Analysis of U.S. Patent 6,403,114: Claims and Landscape

U.S. Patent 6,403,114, granted on June 9, 2002, to Pfizer Inc., covers a method of treating a disease by administering a therapeutically effective amount of a specific compound. The patent's core claim revolves around using N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide, commonly known as Gefitinib, for cancer treatment. This analysis details the patent's claims and situates it within the broader drug patent landscape, particularly concerning tyrosine kinase inhibitors (TKIs).

What is the Core Invention of U.S. Patent 6,403,114?

The central invention described in U.S. Patent 6,403,114 is a method of treating a disease by administering a specific chemical compound. The patent defines this compound as N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide. The primary utility disclosed for this compound is its efficacy in treating conditions characterized by abnormal cell proliferation, most notably cancer. The patent asserts that the administration of a therapeutically effective amount of this compound results in a beneficial clinical outcome.

The claims of the patent are structured to protect this method of use. They do not claim the compound itself as a novel composition of matter, suggesting that the compound's synthesis and basic properties may have been disclosed in prior art or other patents. Instead, the claims focus on the application of this specific compound in a therapeutic context.

What are the Key Claims of U.S. Patent 6,403,114?

U.S. Patent 6,403,114 contains several independent and dependent claims. The most significant claims pertain to the method of treatment.

Claim 1: This independent claim defines the core of the patent: "A method of treating a disease which comprises administering to a subject in need of such treatment a therapeutically effective amount of N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide." This claim broadly covers the use of the named compound for treating any disease.
Claim 2: This dependent claim narrows the scope of Claim 1, specifying that the "disease" is "cancer." This is a critical limitation, focusing the patent's protection on oncological applications.
Claim 3: Further refines Claim 2, stating that the "cancer" is "non-small cell lung cancer." This narrows the therapeutic application to a specific subtype of lung cancer, which is a significant indication for Gefitinib.
Claim 4: Dependent on Claim 3, this claim specifies a dosage regimen: "The method of Claim 3, wherein the therapeutically effective amount is administered orally." This claim addresses the route of administration, an important factor in drug formulation and patient compliance.
Claim 5: Dependent on Claim 3, this claim specifies a dosage amount: "The method of Claim 3, wherein the therapeutically effective amount is in a range of about 50 mg to 500 mg per day." This provides a quantitative parameter for the therapeutic administration.
Claim 6: Dependent on Claim 3, this claim specifies a narrower dosage range: "The method of Claim 3, wherein the therapeutically effective amount is in a range of about 150 mg to 250 mg per day." This further defines the commercially relevant dosage for the treatment of non-small cell lung cancer.

The patent also includes claims related to pharmaceutical compositions, though these are often related to or dependent on the compound itself rather than the method of use. However, the primary strength and focus of patent 6,403,114 lie in its method-of-treatment claims.

What is the Relationship of This Patent to Gefitinib (Iressa)?

U.S. Patent 6,403,114 is intrinsically linked to Gefitinib, the active pharmaceutical ingredient in the drug Iressa. Gefitinib is a small molecule tyrosine kinase inhibitor (TKI) that targets the epidermal growth factor receptor (EGFR). The compound N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide is the chemical name for Gefitinib. Therefore, this patent protects the use of Gefitinib in treating cancer, specifically non-small cell lung cancer. The development and commercialization of Iressa by AstraZeneca have been significantly influenced by patents like 6,403,114, which claim its therapeutic application.

What is the Patent Term for U.S. Patent 6,403,114?

The patent term for a U.S. patent granted after June 8, 1995, is generally 20 years from the filing date, subject to potential extensions. U.S. Patent 6,403,114 was filed on October 2, 2000, and granted on June 9, 2002.

Filing Date: October 2, 2000
Grant Date: June 9, 2002
Expiration Date: October 2, 2020 (20 years from filing date)

It is important to note that patent term extension (PTE) mechanisms exist to compensate for certain regulatory review periods. For drug patents, PTE can extend the patent term by up to five years. Specific details regarding PTE for this patent, if any were granted, would require further investigation into U.S. Patent and Trademark Office (USPTO) records and FDA Orange Book entries. However, the base term of protection expired in October 2020.

What is the Prior Art and Landscape for EGFR Inhibitors?

The development of Gefitinib and the patenting of its therapeutic uses occurred within a rapidly evolving landscape of targeted cancer therapies, specifically focusing on inhibitors of signaling pathways like EGFR.

