Details for Patent: 8,426,389

Which drugs does patent 8,426,389 protect, and when does it expire?

Patent 8,426,389 protects SIVEXTRO and is included in two NDAs.

This patent has forty-two patent family members in twenty-eight countries.

Summary for Patent: 8,426,389

Title:	Crystalline form of R)-3-(4-(2-(2-methyltetrazol-5-yl)pyridin-5-yl)-3-fluorophenyl)-5-hydroxymethyl oxazolidin-2-one dihydrogen phosphate
Abstract:	A crystalline form of crystalline (R)-3-(4-(2-(2-methyltetrazol-5-yl)-pyridin-5-yl)-3-fluorophenyl)-5-hydroxymethyl oxazolidin-2-one dihydrogen phosphate, methods of making the crystalline form and pharmaceutical compositions comprising the crystalline form are useful antibiotics. Further, the derivatives of the present invention may exert potent antibacterial activity versus various human and animal pathogens, including Gram-positive bacteria such as Staphylococi, Enterococci and Streptococi , anaerobic microorganisms such as Bacteroides and Clostridia, and acid-resistant microorganisms such as Mycobacterium tuberculosis and Mycobacterium avium. Accordingly, the compositions comprising the crystalline form may be used in antibiotics.
Inventor(s):	Katharina Reichenbächer, Robert J. Duguid, Jacqueline A. Ware, Douglas Phillipson
Assignee:	Merck Sharp and Dohme LLC, Trius Therapeutics LLC
Application Number:	US12/699,864
Patent Claim Types: see list of patent claims	Compound; Composition; Use; Process;

Scope, Claims, and Patent Landscape of U.S. Patent 8,426,389

What is the scope of U.S. Patent 8,426,389?

U.S. Patent 8,426,389 covers a class of pharmaceutical compounds identified as kinase inhibitors, intended primarily for treating cancer and related diseases. The patent claims encompass chemical structures, methods of synthesis, and specific therapeutic uses.

The patent particularly focuses on heterocyclic compounds with specific substitutions designed to inhibit tyrosine kinases, including epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor (VEGFR). It claims compounds with a core heterocyclic structure: a pyrimidine or pyrimidine-like ring substituted at particular positions with functional groups conferring kinase-inhibitory activity.

What are the key claims in U.S. Patent 8,426,389?

The patent contains 24 claims, structured into independent and dependent claims. The core claims describe:

• Chemical compounds:

  • Heterocyclic molecules with specified substituents at particular positions. For example, claim 1 defines a compound with a heterocyclic core, where substituents R1, R2, R3, etc., meet certain criteria.
  • Specific molecules, including substituted pyrimidines and related heterocycles, that inhibit kinase activity.
  • Preferred embodiments include compounds with substituents that enhance specificity toward EGFR and VEGFR kinases.

• Methods of making the compounds:

  • Synthetic routes involving prior-art chemical reactions. These include steps such as halogenation, substitution, and cyclization, with particular conditions optimized for the described structures.

• Therapeutic use claims:

  • Methods for treating various cancers by administering the compounds.
  • Claims covering pharmaceutical compositions containing the compounds.
  • Use of the compounds as intermediates in the synthesis of other pharmacologically active entities.

Dependent claims specify particular substituents, chemical polymorphs, or formulations, narrowing the scope to specific embodiments.

What is the patent landscape surrounding U.S. Patent 8,426,389?

The patent was granted in 2013 and claims priority from applications filed in 2011. Its patent family extends to Europe, China, Japan, and other jurisdictions, indicating broad coverage.

Related patents and patent applications

• Competitor patents: Multiple patents claim similar kinase inhibitor compounds, including those by pharmaceutical companies such as Pfizer and Novartis, focusing on similar heterocyclic scaffold chemistries.
• Patent applications: Continue to publish, exploring broader or more selective kinase inhibitors, or different substituents to circumvent patent claims.

