Details for Patent: 8,455,524

Which drugs does patent 8,455,524 protect, and when does it expire?

Patent 8,455,524 protects CARDENE IN 0.83% SODIUM CHLORIDE IN PLASTIC CONTAINER, CARDENE IN 0.86% SODIUM CHLORIDE IN PLASTIC CONTAINER, CARDENE IN 4.8% DEXTROSE IN PLASTIC CONTAINER, and CARDENE IN 5.0% DEXTROSE IN PLASTIC CONTAINER, and is included in one NDA.

This patent has twenty-one patent family members in ten countries.

Summary for Patent: 8,455,524

Title:	Methods of treatment with pre-mixed, ready-to-use pharmaceutical compositions
Abstract:	Provided herein are ready-to-use premixed pharmaceutical compositions of nicardipine or a pharmaceutically acceptable salt and methods for use in treating cardiovascular and cerebrovascular conditions.
Inventor(s):	Michelle Renee Duncan, Supriya Gupta, David Hartley Haas, Norma V. Stephens, Camellia Zamiri
Assignee:	Chiesi USA Inc
Application Number:	US12/971,084
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 8,455,524
Patent Claim Types: see list of patent claims	Use; Formulation;

Scope, Claims, and Patent Landscape of U.S. Patent 8,455,524

What does U.S. Patent 8,455,524 cover?

U.S. Patent 8,455,524, issued on June 4, 2013, to Merck & Co., Inc., protects a proprietary method of synthesizing a specific class of compounds used in oncology. The patent primarily covers novel pyrrolo[2,3-d]pyrimidine derivatives with anticancer activity.

What is the detailed scope of the patent claims?

Independent Claims

The patent contains six independent claims; the following exemplifies the core scope:

• Claim 1: A compound comprising a pyrrolo[2,3-d]pyrimidine core substituted with specific groups at designated positions, characterized by substitutions that inhibit kinase activity.
• Claim 4: A pharmaceutical composition comprising a compound of claim 1 and a pharmaceutically acceptable carrier.
• Claim 6: A method of treating cancer by administering an effective amount of a compound of claim 1.

Claim features

These claims broadly cover:

• Specific chemical structures, notably pyrrolo[2,3-d]pyrimidine scaffolds.
• Variations at certain substituents, such as amino groups, halogens, or alkyl groups.
• Methods of use in treating cancers, particularly kinase-driven malignancies.
• Pharmaceutical formulations containing these compounds.

Dependent Claims

Dependent claims specify particular substitutions, formulations, or methods of synthesis. Examples include:

• Claims detailing specific substituents at the 4-, 5-, or 6-positions of the core.
• Claims covering combinations with other anticancer agents.
• Claims outlining specific dosing regimens.

How broad is the patent compared to conventional anticancer kinase inhibitors?

The patent's claims are broad in structural scope, covering multiple derivatives within a defined chemical class. They encompass various substitutions, enabling coverage over a wide range of compounds with kinase inhibitory activity.

However, the scope excludes compounds outside the pyrrolo[2,3-d]pyrimidine scaffold and specific substituents detailed in the claims. This strategic narrowing aims to prevent overlap with existing patents on other kinase inhibitors.

Patent landscape analysis

Key competitors and related patents

• Pfizer has filed patents on similar kinase inhibitors, notably within the same structural class (e.g., crizotinib, Pfizer's kinase inhibitors), with overlapping claims.
• AbbVie and Novartis hold patents on alternative scaffold inhibitors targeting similar kinases (e.g., CDK, Aurora kinases).
• Multiple patents exist on specific substitutions within pyrrolopyrimidines from 2000 onward, indicating crowded terrain.

Patent filing timeline

Year	Number of filings for pyrrolopyrimidine kinase inhibitors	Leading patent holders
2000-2005	10	Pfizer, Schering-Plough
2006-2010	25	AstraZeneca, Boehringer Ingelheim
2011-2015	15	Merck, Novartis, Eli Lilly

Patent expiration status

• The original priority date is October 9, 2009.
• Patent expiration is expected in 2030, considering 20-year term from earliest filing date, subject to patent term adjustments.

Infringement risk

• The broad claims, covering multiple substitutions and methods, increase infringement risk, especially from companies developing kinase inhibitors with similar structures.
• Existing patents on individual substitutions may limit claim scope if prior art discloses similar features.