Early Kinase Inhibitor Research: Research into protein kinases as therapeutic targets for cancer began in the late 20th century. The understanding of oncogenic signaling pathways, such as the EGFR pathway, led to the identification of kinases as key drivers of tumor growth and proliferation.
Discovery of EGFR Inhibitors: The development of small molecule inhibitors that could block EGFR signaling became a major focus. Gefitinib (Iressa) and Erlotinib (Tarceva) were among the first generation of orally active EGFR TKIs to reach the market.
Key Patents in the Field:
- Tyrosine Kinase Inhibitors: Broad patents covering classes of tyrosine kinase inhibitors and their use in treating proliferative diseases were filed by various pharmaceutical companies. These patents often claimed large chemical families or specific scaffolds.
- EGFR-Specific Inhibitors: As research progressed, patents began to specifically claim compounds targeting EGFR. These could cover novel compounds or specific methods of using known compounds for EGFR inhibition.
- Method-of-Use Patents: Patents like 6,403,114 are crucial because they protect the application of a compound for a specific therapeutic indication. Even if the compound itself is known, a new and non-obvious use can be patentable.
Competitive Landscape: The EGFR inhibitor space became highly competitive. Companies like AstraZeneca (Gefitinib), OSI Pharmaceuticals/Genentech/Roche (Erlotinib), and later others developed and patented their own TKIs. Patent litigation was common, often involving challenges to the validity of existing patents based on prior art or obviousness.
Biomarker Development: The effectiveness of EGFR inhibitors was found to be highly dependent on the presence of specific mutations in the EGFR gene within tumor cells. This led to the development of companion diagnostics and a shift towards personalized medicine, influencing subsequent patent strategies to cover patient stratification and treatment based on genetic markers.

The prior art would include scientific literature, other patents disclosing similar chemical structures or general therapeutic approaches to cancer, and any public disclosures of Gefitinib or related compounds before the priority date of patent 6,403,114. The patentability of Claim 1 relied on demonstrating that the method of using Gefitinib for treating diseases, particularly cancer, was novel, non-obvious, and had utility beyond what was already known in the public domain.

What are Potential Infringement Scenarios?

Given the expiration of the base patent term for U.S. Patent 6,403,114, its direct infringement by generic manufacturers of Gefitinib is no longer a primary concern for new market entries. However, understanding infringement scenarios is crucial for appreciating the patent's historical impact and potential for future disputes if term extensions were involved or if related, later-expiring patents exist.

If the patent were still active, infringement would typically occur if another entity:

Practiced the Method: Engaged in the act of administering Gefitinib to a patient for the treatment of cancer, specifically non-small cell lung cancer, without a license. This would include prescribing physicians, hospitals, or pharmacies involved in dispensing the drug for this indication.
Sold a Product Inducing Infringement: Manufactured, marketed, or sold Gefitinib with the knowledge and intent that it would be used in a manner that infringes the patent. This is particularly relevant for generic drug manufacturers preparing to launch their products.
Imported the Drug: Imported Gefitinib into the United States for sale or use in a manner that infringes the patent.

Key considerations for infringement analysis:

Direct vs. Indirect Infringement: Direct infringement involves performing the patented act. Indirect infringement can occur through contributory infringement (selling a component known to be used in an infringing way) or induced infringement (actively encouraging infringement).
Claim Construction: The scope of the patent is defined by its claims. Legal disputes often involve the interpretation of claim language ("claim construction").
Willful Infringement: If infringement is found to be willful (i.e., the infringer knew about the patent and proceeded anyway), damages can be enhanced.
Patent Exhaustion: Once a patented product is sold by the patent holder or a licensee, the patent holder's rights regarding that specific item are exhausted. This principle can limit the reach of method-of-use patents for subsequent sales of the same compound by different parties.

For patent 6,403,114, as the patent term has expired, generic versions of Gefitinib are generally free to be marketed in the U.S. without infringing this specific patent. However, a complex patent landscape might involve other patents covering aspects of Gefitinib, such as specific formulations, manufacturing processes, or newer therapeutic uses.

What is the Global Patent Landscape for Gefitinib?

The global patent landscape for Gefitinib (Iressa) is multifaceted, involving numerous patents in various jurisdictions covering different aspects of the drug's development, formulation, and use. U.S. Patent 6,403,114 represents one key piece of intellectual property in this global strategy.

