Detailed Analysis of the Scope and Claims of United States Patent 10,723,730
Introduction
United States Patent 10,723,730, titled "Solid Forms of a Selective CDK4/6 Inhibitor," is a significant patent held by Pfizer Inc. This patent is crucial in the pharmaceutical industry, particularly in the development and manufacture of palbociclib, a drug used in the treatment of certain types of breast cancer.
Background
The patent was granted on July 28, 2020, and is a continuation of earlier patent applications, including U.S. patent application Ser. No. 14/769,038 and PCT/IB2014/058865[1].
Invention Overview
The patent pertains to solid forms of palbociclib, specifically the free base of the compound, which is a potent and selective inhibitor of cyclin-dependent kinases 4 and 6 (CDK4/6). The free base form of palbociclib presented challenges in pharmaceutical development due to its static-prone nature and the formation of small primary particles that agglomerated into large, hard agglomerates. The invention addresses these issues by providing a free base of palbociclib with larger primary particle sizes, demonstrating improved physicochemical and manufacturability properties[1].
Claims
The patent includes several claims that define the scope of the invention:
- Claim 1: This claim describes the free base of palbociclib having a specific particle size distribution, which is critical for its pharmaceutical application.
- Subsequent Claims: These claims further specify the characteristics of the free base, including its crystalline form, particle size range, and methods for preparing the solid forms[1].
Patent Scope
The scope of the patent is defined by the claims and the detailed description provided in the patent document. Here are some key aspects:
- Particle Size: The patent emphasizes the importance of the particle size of the free base, which must be within a specific range to ensure proper dispersion and manufacturability.
- Physicochemical Properties: The invention focuses on improving the physicochemical properties of the free base, making it more suitable for pharmaceutical use.
- Manufacturability: The patent describes methods for preparing the solid forms of palbociclib, ensuring that the final product is stable and can be easily processed into dosage forms[1].
Patent Landscape
The patent landscape surrounding U.S. Patent 10,723,730 is complex and involves several key players and legal proceedings:
- Hatch-Waxman Litigation: The patent is involved in Hatch-Waxman patent infringement suits, where Pfizer alleges that generic manufacturers have infringed on this patent. For example, Pfizer has initiated litigation against Synthon Pharmaceuticals, Inc. in the United States District Courts for the Middle District of North Carolina and the District of Delaware[4][5].
- Orange Book Listings: The patent is listed in the FDA's Approved Drug Products with Therapeutic Equivalence Evaluations (the "Orange Book"), indicating its importance in protecting the intellectual property of Pfizer's drug Ibrance (palbociclib)[4].
- Expiration Dates: The patent is set to expire on February 8, 2034, which is a critical date for generic manufacturers looking to enter the market with their own versions of palbociclib[4].
Legal Implications
The legal implications of this patent are significant:
- Infringement Litigation: The ongoing litigation against generic manufacturers highlights the importance of this patent in protecting Pfizer's market share. The litigation involves paragraph IV certifications by the generic manufacturers, stating that the patents are invalid, unenforceable, or will not be infringed by their products[4].
- Settlements and Injunctions: Similar cases involving other pharmaceutical patents often result in settlements or injunctions that prevent generic manufacturers from entering the market until the patent expires. For example, cases like Celgene Corp. v. Hikma Pharms. USA, Inc. and Vanda Pharms. Inc. v. MSN Pharms. Inc. demonstrate the legal battles surrounding pharmaceutical patents[2].
Industry Impact
The impact of this patent on the pharmaceutical industry is substantial:
- Market Exclusivity: The patent ensures Pfizer's market exclusivity for Ibrance until the patent expires, allowing the company to maintain a significant market share.
- Generic Competition: The expiration of the patent will open the market to generic competition, potentially reducing the cost of the drug and increasing accessibility for patients.
- Research and Development: The protection afforded by this patent incentivizes further research and development in the field of CDK4/6 inhibitors, as companies can recoup their investment through exclusive market rights[4].
Expert Insights
Industry experts emphasize the importance of robust patent protection in the pharmaceutical sector:
"Patents are crucial for pharmaceutical companies to recoup their significant investment in research and development. The protection afforded by patents like U.S. Patent 10,723,730 is essential for maintaining market exclusivity and driving innovation in the industry."[3]
Statistics and Examples
- Patent Maintenance: The maintenance of this patent involves significant costs and legal efforts. For instance, the patent's listing in the Orange Book and the ongoing litigation highlight the resources dedicated to protecting this intellectual property[4].
- Market Value: Ibrance, the drug protected by this patent, has generated billions of dollars in revenue for Pfizer, underscoring the economic importance of this patent[4].
Key Takeaways
- Improved Physicochemical Properties: The patent provides a method for improving the physicochemical properties of palbociclib, making it more suitable for pharmaceutical use.
- Market Exclusivity: The patent ensures Pfizer's market exclusivity for Ibrance until its expiration in 2034.
- Legal Implications: The patent is involved in significant legal proceedings, including Hatch-Waxman litigation against generic manufacturers.
- Industry Impact: The patent affects the pharmaceutical industry by maintaining Pfizer's market share and incentivizing further research and development.
Frequently Asked Questions
Q1: What is the main subject of U.S. Patent 10,723,730?
A1: The main subject is the solid forms of a selective CDK4/6 inhibitor, specifically the free base of palbociclib.
Q2: What challenges did the free base of palbociclib present in pharmaceutical development?
A2: The free base was highly static-prone and formed small primary particles that agglomerated into large, hard agglomerates, making it difficult to disperse and unsuitable for further development.
Q3: How does the patent address these challenges?
A3: The patent provides a method for preparing the free base of palbociclib with larger primary particle sizes, improving its physicochemical and manufacturability properties.
Q4: What is the significance of the patent's listing in the Orange Book?
A4: The listing indicates that the patent is recognized by the FDA as protecting the intellectual property of Pfizer's drug Ibrance, affecting the approval of generic versions.
Q5: When is the patent set to expire?
A5: The patent is set to expire on February 8, 2034.
Cited Sources
- United States Patent and Trademark Office, "Solid Forms of a Selective CDK4/6 Inhibitor," US 10,723,730 B2, July 28, 2020.
- Robins Kaplan LLP, "ANDA Litigation Settlements," Generically Speaking Hatch Waxman Bulletin, Q1 2022.
- SSRN, "Patent Claims and Patent Scope," September 29, 2016.
- U.S. Food and Drug Administration, "ANDA 215570," August 12, 2022.
- FindLaw, "IN RE: PALBOCICLIB ('730) PATENT LITIGATION (No. II)," 2021.
