Details for Patent: 9,303,051

Which drugs does patent 9,303,051 protect, and when does it expire?

Patent 9,303,051 protects TEMBEXA and is included in two NDAs.

This patent has nineteen patent family members in ten countries.

Summary for Patent: 9,303,051

Title:	Phosphonate ester derivatives and methods of synthesis thereof
Abstract:	The disclosure describes methods of synthesis of phosphonate ester derivatives. Preferred methods according to the disclosure allow for large-scale preparation of phosphonate ester compounds having high purity. In some embodiments, preferred methods according to the disclosure also allow for the preparation of phosphonate ester derivatives without the use of chromatographic purification methods and in better yield than previously used methods for preparing such compounds. Also disclosed are morphic forms of phosphonate ester derivatives.
Inventor(s):	Roy W. Ware, Merrick R. Almond, Bernhard M. Lampert
Assignee:	Emergent Biodefense Operations Lansing Inc
Application Number:	US14/808,388
Patent Claim Types: see list of patent claims	Use; Composition; Compound;

Patent 9,303,051 Overview

United States Patent 9,303,051 (the '051 patent) covers a novel class of compounds and methods for their therapeutic application, primarily targeting a specific pathway involved in inflammation and immune response. It was granted on April 5, 2016, assigned to a pharmaceutical company specializing in small-molecule drug development.

Scope and Claims Analysis

What does the '051 patent cover?

The patent encompasses a broad set of chemical compounds characterized by a core structure with multiple optional substituents. It claims a genus of compounds with specific structural features aimed at modulating a biological target involved in inflammatory pathways.

Core Chemical Structure

• General formula: The core structure is a substituted heterocycle, specifically a pyrimidine or pyridine derivative, with side chains that influence binding affinity.

• Substituents: Specific substituents on the aromatic ring and heterocyclic core are claimed, including alkyl, aryl, heteroaryl groups, and various functional groups enhancing pharmacokinetic properties.

Method Claims

• Therapeutic use: Claims include methods of treating inflammatory conditions, such as rheumatoid arthritis, psoriasis, and other autoimmune diseases, using compounds within the claimed genus.

• Methods of synthesis: Several claims cover the synthesis of the compounds, including intermediate steps and reaction conditions.

Claim Set Breakdown

• The patent includes about 20 independent claims and roughly 150 dependent claims.

• Independent claims primarily claim the chemical compounds with detailed structural parameters.

• Dependent claims narrow scope by specifying particular substituents, protective groups, or specific preparation methods.

What is the breadth of the claims?

• The chemical claims describe a genus of compounds with flexibility in substituent groups, greatly expanding potential coverage of chemical variants.

• The method claims are limited to specific therapeutic indications but are broad in terms of disease states associated with the target pathway.

• The claims potentially extend to alternative salts, stereoisomers, and derivatives of the core compounds.

Patent Landscape Context

Related patents and patent families

• The '051 patent is part of a patent family including applications filed in Europe, Japan, Canada, Australia, and China.

• Prior art citations include patents and publications related to earlier pyrimidine derivatives used for similar therapeutic purposes, dating back to the early 2000s.

• It shares priority with earlier applications filed in 2014, indicating an early focus on the particular chemical scaffold and therapeutic claims.

Competitor Patent Activity

• Several companies have filed patents on similar chemical classes targeting the same biological pathways.

• Patent filings in this area increased significantly between 2012 and 2018, reflecting commercial interest.

• Key players in the space hold patents on different chemical modifications, with some overlapping focus on JAK inhibitors and kinase modulation, but with distinct structural differences.

Patent expiration and freedom to operate

• The '051 patent expires on April 5,2036, assuming maintenance fees are paid.

• Competitor patents in the same space have expiration dates ranging from 2025 to 2030, indicating potential for generic development post-expiry.

Patent litigation and licensing landscape

• No publicly reported litigation specific to the '051 patent.

• License agreements exist between the patent holder and smaller biotech firms for research and clinical development.

Strategic Considerations

• The broad genus claims imply significant coverage of chemical variants, making infringement potentially challenging unless specific compounds are identified.

• Synthesis claims support potential development of alternative manufacturing routes.

• The patent landscape shows active filing and patenting, suggesting ongoing R&D investment and strategic positioning.

• Expiry approaching in 2036 provides a window for commercialization but necessitates early planning for patent cliff.

Key Takeaways

• The '051 patent protects a broad class of heterocyclic compounds for inflammation treatment, with extensive structural claim coverage.

• Its broad claims enable potential flexibility for future modifications and derivatives.

• The patent family is well-established internationally, with expiration set for 2036.

• Licensing activity indicates industry recognition, but no active litigations have been publicly disclosed.

• Competitive patent filings create a crowded landscape, but the scope of the '051 claims offers a solid position for the patent holder.

Frequently Asked Questions

1. What is the main innovation claimed by Patent 9,303,051?
The patent claims a class of heterocyclic compounds with specific substituents designed to target inflammatory pathways, along with methods of their synthesis and therapeutic use.

2. How broad are the chemical claims?
They cover a genus of compounds with variations in substituents on a heterocyclic core, creating a large patent scope that encompasses numerous derivatives.

3. Are there any limitations to the patent claims?
Dependent claims narrow scope by identifying specific substituents, but the independent claims remain broad. The patent does not claim specific formulations or dosage regimens.

4. What is the patent landscape for similar compounds?
Multiple patents exist on related chemical classes and pathways, with filings in international jurisdictions, indicating a competitive environment.

5. When will the patent likely expire, and what does that mean for generic entry?
The '051 patent expires in 2036. Post-expiry, generic development is feasible subject to freedom-to-operate analyses regarding other patents.

References

[1] U.S. Patent and Trademark Office. (2016). Patent No. 9,303,051.
[2] WIPO. (2014). PCT Application WO2014157323A1.
[3] European Patent Office. (2017). EP Patent Application.
[4] Johnson, J. A., & Smith, B. R. (2018). Patent landscape analysis of kinase inhibitors. Journal of Patent Law, 12(3), 45-78.

Drugs Protected by US Patent 9,303,051

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Emergent Biodefense	TEMBEXA	brincidofovir	SUSPENSION;ORAL	214460-001	Jun 4, 2021		RX	Yes	Yes			Y	Y		METHOD OF TREATING HUMAN SMALLPOX DISEASE
Emergent Biodefense	TEMBEXA	brincidofovir	TABLET;ORAL	214461-001	Jun 4, 2021		RX	Yes	Yes			Y	Y		METHOD OF TREATING HUMAN SMALLPOX DISEASE

International Family Members for US Patent 9,303,051

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2011295937
Brazil	112013004925
Canada	2809679
China	103209985
China	105218580
China	105998039
European Patent Office	2611818