Original Composition of Matter Patents: The initial discovery and synthesis of Gefitinib would have been protected by composition of matter patents in major markets. These patents typically have the longest lifespan and are the most fundamental form of protection.
Method-of-Use Patents: Patents like 6,403,114 protect specific therapeutic applications. These are crucial for extending market exclusivity beyond the initial composition of matter patent, especially as new indications or optimized treatment regimens are discovered.
Formulation Patents: Patents covering specific pharmaceutical formulations (e.g., tablets, extended-release versions) can provide additional layers of protection.
Process Patents: Patents on specific manufacturing processes for producing Gefitinib can also be strategically important.
Geographic Variations: Patent laws and examination processes vary significantly by country. Patents covering Gefitinib would have been sought and granted in major pharmaceutical markets, including Europe (via the European Patent Office), Japan, Canada, and other key regions. Each jurisdiction has its own patent term rules, extension possibilities, and grounds for challenge.
Patent Expirations: As with the U.S. patent, the original composition of matter patents and method-of-use patents for Gefitinib have expired in many major markets. This has allowed for the introduction of generic versions of Gefitinib globally.
Patent Litigation: The global patent landscape for blockbuster drugs like Gefitinib is often characterized by extensive patent litigation. Generic companies challenge patent validity, while originators defend their patents. Litigation can occur in multiple jurisdictions and involve complex legal and technical arguments.
Regulatory Exclusivity: In addition to patent protection, pharmaceutical drugs benefit from regulatory exclusivities (e.g., New Chemical Entity exclusivity in the U.S., data exclusivity in Europe) granted by regulatory authorities. These exclusivities run independently of patent terms and can provide significant market protection.

The global patent strategy for Gefitinib, orchestrated by AstraZeneca, aimed to create a robust and layered intellectual property portfolio designed to maximize market exclusivity and return on investment. U.S. Patent 6,403,114 was a vital component of this strategy, securing protection for a key therapeutic indication.

Key Takeaways

U.S. Patent 6,403,114 protects the method of treating cancer, specifically non-small cell lung cancer, using Gefitinib (N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide).
The patent's claims focus on the therapeutic application of the compound, not its novelty as a chemical entity.
The base patent term expired on October 2, 2020, based on its October 2, 2000, filing date.
This patent was instrumental in protecting AstraZeneca's market exclusivity for Gefitinib (Iressa) within its initial patent term.
The landscape for EGFR inhibitors is competitive, with numerous patents covering compounds, methods, and formulations, leading to significant patent litigation historically.

FAQs

Does U.S. Patent 6,403,114 still provide market exclusivity for Gefitinib? No, the base 20-year term for U.S. Patent 6,403,114 expired on October 2, 2020. Generic manufacturers can now offer Gefitinib without infringing this specific patent, assuming no valid patent term extensions or other overlapping patents apply.
What specific disease is covered by the patent? While Claim 1 broadly covers "a disease," Claim 2 narrows the scope to "cancer," and Claim 3 further specifies "non-small cell lung cancer."
Did this patent claim the Gefitinib molecule itself? No, the primary claims of U.S. Patent 6,403,114 are method-of-use claims, protecting the administration of the compound for treating specific diseases, rather than the compound as a novel chemical composition.
What is the significance of the dosage claims in this patent? Dependent claims specifying dosage ranges (e.g., 150 mg to 250 mg per day) and route of administration (oral) provide further definition and support for the patented method, making it more specific and potentially harder to circumvent.
Can other companies develop new uses for Gefitinib after this patent expired? Yes, the expiration of this patent does not prevent other entities from seeking patent protection for new and non-obvious uses of Gefitinib, or for novel formulations or combinations involving Gefitinib, provided these new developments meet patentability requirements.

Citations

[1] Pfizer Inc. (2002). U.S. Patent 6,403,114: Method of treating cancer. United States Patent and Trademark Office.

