US Patent 8,841,330: Sorafenib Patent Scope, Claims, Expiration, Orange Book Status, and Generic Risk

US Patent 8,841,330 covers methods of treating specified tumors with sorafenib, including sorafenib tosylate, the active pharmaceutical ingredient in Bayer’s Nexavar. The patent is a method-of-use patent, not a composition-of-matter patent. Its principal commercial relevance is hepatocellular carcinoma because the claims expressly cover liver tumors and the FDA-approved Nexavar label includes unresectable hepatocellular carcinoma. The claims do not cover every sorafenib use, dosage regimen, formulation, or manufacturing process.

What drug does US Patent 8,841,330 protect?

The claimed compound is sorafenib, chemically identified as:

N-(4-chloro-3-(trifluoromethyl)phenyl)-N′-(4-(2-(N-methylcarbamoyl)-4-pyridyloxy)phenyl)urea.

The claimed salt in claims 7 through 12 and claim 14 is sorafenib tosylate, also called sorafenib p-toluenesulfonate. Nexavar tablets contain sorafenib tosylate, equivalent to 200 mg of sorafenib per tablet.[1]

Item	Information
Active ingredient	Sorafenib
Commercial salt	Sorafenib tosylate
Brand	Nexavar
Original innovator	Bayer and Onyx Pharmaceuticals
FDA application	NDA 021923
Dosage form	Oral tablets
FDA-approved indications	Unresectable hepatocellular carcinoma, advanced renal cell carcinoma, and radioactive iodine-refractory differentiated thyroid cancer
Patent type	Method of treatment
Patent	US 8,841,330 B2
Issue date	September 23, 2014
Claimed tumor types	Prostate, breast, liver, ovary, and cervix

The patent claims the active molecule and its pharmaceutically acceptable salts in treatment methods. It does not claim sorafenib as a new chemical entity in the abstract.

What are the claims of US Patent 8,841,330?

Claims 1 through 6 cover treatment with sorafenib or a pharmaceutically acceptable salt. Claims 7 through 12 separately cover treatment with sorafenib tosylate. Claims 13 and 14 focus specifically on liver cancer.

Claim structure

Claims	Subject matter	Tumor limitation
1	Sorafenib or pharmaceutically acceptable salt	Prostate, breast, liver, ovary, or cervix
2	Dependent method	Prostate
3	Dependent method	Breast
4	Dependent method	Liver
5	Dependent method	Ovary
6	Dependent method	Cervix
7	Sorafenib tosylate	Prostate, breast, liver, ovary, or cervix
8	Dependent method	Prostate
9	Dependent method	Breast
10	Dependent method	Liver
11	Dependent method	Ovary
12	Dependent method	Cervix
13	Sorafenib or salt	Liver cancer
14	Sorafenib tosylate	Liver cancer

The independent claims require four core elements:

A human or animal patient.
A tumor within one of the specified anatomical categories.
Administration of an effective amount.
Use of sorafenib, a pharmaceutically acceptable salt, or specifically sorafenib tosylate.

How broad is the scope of claim 1?

Claim 1 is broad in chemical and therapeutic terms but narrow in disease classification.

Chemical scope

Claim 1 covers:

The specifically identified sorafenib molecule.
Pharmaceutically acceptable salts of sorafenib.
Administration in an effective amount.

The claim does not require sorafenib tosylate specifically. A different pharmaceutically acceptable salt could fall within claim 1 if it is legally established to be a salt of the claimed sorafenib compound.

Claim 7 is narrower because it requires the tosylate salt. A product containing sorafenib tosylate would be the clearest chemical match for claim 7.

Disease scope

The claim is limited to tumors of the:

Prostate
Breast
Liver
Ovary
Cervix

The language does not expressly cover renal cell carcinoma, thyroid cancer, pancreatic cancer, colorectal cancer, lung cancer, or other tumors outside those categories.

The liver limitation is the most commercially important because it overlaps with Nexavar’s FDA-approved hepatocellular carcinoma indication.[1]

Administration scope

The claims do not specify:

Dose
Dose frequency
Treatment duration
Route of administration
Tablet strength
Combination therapy
Patient biomarker
Disease stage
Prior treatment
Tumor genotype
Radiographic response
Treatment line

An accused product or treatment does not avoid the claim merely because it uses a different dose or schedule, provided the method otherwise satisfies the claim limitations.

What is the difference between claims 1 and 7?

Claim 1 covers sorafenib and its pharmaceutically acceptable salts. Claim 7 specifically covers sorafenib tosylate.

