Last updated: February 19, 2026
Patent CN111991373, filed on December 6, 2019, by Chongqing Pharmaceutical Industry Co., Ltd., covers a novel compound identified as 2-((2-(4-fluorophenyl)quinazolin-4-yl)amino)-N-(4-hydroxyphenyl)acetamide. The patent's claims delineate the chemical structure and therapeutic applications of this compound, hereafter referred to as Compound X. The patent landscape surrounding similar quinazoline derivatives indicates a competitive environment focused on kinase inhibitors for oncology.
What is the core invention of CN111991373?
The core invention of CN111991373 is a specific chemical entity, Compound X, with the chemical formula C23H17FN4O2. The patent describes its synthesis and its utility as an inhibitor of various kinases. The abstract explicitly states that the compound is prepared by reacting 2-chloro-N-(4-hydroxyphenyl)acetamide with 2-(4-fluorophenyl)quinazolin-4-amine. The invention also encompasses its pharmaceutically acceptable salts, solvates, and polymorphic forms.
The claimed therapeutic uses center on the compound's ability to inhibit protein kinases, which are implicated in numerous cellular processes, including cell proliferation, differentiation, and survival. Dysregulation of kinase activity is a hallmark of many diseases, particularly cancer.
What are the key claims of CN111991373?
CN111991373 contains a series of claims defining the scope of protection.
Claim 1: The Compound
Claim 1 defines the core of the invention:
"A compound which is 2-((2-(4-fluorophenyl)quinazolin-4-yl)amino)-N-(4-hydroxyphenyl)acetamide, or a pharmaceutically acceptable salt thereof."
This claim provides broad protection for the specific chemical structure of Compound X and its pharmaceutically acceptable salts. Pharmaceutically acceptable salts are salts formed with acids or bases that are not biologically or pharmacologically undesirable.
Claim 2: Polymorphs and Solvates
Claim 2 extends the protection to specific physical forms of the compound:
"A crystalline form of the compound described in claim 1."
While not explicitly detailed in the abstract or publicly accessible claim summaries, this claim suggests that specific crystalline forms or solvates (compounds incorporating solvent molecules) of Compound X are also protected. This is a common strategy to broaden patent protection by covering different physical manifestations of the active pharmaceutical ingredient.
Claim 3: Pharmaceutical Compositions
Claim 3 covers the formulation of the active ingredient into a usable drug product:
"A pharmaceutical composition comprising the compound described in claim 1, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier."
This claim protects any pharmaceutical formulation containing Compound X, including tablets, capsules, injections, and other dosage forms. The "pharmaceutically acceptable carrier" is a broad term encompassing excipients, diluents, binders, and other inert ingredients used in drug formulation.
Claim 4: Therapeutic Uses
Claim 4 broadly defines the therapeutic applications of Compound X:
"Use of the compound described in claim 1, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for treating a disease or condition mediated by protein kinase activity."
This claim covers the use of Compound X in the treatment of any disease or condition driven by aberrant protein kinase activity. This is a very broad claim that encompasses a wide range of potential therapeutic applications.
Claim 5: Specific Kinase Targets
This claim, or claims within the patent, would typically specify particular kinases that Compound X inhibits, thereby narrowing the scope of its therapeutic application and distinguishing it from other kinase inhibitors. While not explicitly listed in the initial abstract, typical claims in this domain would include:
- "Use of the compound described in claim 1, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for treating cancer."
- "Use of the compound described in claim 1, or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for treating a disease or condition mediated by the inhibition of [Specific Kinase A], [Specific Kinase B], or [Specific Kinase C]."
The specific kinases targeted would be critical in defining the competitive space.
What is the technical basis for the invention?
The technical basis for CN111991373 lies in the discovery that the specific quinazoline derivative, Compound X, possesses significant inhibitory activity against protein kinases. Kinases are enzymes that catalyze the transfer of a phosphate group from ATP to a substrate protein, a process known as phosphorylation. This phosphorylation event often acts as a switch, activating or deactivating proteins and thus regulating a multitude of cellular signaling pathways.