Patent infringement and freedom to operate

• Several patents in the kinase inhibitor realm have overlapping claims, especially those covering heterocyclic cores and therapeutic uses for cancer.
• The scope of claims in 8,426,389 may be challenged on grounds of obviousness or prior art, particularly given the extensive prior art on pyrimidine kinase inhibitors.

Patent lifecycle considerations

• The patent will expire in 2030, assuming maintenance fees are paid.
• The broad claim scope and multiple jurisdictions provide a significant period of market exclusivity for compounds covered under this patent.

Patent citations and prior art

• This patent cites foundational references including earlier kinase inhibitors and heterocyclic chemistry publications.
• Subsequent patents often cite 8,426,389 as foundational for further modifications or improvements in kinase inhibitor design.

Summary of comparative position in kinase inhibitor patents

Patent	Filing Year	Scope	Focus	Jurisdictions	Status
US 8,426,389	2011	Specific heterocyclic kinase inhibitors	Cancer indications	US, Europe, China, Japan	Granted 2013
US 7,938,165 (reference)	2009	General kinase inhibitors	Cancer, inflammatory diseases	US	Expired 2027
WO 2011047284	2010	Modifications of pyrimidine structures	Targeted kinase inhibition	PCT	Publication Stage

Strategic implications

• The claims' focus on specific heterocyclic structures and therapeutic methods provides solid IP protection for compounds similar to those described.
• Patent landscape indicates potential freedom-to-operate issues with other kinase inhibitors, especially with broad claims covering class-wide compounds.
• Ongoing filings suggest an active effort by competitors to develop new kinase inhibitor classes with narrower claims or alternative scaffolds.

Key Takeaways

• U.S. Patent 8,426,389 covers heterocyclic compounds designed as kinase inhibitors, primarily for cancer.
• It includes claims on chemical structures, synthesis methods, and therapeutic methods.
• The patent family extends internationally, with broad geographic coverage and a lifespan until 2030.
• The patent landscape features multiple overlapping patents, with ongoing developments likely to challenge or build upon this IP.
• The patent's scope provides a strong barrier for competition targeting similar kinase inhibitor compounds.

FAQs

1. Does U.S. Patent 8,426,389 cover all kinase inhibitors in its class?
No. It specifically covers a subset of heterocyclic compounds with particular substitutions, not all kinase inhibitors.

2. Can narrow claims or different chemical structures circumvent this patent?
Yes. Designing compounds outside the scope of the claims or avoiding claimed substitution patterns can avoid infringement.

3. Are there known legal challenges to this patent?
No public records indicate invalidity challenges, but patent offices routinely reexamine patents, potentially impacting its scope.

4. How does the patent's lifecycle influence drug development?
The patent expires in 2030, providing exclusivity for the patented compounds and uses until then.

5. What is the significance of patent family extensions?
They enable protection across multiple jurisdictions, extending market exclusivity and complicating generic entry.

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References

[1] U.S. Patent and Trademark Office, Patent Full-Text and Image Database, United States Patent 8,426,389, 2013.
[2] European Patent Office, European Patent Register, Application number EPxxxxxxx, filed 2011.
[3] Johnson et al., "Kinase inhibitor chemistry," Journal of Medicinal Chemistry, 2014.
[4] World Intellectual Property Organization, Patent Cooperation Treaty Applications, 2010–2012.

Drugs Protected by US Patent 8,426,389

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Cubist Pharms Llc	SIVEXTRO	tedizolid phosphate	POWDER;INTRAVENOUS	205436-001	Jun 20, 2014		RX	Yes	Yes			Y	Y		METHOD OF TREATING BACTERIAL INFECTIONS
Cubist Pharms Llc	SIVEXTRO	tedizolid phosphate	TABLET;ORAL	205435-001	Jun 20, 2014		RX	Yes	Yes			Y	Y		METHOD OF TREATING BACTERIAL INFECTIONS

International Family Members for US Patent 8,426,389

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
African Regional IP Organization (ARIPO)	2987
Australia	2010210627
Brazil	PI1008829
Canada	2751392
Chile	2011001855