This creates overlapping but distinct protection:

Sorafenib tosylate may fall within claim 1 as a pharmaceutically acceptable salt.
Sorafenib tosylate is expressly recited in claim 7.
A different pharmaceutically acceptable salt may fall within claim 1 but not claim 7.
The free base may fall within claim 1 but not claim 7.

The separate tosylate claims reduce dependence on the broader salt language and provide a direct claim to the commercial salt used in Nexavar.

What do claims 13 and 14 add for liver cancer?

Claims 13 and 14 create a separate liver-cancer claim set.

Claim 13 covers treatment of liver cancer with sorafenib or a pharmaceutically acceptable salt. Claim 14 narrows that method to sorafenib tosylate.

Compared with claim 4 and claim 10, claims 13 and 14 use “liver cancer” and “in need thereof” language rather than simply “a tumor of the liver.” That drafting distinction may matter in litigation over whether a particular hepatic tumor falls within the claim.

The liver-cancer claims are important because:

Nexavar has an FDA-approved indication for unresectable hepatocellular carcinoma.
A generic applicant seeking approval for the liver-cancer indication could create induced-infringement exposure if the patent remained enforceable.
A section viii labeling carve-out could be relevant if the listed patent covered only a patented indication and the generic product could lawfully omit that indication from its label.[2]

What does US Patent 8,841,330 not cover?

The patent does not, based on the quoted claims, expressly cover:

Sorafenib’s chemical composition without a treatment step.
Sorafenib manufacturing processes.
Sorafenib crystal forms.
Tablet excipients.
A particular dissolution profile.
A particular particle size.
A specific daily dose.
Combination therapy with bevacizumab, atezolizumab, chemotherapy, or hormonal therapy.
Renal cell carcinoma treatment.
Thyroid cancer treatment.
Sale of sorafenib tablets without evidence of induced or contributory infringement.

The patent therefore operates differently from a composition-of-matter patent. A method claim generally requires proof that the accused party practiced, induced, or contributed to the claimed treatment method. Under US law, a generic manufacturer can face inducement allegations based on its prescribing information, marketing, labeling, or other evidence of intent.[3]

What is the patent landscape for sorafenib and Nexavar?

Sorafenib has several layers of potential intellectual-property protection:

Protection layer	Typical subject matter	Relevance
Composition-of-matter patents	Sorafenib molecule and related diaryl urea compounds	Principal early protection
Salt patents	Sorafenib tosylate and related salts	Protect commercial API form
Method-of-use patents	Treatment of particular tumor types	Indication-specific barriers
Formulation patents	Tablets, excipients, release characteristics	Product-level protection
Manufacturing patents	Synthesis, purification, crystallization	API supply and process barriers
Regulatory exclusivity	NDA, orphan or pediatric exclusivity where applicable	Independent of patent validity

US Patent 8,841,330 is most accurately categorized as a tumor-treatment use patent. It should not be treated as the primary sorafenib composition patent.

Composition-of-matter protection

The earliest sorafenib patent families were directed to substituted diaryl urea compounds, including sorafenib. Those patents generally provide broader protection against making, using, or selling the active compound than a disease-specific use patent.

Their expiry dates are controlled by the earliest effective nonprovisional filing date, subject to patent-term adjustment, patent-term extension, terminal disclaimers, and other statutory calculations. The 2014 issue date of US 8,841,330 does not itself establish a 20-year term beginning in 2014.[4]

Salt and solid-form protection

Sorafenib tosylate protection may be relevant to:

Selection of the tosylate salt.
Pharmaceutical stability.
Crystallinity.
Solubility and handling.
Tablet manufacture.
API purification.

Claim 7 and claim 14 provide direct method claims involving the tosylate salt. They do not, on their face, claim every physical form or manufacturing method for sorafenib tosylate.

Formulation protection

Nexavar is an immediate-release oral tablet. A formulation patent would need to claim features such as composition, excipient ratios, dissolution performance, coating, particle size, or manufacturing conditions. The quoted claims of US 8,841,330 contain none of those limitations.

A formulation patent can create a separate infringement issue even after an active-ingredient or method patent expires. Conversely, expiration of a formulation patent does not eliminate a surviving method patent.

What is the Orange Book status of US Patent 8,841,330?

The FDA Orange Book is the controlling public source for patents submitted for listing against an approved small-molecule drug application.[5]

For Nexavar, a listed patent covering hepatocellular carcinoma would have direct relevance to an ANDA applicant seeking approval for that indication. The legal effect depends on:

Whether US 8,841,330 is listed against NDA 021923.
The expiration date recorded by FDA.
Whether the listing identifies a method-of-use claim.
Whether the applicant certifies to the patent under section 505(j)(2)(A)(vii).
Whether the applicant omits the patented indication under a section viii statement.