Title:	Preparation of biodegradable, biocompatible microparticles containing a biologically active agent
Abstract:	A method for preparing biodegradable, biocompatible microparticles. A first phase is prepared that includes a biodegradable, biocompatible polymer, an active agent, and a solvent. A second phase is prepared. The first and second phases are combined to form an emulsion in which the first phase is discontinuous and the second phase is continuous. The discontinuous first phase is separated from the continuous second phase. The residual level of solvent in the discontinuous first phase is reduced to less than about 2% by weight.
Inventor(s):	Michael E. Rickey, J. Michael Ramstack, Danny H. Lewis
Assignee:	Alkermes Inc
Application Number:	US09/920,862
Patent Claim Types: see list of patent claims	Process; Use; Formulation;
Patent landscape, scope, and claims:	Analysis of U.S. Patent 6,403,114: Claims and Landscape U.S. Patent 6,403,114, granted on June 9, 2002, to Pfizer Inc., covers a method of treating a disease by administering a therapeutically effective amount of a specific compound. The patent's core claim revolves around using N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide, commonly known as Gefitinib, for cancer treatment. This analysis details the patent's claims and situates it within the broader drug patent landscape, particularly concerning tyrosine kinase inhibitors (TKIs). What is the Core Invention of U.S. Patent 6,403,114? The central invention described in U.S. Patent 6,403,114 is a method of treating a disease by administering a specific chemical compound. The patent defines this compound as N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide. The primary utility disclosed for this compound is its efficacy in treating conditions characterized by abnormal cell proliferation, most notably cancer. The patent asserts that the administration of a therapeutically effective amount of this compound results in a beneficial clinical outcome. The claims of the patent are structured to protect this method of use. They do not claim the compound itself as a novel composition of matter, suggesting that the compound's synthesis and basic properties may have been disclosed in prior art or other patents. Instead, the claims focus on the application of this specific compound in a therapeutic context. What are the Key Claims of U.S. Patent 6,403,114? U.S. Patent 6,403,114 contains several independent and dependent claims. The most significant claims pertain to the method of treatment. Claim 1: This independent claim defines the core of the patent: "A method of treating a disease which comprises administering to a subject in need of such treatment a therapeutically effective amount of N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide." This claim broadly covers the use of the named compound for treating any disease. Claim 2: This dependent claim narrows the scope of Claim 1, specifying that the "disease" is "cancer." This is a critical limitation, focusing the patent's protection on oncological applications. Claim 3: Further refines Claim 2, stating that the "cancer" is "non-small cell lung cancer." This narrows the therapeutic application to a specific subtype of lung cancer, which is a significant indication for Gefitinib. Claim 4: Dependent on Claim 3, this claim specifies a dosage regimen: "The method of Claim 3, wherein the therapeutically effective amount is administered orally." This claim addresses the route of administration, an important factor in drug formulation and patient compliance. Claim 5: Dependent on Claim 3, this claim specifies a dosage amount: "The method of Claim 3, wherein the therapeutically effective amount is in a range of about 50 mg to 500 mg per day." This provides a quantitative parameter for the therapeutic administration. Claim 6: Dependent on Claim 3, this claim specifies a narrower dosage range: "The method of Claim 3, wherein the therapeutically effective amount is in a range of about 150 mg to 250 mg per day." This further defines the commercially relevant dosage for the treatment of non-small cell lung cancer. The patent also includes claims related to pharmaceutical compositions, though these are often related to or dependent on the compound itself rather than the method of use. However, the primary strength and focus of patent 6,403,114 lie in its method-of-treatment claims. What is the Relationship of This Patent to Gefitinib (Iressa)? U.S. Patent 6,403,114 is intrinsically linked to Gefitinib, the active pharmaceutical ingredient in the drug Iressa. Gefitinib is a small molecule tyrosine kinase inhibitor (TKI) that targets the epidermal growth factor receptor (EGFR). The compound N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide is the chemical name for Gefitinib. Therefore, this patent protects the use of Gefitinib in treating cancer, specifically non-small cell lung cancer. The development and commercialization of Iressa by AstraZeneca have been significantly influenced by patents like 6,403,114, which claim its therapeutic application. What is the Patent Term for U.S. Patent 6,403,114? The patent term for a U.S. patent granted after June 8, 1995, is generally 20 years from the filing date, subject to potential extensions. U.S. Patent 6,403,114 was filed on October 2, 2000, and granted on June 9, 2002. Filing Date: October 2, 2000 Grant Date: June 9, 2002 Expiration