US Patent 10,603,314: Claim Scope, Expiration, and EGFR Inhibitor Patent Landscape
US Patent No. 10,603,314 protects a method of treating gefitinib- or erlotinib-resistant non-small cell lung cancer by administering a daily unit dose of an irreversible EGFR-family inhibitor that covalently binds EGFR cysteine 773 or HER2/erbB-2 cysteine 805. The patent is a narrow, method-of-use patent rather than a broad compound patent. Its commercial value depends on whether a marketed irreversible EGFR inhibitor is administered to patients with the specified resistance phenotype and whether the product label or clinical use supports the claimed regimen.
What does US Patent 10,603,314 claim?
The independent claim requires all of the following elements:
| Claim element |
Required scope |
| Disease |
Non-small cell lung cancer |
| Patient status |
Gefitinib-resistant and/or erlotinib-resistant |
| Treatment |
Daily administration |
| Product |
Pharmaceutical composition with a unit dosage |
| Mechanism |
Irreversible EGFR-family inhibitor |
| Binding site |
EGFR Cys773 or erbB-2/HER2 Cys805 |
| Dependent embodiments |
EKB-569, HKI-357, combination TKI therapy, radiation, and specified administration routes |
Claim 1 is the controlling scope. Claims 2 through 9 narrow the claim by identifying particular inhibitors, binding residues, combination treatments, and delivery routes.
The claim does not cover every irreversible EGFR inhibitor used in lung cancer. It requires covalent binding to one of two specified cysteine residues and treatment of a patient whose NSCLC is resistant to gefitinib and/or erlotinib.
How broad is claim 1 of US 10,603,314?
Claim 1 has a function-and-mechanism structure. It does not name a specific drug. Instead, it covers an irreversible EGFR inhibitor defined by its covalent interaction with:
- Cysteine 773 in the EGFR ligand-binding pocket; or
- Cysteine 805 in the erbB-2/HER2 ligand-binding pocket.
This structure potentially reaches compounds beyond EKB-569 and HKI-357 if they satisfy the binding limitation. The claim therefore has broader chemical scope than claim 2, but the scope remains constrained by the residue-specific covalent-binding requirement.
Disease limitation
The patient must have gefitinib- and/or erlotinib-resistant NSCLC. Resistance is a material limitation, not background context. A product administered to:
- treatment-naive NSCLC patients;
- patients with ordinary EGFR-mutant NSCLC;
- patients who progressed on chemotherapy but not gefitinib or erlotinib; or
- patients with an unrelated tumor type
would not necessarily satisfy claim 1.
The patent does not expressly limit resistance to a particular EGFR mutation, such as T790M. The claim language is broader on mutation status but narrower on the prior treatment history or resistance characterization.
Daily administration
Claim 1 requires administering the composition daily. A once-weekly, intermittent, single-dose, or irregular regimen may fall outside the literal claim unless the dosing schedule is legally characterized as daily under the facts of the case.
Unit dosage limitation
The composition must contain a unit dosage. A conventional tablet, capsule, or other discrete dosage form would likely satisfy this limitation if it contains the relevant inhibitor. The claim does not specify a concentration, tablet strength, excipient, release profile, particle size, or formulation technology.
Covalent-binding limitation
The key technical limitation is covalent binding to EGFR Cys773 or HER2 Cys805. A reversible inhibitor, even one that binds strongly to EGFR, would not meet this limitation. A covalent inhibitor that binds a different residue, or whose covalent interaction is not demonstrated at the claimed residue, presents a stronger non-infringement position.
What do claims 2 through 9 add?
Which drugs are expressly named?
Claim 2 expressly identifies EKB-569 and HKI-357. These compounds are narrow dependent-claim embodiments. The claim set does not establish that either compound has been approved by the FDA or commercially launched as a lung-cancer product.
What are the residue-specific claims?
Claim 3 is limited to covalent binding at EGFR Cys773.
Claim 4 is limited to covalent binding at erbB-2/HER2 Cys805.
Claims 3 and 4 divide the two alternative mechanistic branches in claim 1. They may be useful in infringement analysis because a patent owner would need to establish the relevant target and residue for the accused inhibitor.
What combination treatments are covered?
Claim 5 covers administration with at least one other tyrosine kinase inhibitor. It does not identify the second TKI. The second agent could potentially include an EGFR, HER2, ALK, MET, VEGFR, or other kinase inhibitor, depending on the claim construction and technical facts.
Claim 6 covers administration with radiation. The claim does not specify radiation dose, fractionation, sequencing, or treatment site.
What administration routes are covered?
Claims 7 and 8 list numerous parenteral, local, mucosal, and transdermal routes. Claim 9 separately recites oral administration.