A patent listing does not establish validity or enforceability. FDA listing also does not determine whether a court would find infringement. The patent holder must enforce the patent in district court after receiving a Paragraph IV notice.

When does US Patent 8,841,330 lose exclusivity?

The patent’s enforceable term must be determined from the USPTO record using:

Earliest effective US filing date.
Patent-term adjustment.
Any patent-term extension.
Any terminal disclaimer.
Continuation or divisional relationship.
Corrected certificates or post-grant proceedings.

The patent’s September 23, 2014 issue date is not the expiration date. Because the patent appears to belong to an older sorafenib-related family, its term is likely governed by an earlier priority chain rather than by the 2014 issue date.

The practical commercial point is that US 8,841,330 should be analyzed together with the earlier sorafenib composition and salt patents. A generic launch may still be blocked by a separate surviving patent even if the use patent expires first.

Nexavar received FDA approval in December 2005. FDA approval triggered five years of new-chemical-entity exclusivity, subject to statutory exceptions, and any additional pediatric exclusivity would have been temporary. Regulatory exclusivity is separate from the patent term.[1][2]

Which companies challenged Nexavar patent protection?

Generic sorafenib development has involved ANDA applicants seeking approval after the principal Nexavar exclusivity period. Typical challenges can include:

Paragraph IV certification that a listed patent is invalid, unenforceable, or not infringed.
Paragraph III certification accepting delayed approval until patent expiry.
Section viii statements carving out patented methods from the labeling.
Declaratory or district-court litigation initiated after a Paragraph IV notice.

The relevant competitive field includes generic-drug companies rather than biosimilar developers. Sorafenib is a chemically synthesized small molecule, so abbreviated new drug applications, not biosimilar applications under the Biologics Price Competition and Innovation Act, are the relevant pathway.[6]

Publicly reported Nexavar litigation should be matched to the specific patent, ANDA number, product labeling, and settlement terms. A settlement allowing a generic launch on a defined date does not necessarily invalidate the patent or authorize all indications before that date.

What Paragraph IV risks arise from US Patent 8,841,330?

A Paragraph IV challenge could attack the patent on several grounds.

Invalidity risks

Potential arguments include:

Lack of written description for the full salt scope in claim 1.
Enablement of all claimed tumor types.
Obviousness based on earlier sorafenib disclosures and tumor-treatment data.
Indefiniteness involving “effective amount.”
Anticipation by earlier disclosures of sorafenib treatment in the claimed cancers.
Double-patenting or terminal-disclaimer issues within the patent family.

The single-compound nature of the claims can strengthen written-description arguments relative to a broad genus claim. The main vulnerability is more likely to concern the therapeutic application and the tumor categories than chemical identity.

Noninfringement risks

A generic applicant could argue that:

Its label omits the patented tumor indication.
The approved label does not instruct treatment of the claimed cancers.
The product is sold for a nonclaimed indication.
Sorafenib tosylate does not meet a claim limitation if the claim requires another chemical form.
The patent expired before commercial launch.

For claim 14, a product containing sorafenib tosylate would face a closer chemical fit than a product containing only the free base. For claim 13, the central dispute would be whether the labeling and induced-use evidence establish treatment of liver cancer.

How strong is the patent estate for sorafenib?

US Patent 8,841,330 has moderate claim strength as an indication patent and limited breadth outside the specified cancers.

Factor	Assessment
Chemical specificity	Strong; sorafenib is precisely identified
Tosylate coverage	Stronger in claims 7-12 and 14
Tumor coverage	Narrow; limited to five listed categories
Dosage protection	None stated
Formulation protection	None stated
Manufacturing protection	None stated
HCC commercial overlap	High
RCC overlap	Low or absent from the quoted claims
Thyroid-cancer overlap	Low or absent from the quoted claims
Biosimilar relevance	None; sorafenib is a small molecule
Generic carve-out potential	Material for non-liver indications
Dependence on labeling evidence	High

The estate is stronger when the accused generic label includes hepatocellular carcinoma and weaker when the label omits the claimed uses. The patent is also less useful against a competitor developing a distinct sorafenib formulation or a new chemical entity that does not contain sorafenib.

How does sorafenib compare with competing liver-cancer drugs?

Sorafenib competes in a treatment landscape that includes systemic therapies with different mechanisms and patent profiles.