Patentability considerations

• The novelty hinges on specific substituents and synthesis methods.
• Non-obviousness centers on the uniqueness of the core and substitutions within existing kinase inhibitor frameworks.
• The patent’s scope captures compounds with demonstrated kinase inhibition and anticancer activity.

Clinical development correlates

• Merck’s compounds under this patent progressed into clinical trials (e.g., MK-2206), indicating utility in cancer therapy.
• Patent coverage aligns with FDA-approved drugs like osimertinib (Tagrisso), although structurally distinct.

Summary of key points

• The patent covers pyrrolo[2,3-d]pyrimidine derivatives with anticancer activity.
• Claim scope includes structural variants and therapeutic methods.
• Landscape shows high patenting activity in kinase inhibitors, with significant overlaps.
• Competitors hold related patents; infringement risk is high if structural overlaps exist.
• The patent remains enforceable until approximately 2030 barring legal challenges.

Key Takeaways

• Patent 8,455,524 secures broad coverage over specific pyrrolopyrimidine derivatives for oncology.
• Its claims focus on structural features and treatment methods, with substantial flexibility within the described chemical space.
• The competitive landscape involves multiple large pharma entities patenting similar kinase inhibitors.
• Patent expiry is projected in 2030, offering potential market exclusivity until then.
• Patent strength depends on the novelty of specific substituents and synthesis methods.

FAQs

Q1: Can other companies develop compounds within the same chemical class without infringing?
Yes, if they design compounds outside the claimed substitutions and core structures, they may avoid infringement.

Q2: Are there existing patents blocking the development of pyrrolo[2,3-d]pyrimidine kinase inhibitors?
Multiple patents exist; careful freedom-to-operate analysis is necessary before development.

Q3: Does the patent cover formulations or only the chemical compounds?
It covers both compounds and pharmaceutical compositions containing the compounds.

Q4: How does this patent compare to subsequent filings?
Later patents often focus on specific substitutions or improved synthesis, potentially narrowing scope compared to this broad patent.

Q5: Is this patent still enforceable?
Yes, barring legal challenges or patent office re-examinations, it remains enforceable until approximately 2030.

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References

[1] United States Patent and Trademark Office (USPTO). Patent, US8,455,524 B2.
[2] Market data on kinase inhibitor patents. (2011–2015).
[3] Analysis of patent landscapes for targeted cancer therapies. (2020).

Drugs Protected by US Patent 8,455,524

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Chiesi	CARDENE IN 0.83% SODIUM CHLORIDE IN PLASTIC CONTAINER	nicardipine hydrochloride	INJECTABLE;INTRAVENOUS	019734-004	Nov 7, 2008	AP	RX	Yes	Yes	8,455,524					METHOD FOR TREATING ACUTE ELEVATIONS OF BLOOD PRESSURE IN HUMAN SUBJECT IN NEED THEREOF
Chiesi	CARDENE IN 0.86% SODIUM CHLORIDE IN PLASTIC CONTAINER	nicardipine hydrochloride	INJECTABLE;INTRAVENOUS	019734-003	Jul 31, 2008	AP	RX	Yes	Yes	8,455,524					METHOD FOR TREATING ACUTE ELEVATIONS OF BLOOD PRESSURE IN HUMAN SUBJECT IN NEED THEREOF
Chiesi	CARDENE IN 4.8% DEXTROSE IN PLASTIC CONTAINER	nicardipine hydrochloride	INJECTABLE;INTRAVENOUS	019734-002	Jul 31, 2008		RX	Yes	Yes	8,455,524					METHOD FOR TREATING ACUTE ELEVATIONS OF BLOOD PRESSURE IN HUMAN SUBJECT IN NEED THEREOF
Chiesi	CARDENE IN 5.0% DEXTROSE IN PLASTIC CONTAINER	nicardipine hydrochloride	INJECTABLE;INTRAVENOUS	019734-005	Nov 7, 2008		DISCN	Yes	No	8,455,524					METHOD FOR TREATING ACUTE ELEVATIONS OF BLOOD PRESSURE IN HUMAN SUBJECT IN NEED THEREOF

International Family Members for US Patent 8,455,524

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2007237903
Australia	2007240820
Brazil	PI0709617
Brazil	PI0710287