations of invalidity or non-infringement[2].

Legal Proceedings

• Following the Notice Letter, Gilead Sciences had the option to commence a patent infringement lawsuit within 45 days. Such a lawsuit could delay the FDA's approval of Teva's ANDA for up to 30 months or until a district court decision, whichever occurs first. This legal process is ongoing and highlights the complexities and challenges in navigating the patent landscape for pharmaceuticals[5].

Patent Scope and Exclusivity

Multiple Patents and Exclusivities

• The '245 Patent is part of a broader portfolio of patents protecting drugs like Atripla. Atripla, for instance, is protected by 15 patents listed in the FDA's Approved Drugs Products List. This extensive patent coverage ensures that generic versions cannot be marketed until all relevant patents have expired or been invalidated[5].

Impact on Generic Entry

• The presence of multiple patents and exclusivities significantly delays the entry of generic drugs into the market. This is because generic manufacturers must either wait for all patents to expire or successfully challenge the validity of these patents through legal proceedings. The '245 Patent, along with other related patents, forms a critical part of this barrier to generic entry[1].

Metrics for Measuring Patent Scope

Independent Claim Length and Count

• Researchers have proposed metrics such as independent claim length and independent claim count to measure patent scope. These metrics can help in assessing the breadth and clarity of patent claims. However, the '245 Patent's scope is more complex due to its involvement in a larger patent portfolio and the specific nature of its claims[3].

Economic and Regulatory Implications

Executive Order on Promoting Competition

• The Executive Order on Promoting Competition in the American Economy emphasizes the need to balance patent protections with the timely entry of generic and biosimilar drugs into the market. This order instructs the Secretary of Health and Human Services to promote competition and ensure that the patent system does not unnecessarily delay the availability of affordable drugs[1].

Collaboration Between USPTO and FDA

• The USPTO and FDA collaborate to ensure that patent examiners use all publicly available FDA information to evaluate patents. This collaboration aims to maintain robust and reliable patent rights while facilitating the entry of generic drugs into the market[1].

Key Takeaways

• Patent Claims and Scope: The '245 Patent includes specific claims related to methods for treating HIV infection using emtricitabine, with a focus on both composition and method of treatment.
• Challenges to Validity: The patent has faced challenges from generic manufacturers, which have alleged invalidity or non-infringement of various claims.
• Legal Proceedings: These challenges have led to ongoing legal proceedings that can significantly delay the approval of generic versions.
• Patent Landscape: The '245 Patent is part of a larger portfolio protecting drugs like Atripla, which delays generic entry.
• Regulatory Implications: The patent system is subject to regulatory oversight to balance innovation with competition and affordability.

FAQs

1. What is the main subject of the '245 Patent?

   • The '245 Patent pertains to methods for treating HIV infection in humans using emtricitabine.

2. Who owns the '245 Patent?

   • The '245 Patent is owned by Emory University and licensed exclusively to Gilead Sciences.

3. What are the implications of the Notice Letter filed by Teva?

   • The Notice Letter alleges invalidity or non-infringement of certain claims, which could lead to a patent infringement lawsuit and delay the FDA's approval of Teva's generic product.

4. How does the '245 Patent affect the entry of generic drugs?

   • The '245 Patent, along with other related patents, forms a barrier to generic entry by requiring generic manufacturers to wait for patent expiration or successfully challenge the patent's validity.

5. What is the role of the USPTO and FDA in managing patent protections?

   • The USPTO and FDA collaborate to ensure that patent examiners use all publicly available FDA information to evaluate patents, aiming to balance innovation with competition and affordability.

Sources

1. USPTO-FDA Report on Drug Patent and Exclusivity - USPTO
2. Case 1:14-cv-00099-IMK Document 94 Filed 01/22/15 - Insight.RPXCorp
3. Patent Claims and Patent Scope - Hoover Institution
4. Biktarvy patent expiration - Pharsight
5. Gilead Sciences Announces Notification of ANDA Filing for Atripla(R) - Gilead Sciences

Drugs Protected by US Patent 6,642,245

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 6,642,245

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	0513200		91073	Luxembourg
European Patent Office	0513200		300148	Netherlands
European Patent Office	0513200		SPC/GB04/016	United Kingdom