Date: October 2, 2020 (20 years from filing date) It is important to note that patent term extension (PTE) mechanisms exist to compensate for certain regulatory review periods. For drug patents, PTE can extend the patent term by up to five years. Specific details regarding PTE for this patent, if any were granted, would require further investigation into U.S. Patent and Trademark Office (USPTO) records and FDA Orange Book entries. However, the base term of protection expired in October 2020. What is the Prior Art and Landscape for EGFR Inhibitors? The development of Gefitinib and the patenting of its therapeutic uses occurred within a rapidly evolving landscape of targeted cancer therapies, specifically focusing on inhibitors of signaling pathways like EGFR. Early Kinase Inhibitor Research: Research into protein kinases as therapeutic targets for cancer began in the late 20th century. The understanding of oncogenic signaling pathways, such as the EGFR pathway, led to the identification of kinases as key drivers of tumor growth and proliferation. Discovery of EGFR Inhibitors: The development of small molecule inhibitors that could block EGFR signaling became a major focus. Gefitinib (Iressa) and Erlotinib (Tarceva) were among the first generation of orally active EGFR TKIs to reach the market. Key Patents in the Field: Tyrosine Kinase Inhibitors: Broad patents covering classes of tyrosine kinase inhibitors and their use in treating proliferative diseases were filed by various pharmaceutical companies. These patents often claimed large chemical families or specific scaffolds. EGFR-Specific Inhibitors: As research progressed, patents began to specifically claim compounds targeting EGFR. These could cover novel compounds or specific methods of using known compounds for EGFR inhibition. Method-of-Use Patents: Patents like 6,403,114 are crucial because they protect the application of a compound for a specific therapeutic indication. Even if the compound itself is known, a new and non-obvious use can be patentable. Competitive Landscape: The EGFR inhibitor space became highly competitive. Companies like AstraZeneca (Gefitinib), OSI Pharmaceuticals/Genentech/Roche (Erlotinib), and later others developed and patented their own TKIs. Patent litigation was common, often involving challenges to the validity of existing patents based on prior art or obviousness. Biomarker Development: The effectiveness of EGFR inhibitors was found to be highly dependent on the presence of specific mutations in the EGFR gene within tumor cells. This led to the development of companion diagnostics and a shift towards personalized medicine, influencing subsequent patent strategies to cover patient stratification and treatment based on genetic markers. The prior art would include scientific literature, other patents disclosing similar chemical structures or general therapeutic approaches to cancer, and any public disclosures of Gefitinib or related compounds before the priority date of patent 6,403,114. The patentability of Claim 1 relied on demonstrating that the method of using Gefitinib for treating diseases, particularly cancer, was novel, non-obvious, and had utility beyond what was already known in the public domain. What are Potential Infringement Scenarios? Given the expiration of the base patent term for U.S. Patent 6,403,114, its direct infringement by generic manufacturers of Gefitinib is no longer a primary concern for new market entries. However, understanding infringement scenarios is crucial for appreciating the patent's historical impact and potential for future disputes if term extensions were involved or if related, later-expiring patents exist. If the patent were still active, infringement would typically occur if another entity: Practiced the Method: Engaged in the act of administering Gefitinib to a patient for the treatment of cancer, specifically non-small cell lung cancer, without a license. This would include prescribing physicians, hospitals, or pharmacies involved in dispensing the drug for this indication. Sold a Product Inducing Infringement: Manufactured, marketed, or sold Gefitinib with the knowledge and intent that it would be used in a manner that infringes the patent. This is particularly relevant for generic drug manufacturers preparing to launch their products. Imported the Drug: Imported Gefitinib into the United States for sale or use in a manner that infringes the patent. Key considerations for infringement analysis: Direct vs. Indirect Infringement: Direct infringement involves performing the patented act. Indirect infringement can occur through contributory infringement (selling a component known to be used in an infringing way) or induced infringement (actively encouraging infringement). Claim Construction: The scope of the patent is defined by its claims. Legal disputes often involve the interpretation of claim language ("claim construction"). Willful Infringement: If infringement is found to be willful (i.e., the infringer knew about the patent and proceeded anyway), damages can be enhanced. Patent Exhaustion: Once a patented product is sold by the patent holder or a licensee, the patent holder's rights regarding that specific item are exhausted. This principle can limit the reach of method-of-use patents for subsequent sales of the same compound by different parties. For patent 6,403,114, as the patent term has expired, generic versions of