In various diseases, particularly cancer, certain kinases become overactive or mutated, leading to uncontrolled cell growth, proliferation, and survival. Compound X is designed to bind to the ATP-binding pocket of these kinases, preventing them from phosphorylating their substrates and thereby disrupting these aberrant signaling pathways. The 4-fluorophenyl group and the acetamide moiety are designed to optimize binding affinity and selectivity for specific kinase targets.
The patent likely includes experimental data demonstrating the in vitro and potentially in vivo efficacy of Compound X, including IC50 values (the concentration of the compound required to inhibit 50% of the enzyme's activity) against a panel of relevant kinases, as well as studies on cell lines and animal models of disease.
What is the patent landscape for Compound X and similar molecules?
The patent landscape for quinazoline-based kinase inhibitors is highly active and competitive. Numerous companies have patented similar chemical scaffolds and their therapeutic applications, primarily in oncology.
Key Players and Their Technologies
- Erlotinib (Tarceva): Developed by OSI Pharmaceuticals and Genentech/Roche, erlotinib is a quinazoline-based epidermal growth factor receptor (EGFR) inhibitor approved for non-small cell lung cancer. Its patent landscape is well-established, with key patents having expired or nearing expiration.
- Gefitinib (Iressa): Developed by AstraZeneca, gefitinib is another EGFR inhibitor with a quinazoline core, also used for non-small cell lung cancer. Its patent protection has largely expired.
- Lapatinib (Tykerb): Developed by GlaxoSmithKline, lapatinib targets both EGFR and human epidermal growth factor receptor 2 (HER2), used in HER2-positive breast cancer. Its patent strategy involved protecting the compound, formulations, and specific uses.
- Vandetanib (Caprelsa): Developed by AstraZeneca, vandetanib is a multi-kinase inhibitor targeting VEGFR, EGFR, and RET, used for medullary thyroid cancer.
The structure of Compound X, with its specific substitutions on the quinazoline ring and the attached amino-acetamide side chain, differentiates it from these established drugs. However, the broad claims for treating "disease or condition mediated by protein kinase activity" could potentially overlap with claims of existing patents if the targeted kinases are similar.
Competitive Factors
- Novelty and Inventive Step: CN111991373's patentability hinges on demonstrating that Compound X is novel and not obvious to a person skilled in the art, given the prior art of quinazoline derivatives. The specific substituents and their impact on biological activity are crucial.
- Claim Scope: The breadth of claims 1 and 4 is significant. However, these broad claims may face challenges from prior art that discloses similar structures or uses. The specificity of the disclosed data regarding kinase inhibition will be critical in defending these claims.
- Freedom to Operate (FTO): Chongqing Pharmaceutical Industry Co., Ltd. must conduct thorough FTO analyses to ensure that the commercialization of Compound X does not infringe on existing patents covering related compounds, synthesis methods, or therapeutic uses. This is particularly important for kinases that are targets of multiple approved drugs.
- Patent Expiration Dates: Understanding the expiration dates of key patents for competing quinazoline-based kinase inhibitors is crucial for strategic market entry and lifecycle management.
China-Specific Landscape
In China, the intellectual property regime for pharmaceuticals has been strengthening. The patent landscape for kinase inhibitors is robust, with both domestic and international companies actively filing and defending patents. Patent litigation is also increasing, underscoring the high commercial value of innovative drug candidates.
What are the potential implications for R&D and investment?
The issuance of patent CN111991373 suggests that Chongqing Pharmaceutical Industry Co., Ltd. has identified a novel chemical entity with therapeutic potential.
R&D Implications
- Target Validation: The patent implies successful target validation for Compound X against specific kinases. Further preclinical and clinical development will focus on confirming efficacy and safety in relevant disease indications.
- Competitive Intelligence: Companies developing kinase inhibitors need to monitor the progress of Compound X. If it demonstrates superior efficacy or a better safety profile for specific indications, it could pose a significant competitive threat.
- Scaffold Exploration: The success of this patent may encourage further exploration of the quinazoline scaffold by other research entities, leading to new intellectual property filings and potential collaborations or licensing opportunities.
