Detailed Analysis of the Scope and Claims of United States Patent 11,091,439
Introduction
United States Patent 11,091,439, titled "Malate Salt of N-(4-{[6,7-bis(methyloxy)quinolin-4-yl]oxy}phenyl)-N′-(4-fluorophenyl)cyclopropane-1,1-dicarboxamide, and Crystalline Forms Thereof for the Treatment of Cancer," is a patent held by Exelixis, Inc. This patent is part of a group known as the Malate Salt Patents, which include U.S. Patent Nos. 11,091,439, 11,091,440, and 11,098,015. Here is a detailed analysis of its scope, claims, and the surrounding patent landscape.
Patent Overview
The patent was issued on August 17, 2021, and it pertains to specific malate salts of a complex organic compound, particularly the (L)-malate salt of N-(4-{[6,7-bis(methyloxy)quinolin-4-yl]oxy}phenyl)-N′-(4-fluorophenyl)cyclopropane-1,1-dicarboxamide. This compound is used in the treatment of cancer, specifically as part of the drug Cabozantinib, marketed under the brand name CABOMETYX®[4][5].
Claims
The patent includes several claims that define the scope of the invention. Here are some key claims:
- Claim 1: This claim describes the malate salt of the specified compound, including its crystalline forms.
- Claim 4: This claim is particularly relevant as it has been asserted in litigation. It specifies the crystalline forms of the malate salt and their use in pharmaceutical compositions for treating cancer[2][5].
Scope of Protection
The scope of protection for this patent is broad and includes:
- Chemical Composition: The specific malate salt of the compound and its crystalline forms.
- Pharmaceutical Use: The use of this compound in treating cancer.
- Manufacturing Processes: Although not explicitly detailed in this patent, related patents like U.S. Patent No. 11,298,349 cover processes for preparing quinoline compounds, which are integral to the synthesis of the patented compound[5].
Patent Landscape
The patent landscape surrounding U.S. Patent 11,091,439 is complex and involves multiple related patents.
- Malate Salt Patents: This group includes U.S. Patent Nos. 11,091,439, 11,091,440, and 11,098,015, all sharing an identical specification. These patents collectively protect the malate salt forms of the compound and their crystalline forms[2][5].
- Related Patents: Other patents, such as U.S. Patent No. 11,298,349, cover processes for preparing quinoline compounds and pharmaceutical compositions containing such compounds. These patents are crucial for understanding the full scope of protection and the manufacturing processes involved[5].
Litigation and Infringement
The patent has been involved in several legal disputes, particularly in the context of generic drug manufacturers.
- ANDA Filings: Generic drug manufacturers like Cipla have filed Abbreviated New Drug Applications (ANDAs) with the FDA, challenging the validity and enforceability of the patents. Cipla's ANDA included a paragraph IV certification, alleging that the patents-in-suit are invalid, unenforceable, and/or will not be infringed by their generic version of CABOMETYX®[5].
- Infringement Claims: Exelixis has asserted claims of infringement against these generic manufacturers. For instance, MSN stipulated to the infringement of the asserted claims of the Malate Salt Patents[2].
Validity and Obviousness
The validity of the patent claims is a subject of dispute. The defendants bear the burden of proving invalidity for lack of written description or obviousness by clear and convincing evidence. The obviousness inquiry under 35 U.S.C. § 103 requires determining whether the differences between the claimed invention and the prior art would have been obvious to a person having ordinary skill in the art[2].
Patent Analytics and Claim Coverage
To manage and analyze the complex patent landscape, companies like Exelixis can use patent analytics tools. These tools help in tracking patents by claims and scope concepts, creating claim charts to review patent coverage, and identifying gaps or opportunities in the current patent portfolio. This approach ensures that all claims and associated scope concepts are accurately analyzed and that future design opportunities are highlighted[3].
Expiration Dates
The patents in question have specific expiration dates:
- U.S. Patent No. 11,091,439 and related Malate Salt Patents expire on January 15, 2030.
- U.S. Patent No. 11,298,349 expires on February 10, 2032[5].
Key Takeaways
- Specific Compound Protection: The patent protects specific malate salts and their crystalline forms used in cancer treatment.
- Litigation Involvement: The patent is involved in ongoing litigation with generic drug manufacturers.
- Complex Patent Landscape: The patent is part of a broader group of related patents covering various aspects of the compound and its manufacturing processes.
- Patent Expiration: The patents have defined expiration dates, impacting the future of generic versions of CABOMETYX®.
FAQs
What is the main subject of U.S. Patent 11,091,439?
The main subject is the malate salt of N-(4-{[6,7-bis(methyloxy)quinolin-4-yl]oxy}phenyl)-N′-(4-fluorophenyl)cyclopropane-1,1-dicarboxamide and its crystalline forms for cancer treatment.
Which drug is protected by this patent?
The drug protected is Cabozantinib, marketed under the brand name CABOMETYX®.
What is the significance of the Malate Salt Patents?
These patents collectively protect the malate salt forms and crystalline forms of the compound, ensuring broad protection for the drug CABOMETYX®.
What legal challenges has this patent faced?
The patent has faced challenges from generic drug manufacturers through ANDA filings and infringement claims.
When do the Malate Salt Patents expire?
The Malate Salt Patents expire on January 15, 2030.
Cited Sources
- United States Patent and Trademark Office, "Malate Salt of N-(4-{[6,7-bis(methyloxy) quinolin-4-yl]oxy}phenyl)-N′-(4-fluorophenyl)cyclopropane-1,1-dicarboxamide, and Crystalline Forms Thereof for the Treatment of Cancer," US11091439B2.
- United States District Court, "22-228.pdf," October 15, 2024.
- Schwegman Lundberg & Woessner, "Patent Analytics | Intellectual Property Law."
- Google Patents, "US11091439B2 - Malate salt of N-(4-{[6,7-bis(methyloxy)-quinolin-4-yl]oxy}phenyl)-N′-(4-fluorophenyl)cyclopropane-1,1-dicarboxamide, and Crystalline Forms Thereof for the Treatment of Cancer."
- RPX Insight, "in the united states district court," May 9, 2024.