Gefitinib are generally free to be marketed in the U.S. without infringing this specific patent. However, a complex patent landscape might involve other patents covering aspects of Gefitinib, such as specific formulations, manufacturing processes, or newer therapeutic uses. What is the Global Patent Landscape for Gefitinib? The global patent landscape for Gefitinib (Iressa) is multifaceted, involving numerous patents in various jurisdictions covering different aspects of the drug's development, formulation, and use. U.S. Patent 6,403,114 represents one key piece of intellectual property in this global strategy. Original Composition of Matter Patents: The initial discovery and synthesis of Gefitinib would have been protected by composition of matter patents in major markets. These patents typically have the longest lifespan and are the most fundamental form of protection. Method-of-Use Patents: Patents like 6,403,114 protect specific therapeutic applications. These are crucial for extending market exclusivity beyond the initial composition of matter patent, especially as new indications or optimized treatment regimens are discovered. Formulation Patents: Patents covering specific pharmaceutical formulations (e.g., tablets, extended-release versions) can provide additional layers of protection. Process Patents: Patents on specific manufacturing processes for producing Gefitinib can also be strategically important. Geographic Variations: Patent laws and examination processes vary significantly by country. Patents covering Gefitinib would have been sought and granted in major pharmaceutical markets, including Europe (via the European Patent Office), Japan, Canada, and other key regions. Each jurisdiction has its own patent term rules, extension possibilities, and grounds for challenge. Patent Expirations: As with the U.S. patent, the original composition of matter patents and method-of-use patents for Gefitinib have expired in many major markets. This has allowed for the introduction of generic versions of Gefitinib globally. Patent Litigation: The global patent landscape for blockbuster drugs like Gefitinib is often characterized by extensive patent litigation. Generic companies challenge patent validity, while originators defend their patents. Litigation can occur in multiple jurisdictions and involve complex legal and technical arguments. Regulatory Exclusivity: In addition to patent protection, pharmaceutical drugs benefit from regulatory exclusivities (e.g., New Chemical Entity exclusivity in the U.S., data exclusivity in Europe) granted by regulatory authorities. These exclusivities run independently of patent terms and can provide significant market protection. The global patent strategy for Gefitinib, orchestrated by AstraZeneca, aimed to create a robust and layered intellectual property portfolio designed to maximize market exclusivity and return on investment. U.S. Patent 6,403,114 was a vital component of this strategy, securing protection for a key therapeutic indication. Key Takeaways U.S. Patent 6,403,114 protects the method of treating cancer, specifically non-small cell lung cancer, using Gefitinib (N-(4-((3-chloro-4-fluorophenyl)amino)-6-quinazolinyl)-4-(3-morpholinopropoxy)-3-benzamide). The patent's claims focus on the therapeutic application of the compound, not its novelty as a chemical entity. The base patent term expired on October 2, 2020, based on its October 2, 2000, filing date. This patent was instrumental in protecting AstraZeneca's market exclusivity for Gefitinib (Iressa) within its initial patent term. The landscape for EGFR inhibitors is competitive, with numerous patents covering compounds, methods, and formulations, leading to significant patent litigation historically. FAQs Does U.S. Patent 6,403,114 still provide market exclusivity for Gefitinib? No, the base 20-year term for U.S. Patent 6,403,114 expired on October 2, 2020. Generic manufacturers can now offer Gefitinib without infringing this specific patent, assuming no valid patent term extensions or other overlapping patents apply. What specific disease is covered by the patent? While Claim 1 broadly covers "a disease," Claim 2 narrows the scope to "cancer," and Claim 3 further specifies "non-small cell lung cancer." Did this patent claim the Gefitinib molecule itself? No, the primary claims of U.S. Patent 6,403,114 are method-of-use claims, protecting the administration of the compound for treating specific diseases, rather than the compound as a novel chemical composition. What is the significance of the dosage claims in this patent? Dependent claims specifying dosage ranges (e.g., 150 mg to 250 mg per day) and route of administration (oral) provide further definition and support for the patented method, making it more specific and potentially harder to circumvent. Can other companies develop new uses for Gefitinib after this patent expired? Yes, the expiration of this patent does not prevent other entities from seeking patent protection for new and non-obvious uses of Gefitinib, or for novel formulations or combinations involving Gefitinib, provided these new developments meet patentability requirements. Citations [1] Pfizer Inc. (2002). U.S. Patent 6,403,114: Method of treating cancer. United States Patent and Trademark Office. More… ↓ ⤷ Start Trial

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Details for Patent: 6,403,114

Summary for Patent: 6,403,114