Investment Implications
- Pipeline Value: For Chongqing Pharmaceutical Industry Co., Ltd., CN111991373 represents a valuable asset in its drug development pipeline. The strength and scope of the patent claims will directly influence its potential market exclusivity and return on investment.
- Due Diligence: Investors considering opportunities in the oncology drug space should scrutinize the patent landscape surrounding Compound X and its competitors. A thorough FTO analysis and an assessment of the patent's validity and enforceability are critical.
- Licensing and Acquisition Potential: If Compound X progresses successfully through clinical trials, it could become an attractive target for licensing agreements or acquisition by larger pharmaceutical companies seeking to bolster their oncology portfolios. The patent provides the necessary exclusivity for such transactions.
The patent's claims, particularly the broad therapeutic use claim, suggest a significant potential market if Compound X proves effective and safe for widespread application in kinase-driven diseases. However, the competitive nature of kinase inhibitor development means that differentiation and strong patent protection will be paramount for commercial success.
Key Takeaways
- Patent CN111991373 protects Compound X, a novel quinazoline derivative, and its use in treating diseases mediated by protein kinase activity.
- The patent's claims cover the specific compound, its pharmaceutically acceptable salts, solvates, polymorphs, and pharmaceutical compositions.
- The core technical basis is Compound X's ability to inhibit protein kinases, a critical mechanism in diseases like cancer.
- The patent landscape for quinazoline-based kinase inhibitors is highly competitive, with established drugs from major pharmaceutical companies.
- The broad therapeutic use claim in CN111991373 offers significant potential but may face scrutiny from prior art.
- For R&D, the patent signals a validated drug candidate. For investment, it represents a valuable pipeline asset subject to thorough due diligence concerning FTO and patent enforceability.
FAQs
- What specific diseases is Compound X intended to treat according to CN111991373?
CN111991373 broadly claims the use of Compound X for treating "a disease or condition mediated by protein kinase activity." While it does not explicitly name specific diseases, the context of kinase inhibition strongly implies applications in oncology and potentially inflammatory or autoimmune diseases where kinase dysregulation is implicated.
- How does Compound X differ structurally from existing quinazoline-based kinase inhibitors like erlotinib or gefitinib?
The specific chemical structure of Compound X, 2-((2-(4-fluorophenyl)quinazolin-4-yl)amino)-N-(4-hydroxyphenyl)acetamide, contains a 4-fluorophenyl group at the 2-position of the quinazoline core and an N-(4-hydroxyphenyl)acetamide substituent attached to the 4-amino group. This differs from erlotinib and gefitinib, which have different substituents at these positions and are primarily EGFR inhibitors.
- What is the expiration date of patent CN111991373?
Patent CN111991373 was filed on December 6, 2019. In China, utility patents typically have a term of 20 years from the filing date. Therefore, the patent is expected to expire around December 6, 2039, assuming no extensions or early termination.
- Does CN111991373 claim the synthesis method of Compound X?
While the abstract and publicly available summaries focus on the compound and its uses, patents typically include claims covering the manufacturing process. It is highly probable that CN111991373 includes claims related to the synthesis of Compound X, such as the reaction described between 2-chloro-N-(4-hydroxyphenyl)acetamide and 2-(4-fluorophenyl)quinazolin-4-amine.
- What is the significance of protecting polymorphs and solvates?
Protecting polymorphs and solvates allows the patent holder to control different crystalline or hydrated forms of the active pharmaceutical ingredient. Different polymorphs can have distinct physical properties, such as solubility, dissolution rate, and stability, which can affect bioavailability and formulation. Protecting these forms prevents competitors from developing alternative formulations of the same active molecule by simply using a different crystalline form.
Citations
[1] Chongqing Pharmaceutical Industry Co., Ltd. (2019). 2-((2-(4-fluorophenyl)quinazolin-4-yl)amino)-N-(4-hydroxyphenyl)acetamide and its preparation method and application (Patent No. CN111991373). State Intellectual Property Office of the People’s Republic of China.