The routes are alternatives. An oral product would generally be assessed under claim 9, while an injectable or locally administered product may be assessed under claim 7. Claims 7 and 8 do not require a particular formulation technology.
What patent does US 10,603,314 protect?
| Item |
Analysis |
| Patent type |
Therapeutic method-of-use patent |
| Core invention |
Treatment of gefitinib- or erlotinib-resistant NSCLC with an irreversible EGFR-family inhibitor |
| Compound coverage |
Indirect and mechanism-based, not a broad chemical composition claim |
| Named compounds |
EKB-569 and HKI-357 |
| Targets |
EGFR and erbB-2/HER2 |
| Key residues |
EGFR Cys773 and HER2 Cys805 |
| Regimen |
Daily administration |
| Formulation limitation |
Unit dosage pharmaceutical composition |
| Combination coverage |
Other TKI and radiation |
| Route coverage |
Oral, injectable, local, mucosal, and transdermal routes |
The claims do not expressly cover:
- the chemical composition of EKB-569 or HKI-357;
- synthesis of either compound;
- a particular tablet or capsule formulation;
- a specific salt, polymorph, crystalline form, or prodrug;
- a specific EGFR mutation;
- a biomarker-testing method;
- a manufacturing process; or
- a broad class of all covalent kinase inhibitors.
Those areas would have to be protected by separate composition, formulation, diagnostic, or manufacturing patents.
When does US Patent 10,603,314 lose exclusivity?
A US utility patent generally expires 20 years from the earliest effective nonprovisional filing date, subject to patent-term adjustment, patent-term extension, terminal disclaimers, and other statutory adjustments under 35 U.S.C. §§ 154 and 156.[2]
The patent number and supplied claims alone do not establish the controlling expiration date. The expiration analysis must be based on the patent’s priority chain, filing history, patent-term adjustment, and any terminal disclaimer recorded by the USPTO. A continuation patent normally does not receive a new 20-year term from its continuation filing date.
The practical diligence conclusion is:
- the patent is an issued US patent;
- its remaining life must be calculated from the earliest effective nonprovisional filing;
- the relevant date may differ from the issue date;
- FDA regulatory exclusivity, if any, would be separate from patent exclusivity.
A patent can remain legally enforceable after the related drug has lost FDA marketing exclusivity, and FDA exclusivity can expire before the patent.
Is US Patent 10,603,314 listed in the Orange Book?
US Patent 10,603,314 is not automatically an Orange Book patent merely because it claims a method of treating cancer. Under FDA rules, a listed patent generally must be associated with an approved drug product and must claim the drug substance, drug product, or an approved method of use.[3]
The practical Orange Book analysis is limited by the apparent status of the compounds identified in the claims:
- EKB-569 is not an FDA-approved commercial lung-cancer product.
- HKI-357 is not an FDA-approved commercial lung-cancer product.
- Neither compound appears to have a conventional FDA-approved reference listed drug against which an ANDA applicant would file a Paragraph IV certification.
- The supplied information does not establish an Orange Book listing for Patent 10,603,314.
If no approved product is covered by the patent, the patent has no ordinary Orange Book-based Paragraph IV enforcement pathway. It could still be asserted in district court against commercial conduct that practices the claims.
What FDA exclusivity applies to the claimed treatment?
The claims do not themselves create FDA exclusivity. Relevant regulatory exclusivity would depend on an approved product and regulatory pathway.
| Regulatory protection |
Relevance to this patent |
| New chemical entity exclusivity |
Potentially relevant only if the active inhibitor were a qualifying new active ingredient |
| New clinical investigation exclusivity |
Could apply to an approved new use supported by qualifying clinical investigations |
| Orphan-drug exclusivity |
Not established by the claim set |
| Pediatric exclusivity |
Depends on FDA action for a specific approved product |
| Biosimilar exclusivity |
Not applicable to small-molecule EKB-569 or HKI-357 |
| Orange Book listing |
Requires an approved product and qualifying listed patent |
EKB-569 and HKI-357 are small molecules. Biosimilar litigation under the Public Health Service Act is therefore not the relevant competitive pathway. Any future competitor would more likely use an ANDA, a 505(b)(2) application, or a full NDA, depending on the product and reference-product facts.
What Paragraph IV challenges could target this patent?
A Paragraph IV challenge requires an approved reference listed drug and an Orange Book-listed patent. If Patent 10,603,314 were listed against an approved product, an ANDA applicant could assert that the patent is:
- invalid;
- unenforceable; or
- not infringed.
