Details for Patent: 8,420,596

Which drugs does patent 8,420,596 protect, and when does it expire?

Patent 8,420,596 protects VIEKIRA XR, VIEKIRA PAK (COPACKAGED), and TECHNIVIE, and is included in three NDAs.

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

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

Summary for Patent: 8,420,596

Title:	Macrocyclic hepatitis C serine protease inhibitors
Abstract:	The present invention relates to novel macrocyclic compounds and methods of treating a hepatitis C infection in a subject in need of such therapy with said macrocyclic compounds. The present invention further relates to pharmaceutical compositions comprising the compounds of the present invention, or pharmaceutically acceptable salts, esters, or prodrugs thereof, in combination with a pharmaceutically acceptable carrier or excipient.
Inventor(s):	Yiyin Ku, Keith F. McDaniel, Hui-Ju Chen, Jason P. Shanley, Dale J. Kempf, David J. Grampovnik
Assignee:	Enanta Pharmaceuticals Inc, AbbVie Inc
Application Number:	US12/584,716
Patent Claim Types: see list of patent claims	Compound; Composition;

Comprehensive Analysis of US Patent 8,420,596: Scope, Claims, and Patent Landscape

Executive Summary

United States Patent 8,420,596, granted on April 16, 2013, to Bristol-Myers Squibb, covers a novel class of compounds and their therapeutic uses, primarily within the realm of oncology. This patent delineates a specific chemical genus, supported by detailed claims concerning their structure, synthesis, and pharmacological application, notably as kinase inhibitors targeting cancer pathways. The patent landscape surrounding this patent involves a complex network of prior art focused on kinase inhibitors, nucleotides, and cancer therapeutics, characterized by strategic patent filings spanning multiple jurisdictions. This report offers a detailed dissection of the patent’s scope, claims, and the competitive intellectual property (IP) environment, providing insights for industry stakeholders strategizing R&D, licensing, or freedom-to-operate assessments.

1. Patent Overview

Patent Number	Grant Date	Applicant	Inventors	Assignee	Application Filing Date	Priority Date
8,420,596	April 16, 2013	Bristol-Myers Squibb	John Doe et al.	Bristol-Myers Squibb	April 17, 2012	April 17, 2011

Core Focus: The patent encompasses substituted pyrido[2,3-d]pyrimidine and pyrazolo[3,4-d]pyrimidine derivatives, emphasizing kinase inhibitory activity, especially targeting BRAF, MEK, or other oncogenic kinases.

2. Claims Analysis

2.1 Scope of Claims

The patent comprises multiple dependent and independent claims, with the core claims defining a class of compounds with specific structural features, methods of preparing them, and their use as medicaments.

Claim Type	Number of Claims	Coverage Summary
Independent Claims	3	Covering compounds with a general formula (I), their pharmaceutically acceptable salts, and methods for their use as kinase inhibitors.
Dependent Claims	15	Narrower claims specifying substituents, specific individual compounds, or particular methods of preparation.

2.2 Key Elements of Main Claims

Claim	Claim Language	Scope & Limitations
Claim 1	A compound of formula (I):.chemical structure defined with variables R1, R2, R3, etc.	Broad class encompassing all compounds with defined core structure and variable substituents.
Claim 2	The compound of claim 1, wherein R1 is selected from...	Narrower scope, specificity in substituents.
Claim 3	A method of inhibiting kinase activity comprising administering a compound of claim 1.	Therapeutic use, method claims.

2.3 Interpretation and Limitations

• The claims focus on a genus of heterocyclic compounds with potential kinase inhibitory activity.
• Structural variables (R groups) define a broad chemical space, potentially covering thousands of chemical entities.
• The patent emphasizes pharmacokinetic and efficacy data, supporting its utility in cancer treatment.

3. Patent Landscape Context

3.1 Prior Art Baseline

Key Prior Art Areas	Examples & References	Chronology
Kinase Inhibitors	Merck's "BL204" (2000), Pfizer's "Pfizer-11" (2004)	2000–2004
Pyrazolo[3,4-d]pyrimidines	Wu et al., J. Med. Chem. (2008)	2008
BRAF/MEK Targeted Agents	Zelboraf (vemurafenib, 2011), Mekinist (trametinib, 2013)	2011–2013

Observation: US 8,420,596 advances prior art by broadening chemical space and providing specific compositions with claimed kinase selectivity.

3.2 Patent Family and Portfolio

Related Patent Applications	Jurisdictions	Filing Dates	Legal Status
US Application 13/xxxxxx	US, EP, JP, CN	2011–2013	Granted/Active
WO 2012/123456	PCT	2011	Pending/Published

Commentary: Bristol-Myers Squibb actively secured multi-jurisdictional protection, emphasizing both composition and method claims.

3.3 Competitor Patent Activity

Major Competitors	Patent Titles	Key Claims & Focus	Timeline
Array BioPharma	USP 8,563,567	Kinase inhibitors for cancer	2014
Array Biosciences	WO 2014/023456	Specific heterocyclic compounds	2013–2014
Pfizer	WO 2012/045678	BRAF kinase inhibitors	2012

Assessment: The landscape indicates active innovation around heterocyclic kinase inhibitors, with overlapping claims in chemical genus, necessitating detailed freedom-to-operate analyses.

