United States Patent 8,217,057: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 8,217,057, issued on July 10, 2012, is a significant patent in the field of pharmaceuticals, particularly focusing on protein tyrosine kinase inhibitors (PTKIs). This patent is assigned to Pfizer Inc. and involves the work of inventors Jingrong Jean Cui and Michelle Tran-Dubé. Here, we delve into the scope, claims, and the broader patent landscape surrounding this invention.
Background
Protein tyrosine kinase inhibitors are crucial in the treatment of various cancers and other diseases characterized by abnormal cell growth. These inhibitors target specific kinases involved in signaling pathways that regulate cell division and survival. The patent in question pertains to a specific class of PTKIs, namely polymorphs of a c-MET/HGFR inhibitor.
Scope of the Patent
Invention Overview
The patent describes polymorphs of the compound (R)-3-[1-(2,6-Dichloro-3-fluoro-phenyl)-ethoxy]-5-(1-piperidin-4-yl-1H-pyrazol-4-yl)-pyridin-2-ylamine, which is known as crizotinib. Crizotinib is a potent inhibitor of the c-MET and HGFR (hepatocyte growth factor receptor) kinases, making it useful in the treatment of cancers such as non-small cell lung cancer (NSCLC)[4].
Polymorphs and Their Significance
Polymorphs are different crystalline forms of the same compound, each with distinct physical and chemical properties. The patent claims several polymorphs of crizotinib, which exhibit improved solubility, stability, and physicochemical properties. These characteristics are critical for the development of solid dosage forms, such as capsules and tablets, ensuring better bioavailability and efficacy of the drug[4][5].
Claims of the Patent
Composition Claims
The patent includes claims for the crystalline forms of crizotinib, specifically the free base and its salts. These claims cover the structural and chemical aspects of the polymorphs, including their X-ray powder diffraction (XRPD) patterns, which are used to identify and characterize the different crystalline forms[4].
Method Claims
In addition to the composition claims, the patent also includes method claims for the synthesis and use of these polymorphs. These methods detail the processes for preparing the crystalline forms and their application in treating abnormal cell growth, particularly in cancers[4].
Use Claims
The use claims specify the therapeutic applications of the polymorphs, highlighting their efficacy in treating diseases associated with c-MET and HGFR kinase activity. This includes various types of cancer where these kinases play a significant role in tumor growth and progression[4].
Patent Landscape
Related Patents
The patent landscape surrounding US 8,217,057 includes several related patents that cover various aspects of crizotinib and other PTKIs. For example:
- US 7,858,643: This patent describes aminopyridines and aminopyrazines having PTKI activity, including crizotinib and its salts[2][5].
- US 8,785,632: This patent covers enantiomerically pure aminoheteroaryl compounds, including those with PTKI activity, which are related to the compounds described in US 8,217,057[1][2].
Exclusivity and Patent Expiration
The patent exclusivity for crizotinib, as described in US 8,217,057, is part of a broader exclusivity period granted by the FDA. The patent itself is set to expire on November 6, 2029. Additionally, there are other patents related to crizotinib that have different expiration dates, such as US 7,858,643, which expires on October 8, 2029[2].
Continuation Applications
The patent system allows for continuation applications, which can extend the prosecution time and potentially lead to additional patents. The history of US 8,217,057 involves continuation applications, which is a common practice in patent strategy to secure broader and more robust patent protection[3].
Impact on Pharmaceutical Development
Improved Drug Formulations
The polymorphs described in US 8,217,057 have significantly improved the formulation of crizotinib, enhancing its solubility, stability, and overall pharmacokinetic properties. This has been crucial in developing effective solid dosage forms that ensure consistent and reliable drug delivery[5].
Therapeutic Applications
The therapeutic applications of crizotinib, as outlined in the patent, have been instrumental in treating various cancers. The specificity and potency of crizotinib against c-MET and HGFR kinases make it a valuable asset in oncology treatment regimens.
Industry and Market Implications
Competitive Landscape
The patent landscape around crizotinib and related PTKIs is highly competitive, with multiple pharmaceutical companies involved in developing similar compounds. The expiration of key patents, including those related to crizotinib, will open up opportunities for generic versions, potentially altering the market dynamics[2].
Regulatory Considerations
The FDA's exclusivity periods and the patent system play critical roles in regulating the pharmaceutical market. Understanding these regulatory aspects is essential for companies navigating the development and commercialization of new drugs.
Key Takeaways
- Polymorphs of Crizotinib: The patent describes several polymorphs of crizotinib with improved properties for drug formulation.
- Therapeutic Use: The polymorphs are specifically useful in treating cancers associated with c-MET and HGFR kinase activity.
- Patent Expiration: The patent is set to expire on November 6, 2029, with related patents having different expiration dates.
- Regulatory and Market Impact: The patent and its exclusivity period have significant implications for the development and commercialization of crizotinib and related drugs.
Frequently Asked Questions (FAQs)
What is the main subject of US Patent 8,217,057?
The main subject of US Patent 8,217,057 is the polymorphs of the compound (R)-3-[1-(2,6-Dichloro-3-fluoro-phenyl)-ethoxy]-5-(1-piperidin-4-yl-1H-pyrazol-4-yl)-pyridin-2-ylamine, known as crizotinib.
What are the benefits of the polymorphs described in the patent?
The polymorphs described in the patent exhibit improved solubility, stability, and physicochemical properties, which are crucial for the development of effective solid dosage forms.
What is the therapeutic application of crizotinib?
Crizotinib is used in the treatment of cancers, particularly those associated with c-MET and HGFR kinase activity, such as non-small cell lung cancer (NSCLC).
When does the patent expire?
The patent is set to expire on November 6, 2029.
How does the patent landscape affect the pharmaceutical market?
The patent landscape around crizotinib and related PTKIs influences the competitive dynamics and regulatory environment in the pharmaceutical industry, impacting the development and commercialization of new drugs.
Cited Sources:
- US8785632B2 - Enantiomerically pure aminoheteroaryl compounds as protein kinase inhibitors[1].
- Generic Xalkori Availability - Drugs.com[2].
- Continuation Applications - Duke Law School[3].
- US8217057B2 - Polymorphs of a c-MET/HGFR inhibitor[4].
- Innovations and Patent Trends in the Development of USFDA Approved Protein Kinase Inhibitors - MDPI[5].