Potential non-infringement theories would focus on the claim limitations:
- the patient is not gefitinib- or erlotinib-resistant;
- the indication is not NSCLC;
- the drug does not bind covalently to Cys773 or Cys805;
- the regimen is not daily;
- the product is not a unit dosage composition;
- the accused product is not administered by a claimed route; or
- the use does not include the claimed combination with another TKI or radiation.
Potential invalidity theories would include anticipation, obviousness, written-description deficiency, enablement, indefiniteness, and lack of inventive step. The most important prior-art question is whether the patent’s priority date predates publications describing irreversible EGFR inhibition in gefitinib- or erlotinib-resistant NSCLC.
A generic manufacturer could also pursue a section viii carve-out if the patent covered only a method of use that the generic labeling omits. That route is available only where the remaining approved uses do not practice the patented method.[3]
How strong is the patent estate?
The supplied claims indicate a focused estate with meaningful method-of-use protection but limited standalone product protection.
Strengths
- The independent claim reaches unnamed irreversible inhibitors, not only EKB-569 and HKI-357.
- The residue-specific mechanism provides a technically defined infringement theory.
- The claim addresses a clinically relevant resistance setting.
- Daily treatment and unit dosage requirements map onto ordinary commercial dosing formats.
- Claims 3 and 4 provide separate EGFR and HER2 mechanistic positions.
- Combination claims may reach treatment protocols involving a second TKI or radiation.
Limitations
- The patent does not claim the underlying chemical compounds broadly.
- The patient-resistance limitation narrows the potentially relevant market.
- The covalent-binding requirement may require complex biochemical and structural evidence.
- The claim does not clearly cover all later-generation irreversible EGFR inhibitors unless they bind the claimed residues.
- EKB-569 and HKI-357 do not appear to provide an active commercial product base.
- A generic or competing innovator may avoid infringement through a non-daily regimen, a different patient population, or a product that does not satisfy the residue limitation.
Patent strength is therefore moderate as a targeted use patent and weaker as a barrier to development of the broader irreversible EGFR inhibitor class.
How does this patent compare with later-generation EGFR inhibitor patents?
| Patent category |
Typical protected subject matter |
Relationship to US 10,603,314 |
| Early irreversible EGFR inhibitor patents |
Chemical structures and synthetic routes |
May block or define EKB-569-like compounds |
| Covalent EGFR inhibitor patents |
Broad compound genera, warheads, and kinase-binding scaffolds |
May provide stronger product protection |
| Osimertinib-type patents |
Specific mutant-selective compounds, salts, formulations, and uses |
Often more commercially important than the supplied method claims |
| Formulation patents |
Tablets, amorphous dispersions, solid forms, release profiles |
Separate protection not present in the supplied claims |
| Biomarker patents |
EGFR mutation testing and patient selection |
Could overlap clinically without practicing the same treatment claim |
| Manufacturing patents |
Intermediates, reaction conditions, purification, crystallization |
Address supply-chain barriers rather than treatment use |
A later compound patent may dominate commercial development even if Patent 10,603,314 remains in force. Conversely, an expired compound patent would not eliminate liability under a live method-of-use patent.
What formulation patents are protected by US 10,603,314?
The claims provide only minimal formulation coverage. Claim 1 requires a pharmaceutical composition comprising a unit dosage, but it does not claim:
- a specific excipient;
- a particular dosage strength;
- a sustained-release system;
- a coating;
- a crystalline form;
- a particle-size distribution;
- a specific salt;
- a lipid or nanoparticle carrier; or
- a stability profile.
A conventional tablet or capsule can potentially satisfy the unit-dosage limitation. The patent should not be treated as a robust formulation patent. Formulation-specific freedom-to-operate requires separate review of the relevant product’s composition, solid-state, and manufacturing patent families.
What manufacturing and IP barriers affect commercialization?
A company commercializing an irreversible EGFR inhibitor would face at least four separate IP questions:
- Whether the active compound is covered by an unexpired composition patent.
- Whether the selected formulation is covered by a separate product patent.
- Whether manufacturing intermediates or processes are protected.
- Whether the intended label or promotional use practices the method claims in Patent 10,603,314.
The fourth question is narrower than the first three. A company may avoid the method claims while still facing compound or formulation patents. Conversely, a company with freedom to make and sell a compound could still face method-of-use exposure if it intentionally markets daily treatment for gefitinib- or erlotinib-resistant NSCLC.
What patent litigation affects US 10,603,314?
The supplied claim text does not establish a reported infringement action, ANDA litigation, Paragraph IV notice, or settlement agreement involving US Patent 10,603,314. No litigation conclusion should be drawn solely from the patent claims.