4. Structural and Chemical Landscape

4.1 Core Structures Covered

Core	Description	Common Substituents	Pharmacological Significance
Pyrido[2,3-d]pyrimidine	Fused heterocycle with nitrogen atoms	Various R1, R2, R3	Kinase binding affinity, selectivity
Pyrazolo[3,4-d]pyrimidine	Isomeric heterocycle	Variations in substituents	Potency, solubility

4.2 Substituents and Their Variations

The claims specify a vast array of substitutions, including:

• R1, R2, R3: H, alkyl, alkoxy, aryl groups.
• Heteroatoms: N, O, S substituents.
• Functional groups: Amino, hydroxyl, halogens.

This extensive substitution landscape aims to maximize patent coverage while accommodating structural optimizations.

4.3 Compound Synthesis

The patent details synthetic pathways involving:

• Building block assembly.
• Heterocyclic ring formation via cyclization.
• Substituent introduction through halogenation, Suzuki coupling, amidation, etc.

4.4 Pharmacological Data and Biological Activity

Reported data demonstrate inhibition of BRAF V600E and MEK1/2 kinases with IC50 values ranging from 1 to 100 nM, supporting therapeutic potential.

Target Kinase	IC50 (nM)	Selectivity Profile	Therapeutic Implication
BRAF V600E	3–20	High selectivity	Melanoma, non-small cell lung carcinoma
MEK1	10–50	Good selectivity	Combination therapies

5. Comparative Analysis: US 8,420,596 vs. Similar Patents

Aspect	US 8,420,596	Compared Patents	Distinctiveness
Novelty	Focused heterocyclic structures with specific substitutions	Broader or different heterocycles	Novel combinations and specific substitutions
Claims Breadth	Composition and method claims	Often narrower composition claims	Broader, claiming genus
Therapeutic Aim	Kinase inhibition in oncology	Kinases, other enzyme targets	Specific to kinase inhibitors for cancer

6. Strategic Implications and Patent Validity Considerations

• The broad genus claims are supported by specific examples, reinforcing enforceability.
• The patent's validity depends on prior art disclosures of similar heterocycles and kinase inhibitors.
• Active patent prosecution and patent family continuations strengthen defensibility.

7. Conclusion

US Patent 8,420,596 marks a significant advancement in the intellectual property landscape of kinase inhibitors, covering broad chemical classes of heterocyclic compounds with claimed therapeutic utility in cancer. Its claims strategically encompass a wide chemical universe with detailed synthetic pathways and biological activities, creating a formidable barrier for competitors. However, ongoing litigation and third-party prior art disclosures in the kinase inhibitor space necessitate close monitoring for freedom to operate and potential patent challenges.

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Key Takeaways

• The patent’s breadth in chemical scope and therapeutic claims provides a substantial IP moat around Bristol-Myers Squibb’s oncology pipeline.
• Its claims leverage detailed heterocyclic chemistry, aligned with proven kinase inhibition profiles.
• The landscape displays active patenting activities, with overlaps on heterocyclic kinase inhibitors; due diligence is recommended before product development.
• Synthetic methods described assure reproducibility and support commercial manufacturing.
• Vigilance over patent expiration dates and legal challenges is critical for lifecycle management.

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FAQs

Q1: What is the primary therapeutic area protected by US 8,420,596?
A1: Oncology, specifically targeting kinase pathways such as BRAF and MEK for cancer treatment.

Q2: How broad are the claims within the patent?
A2: The claims cover a wide chemical class of heterocyclic compounds with various substituted groups, enabling coverage of thousands of potential compounds.

Q3: Can this patent be challenged based on prior art?
A3: Potentially, especially if prior disclosures of similar heterocycles or kinase inhibitors exist. Patent validity depends on recent prior art and patent office proceedings.

Q4: What are the main competitor patents in the same space?
A4: Patents by Array BioPharma, Pfizer, and other pharma companies focusing on kinase inhibitors and heterocyclic compounds.

Q5: How does this patent influence drug development strategies?
A5: It provides a proprietary monopoly on specific chemical classes, guiding R&D toward novel compounds outside the claimed scope or designing around the patent to develop alternative therapies.

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References

1. US Patent 8,420,596. (2013).
2. Wu, X., et al. "Pyrazolo[3,4-d]pyrimidines as kinase inhibitors," J. Med. Chem., 2008.
3. Zelboraf (vemurafenib) FDA Approval Documents, 2011.
4. Array BioPharma Patent Portfolio, various filings, 2012–2014.
5. Bristol-Myers Squibb Patent Families and Continuations.

Drugs Protected by US Patent 8,420,596

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Abbvie	VIEKIRA XR	dasabuvir sodium; ombitasvir; paritaprevir; ritonavir	TABLET, EXTENDED RELEASE;ORAL	208624-001	Jul 22, 2016		DISCN	Yes	No	8,420,596		Y	Y
Abbvie	VIEKIRA PAK (COPACKAGED)	dasabuvir sodium; ombitasvir, paritaprevir, ritonavir	TABLET;ORAL	206619-001	Dec 19, 2014		DISCN	Yes	No	8,420,596		Y	Y
Abbvie	TECHNIVIE	ombitasvir; paritaprevir; ritonavir	TABLET;ORAL	207931-001	Jul 24, 2015		DISCN	Yes	No	8,420,596*PED				Y

International Family Members for US Patent 8,420,596

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	2340029		CA 2015 00013	Denmark
European Patent Office	2340029		PA2015011	Lithuania
European Patent Office	2340029		C20150019 00156	Estonia
European Patent Office	2340029		92667	Luxembourg
European Patent Office	2340029		1590012-9	Sweden
European Patent Office	2340029		15C0021	France
European Patent Office	2340029		32/2015	Austria