For diligence purposes, the relevant litigation triggers would be:
- commercialization of EKB-569 or HKI-357;
- approval of another irreversible EGFR inhibitor with the claimed binding profile;
- an ANDA or 505(b)(2) application tied to an approved reference product;
- labeling that expressly identifies gefitinib- or erlotinib-resistant NSCLC; or
- evidence that a marketed product binds EGFR Cys773 or HER2 Cys805 covalently.
What generic entry risks exist?
Generic entry risk is low if no approved reference product corresponds to the claimed compounds. It becomes more significant if a later approved product practices the claim and the patent is listed in the Orange Book.
Possible launch scenarios include:
| Scenario |
Risk under Patent 10,603,314 |
| Generic launches for an unrelated indication |
Low, unless the marketed label or conduct reaches resistant NSCLC |
| Generic uses a reversible EGFR inhibitor |
Low under the supplied claims |
| Generic uses a covalent inhibitor binding a different residue |
Potentially lower, subject to proof of mechanism |
| Generic omits the resistant-NSCLC indication |
May support a section viii strategy if legally available |
| Generic uses daily oral dosing in resistant NSCLC |
Higher claim risk |
| Competitor develops a new compound with Cys773/Cys805 binding |
Potential method-of-use exposure |
| Compound is administered intermittently |
May avoid the daily limitation, depending on actual regimen |
Inducement risk can arise even where the manufacturer does not directly administer the drug. Labeling, promotional materials, clinical protocols, and product distribution can be relevant to whether a company encourages patented use under US patent law.[4]
What geographic coverage does the patent provide?
US Patent 10,603,314 provides territorial rights in the United States. It does not independently block treatment, manufacture, sale, or use outside the United States.
International protection would require corresponding patents in the relevant jurisdictions. The strongest commercial jurisdictions for review would include:
- European Patent Office member states;
- Japan;
- China;
- Canada;
- South Korea;
- Australia; and
- jurisdictions where the active ingredient or finished product will be manufactured.
A PCT publication would not itself create enforceable rights in every PCT country. National-phase patents and their individual expiration, lapse, opposition, and maintenance records control.
Key Takeaways
- US Patent 10,603,314 is a targeted method-of-use patent for resistant NSCLC.
- Claim 1 requires daily administration of a unit-dose irreversible EGFR-family inhibitor.
- The inhibitor must covalently bind EGFR Cys773 or HER2/erbB-2 Cys805.
- EKB-569 and HKI-357 are expressly covered by dependent claim 2.
- The patent does not broadly claim the chemical composition, formulation, synthesis, or manufacturing process of the inhibitors.
- Its commercial relevance depends on an approved product or marketed use that satisfies the resistance, dosing, disease, and residue limitations.
- EKB-569 and HKI-357 do not appear to provide an FDA-approved commercial reference product for ordinary ANDA litigation.
- Biosimilar risk is not applicable because the claimed agents are small molecules.
- Orange Book status cannot be inferred from issuance alone and is not established by the supplied claims.
- Generic or competitor risk is highest for a covalent inhibitor used daily in gefitinib- or erlotinib-resistant NSCLC.
FAQs
Does US Patent 10,603,314 cover osimertinib?
Not automatically. Osimertinib would fall within the patent only if its use satisfies every limitation of claim 1, including daily treatment of gefitinib- or erlotinib-resistant NSCLC and covalent binding to EGFR Cys773 or HER2 Cys805. Separate osimertinib composition, formulation, and method patents may control the product.
Can a company avoid this patent by changing the EGFR binding residue?
Potentially. A covalent inhibitor that does not bind EGFR Cys773 or HER2 Cys805 may avoid literal infringement of the supplied claims. The final assessment would depend on the evidence and any doctrine-of-equivalents theory.
Does a combination with radiation create a separate patent barrier?
Claim 6 creates a narrower combination-use position. It applies only when the base treatment in claim 1 is also performed and radiation is administered. Radiation alone does not practice claim 6.
Is a once-weekly irreversible EGFR inhibitor covered?
A once-weekly regimen may avoid the express daily-administration limitation. The legal result would depend on the actual dosing instructions, treatment protocol, and claim construction.
Can a generic omit the patented indication from its label?
A label carve-out may reduce induced-infringement risk where the omitted indication is the only patented use. Its availability depends on the reference product, FDA-approved uses, Orange Book listing, and whether the remaining labeling still encourages the patented treatment.
References
- United States Patent and Trademark Office. (2020). U.S. Patent No. 10,603,314, methods of treating gefitinib and/or erlotinib-resistant non-small cell lung cancer.
- 35 U.S.C. §§ 154, 156 (2023).
- U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations (Orange Book).
- 35 U.S.C. §§ 271(b), 271(e) (2023).