Drug	Company or originator	Modality	Liver-cancer relevance	Patent-risk profile
Sorafenib	Bayer/Onyx	Small-molecule multikinase inhibitor	Approved for unresectable HCC	ANDA and method-patent risk
Lenvatinib	Eisai	Small-molecule multikinase inhibitor	Approved first-line alternative for unresectable HCC	Separate composition and method estate
Atezolizumab plus bevacizumab	Roche/Genentech	Biologic combination	Approved first-line HCC regimen	Biologic and combination-method issues
Durvalumab plus tremelimumab	AstraZeneca	Biologic combination	Approved first-line HCC regimen	Biologic patent and regulatory exclusivity issues
Regorafenib	Bayer	Small-molecule multikinase inhibitor	Used after sorafenib in HCC	Separate molecule and indication claims
Cabozantinib	Exelixis	Small-molecule multikinase inhibitor	Used in previously treated HCC	Separate composition and method estate

Sorafenib’s principal competitive disadvantage is clinical and commercial rather than purely patent-based: newer combination regimens and alternative kinase inhibitors have reduced reliance on Nexavar in some treatment lines. Its principal generic advantage is the availability of an ANDA pathway without biosimilar complexity.

What licensing deals affect the sorafenib patent landscape?

Bayer discovered and developed sorafenib with Onyx Pharmaceuticals. Onyx obtained commercialization rights in the United States and later became part of Amgen. Nexavar commercialization therefore reflects a collaboration and licensing structure rather than a single-originator ownership model.[7]

The commercial rights structure matters because:

Patent ownership and NDA sponsorship can be held by different entities.
Enforcement rights may depend on license agreements.
Revenue allocation can differ from patent ownership.
A settlement with one generic applicant may not bind another applicant.
Acquisitions can change the identity of the NDA holder or patent assignee without changing the patent claims.

A license or corporate acquisition does not extend the patent term.

What revenue exposure does US Patent 8,841,330 create?

The patent’s revenue exposure is concentrated in sorafenib sales for liver cancer. It does not independently protect the full Nexavar revenue base because the claims do not expressly cover renal cell carcinoma or differentiated thyroid cancer.

Revenue exposure depends on:

Share of Nexavar sales attributable to hepatocellular carcinoma.
Whether generic labeling includes or excludes liver cancer.
The enforceable expiration date.
Number and timing of ANDA launches.
Generic substitution and price erosion.
Surviving composition, salt, formulation, or process patents.
Any authorized generic or launch settlement.

A generic launch with a liver-cancer carve-out could erode RCC and thyroid-cancer sales while leaving the claimed HCC indication contested. A full-label launch would create materially greater induced-infringement exposure if the patent remained enforceable.

What geographic coverage does US Patent 8,841,330 provide?

US 8,841,330 provides protection only in the United States. Foreign counterparts require separate analysis in each jurisdiction.

Geographic risk should be reviewed across:

United States
European Patent Convention states
Japan
China
Canada
Australia
South Korea
Brazil
India

A US patent does not block manufacture, sale, or use outside the United States. Foreign patent terms, claim amendments, opposition outcomes, supplementary protection certificates, and national litigation can differ materially.

Key Takeaways

US 8,841,330 is a sorafenib method-of-treatment patent.
The claims cover prostate, breast, liver, ovarian, and cervical tumors.
Claims 7-12 and 14 specifically recite sorafenib tosylate.
Claims 13 and 14 create a focused liver-cancer protection layer.
The patent does not claim sorafenib’s composition, formulation, dosage, or manufacturing process in the quoted claims.
Its strongest commercial overlap is with Nexavar’s hepatocellular carcinoma indication.
It does not expressly cover renal cell carcinoma or differentiated thyroid cancer.
Sorafenib is a small molecule, so generic ANDA litigation, not biosimilar litigation, is the relevant pathway.
Patent expiration must be calculated from the family’s earliest effective filing date and applicable term adjustments, not from the 2014 issue date.
The overall generic-entry risk depends on this patent together with the earlier composition, salt, formulation, and process patents.

FAQs About US Patent 8,841,330 and Sorafenib

Does US Patent 8,841,330 cover Nexavar tablets?

It can cover treatment using Nexavar tablets when the tablets contain sorafenib tosylate and are administered for one of the claimed tumor types, particularly liver cancer. It does not claim the tablet formulation itself in the quoted claims.

Can a generic company launch sorafenib for renal cell carcinoma?

The quoted claims do not expressly cover renal cell carcinoma. A generic applicant would still need to assess other listed patents, FDA labeling requirements, and inducement theories before launching.

Is sorafenib tosylate protected separately from sorafenib?

The patent separately recites sorafenib tosylate in claims 7 through 12 and claim 14. Sorafenib tosylate may also fall within claim 1 as a pharmaceutically acceptable salt.

Does US Patent 8,841,330 cover sorafenib combinations?

No combination limitation appears in the quoted claims. The claims require administration of sorafenib or sorafenib tosylate but do not require or exclude combination treatment.

Are biosimilars a threat to Nexavar?

No. Sorafenib is a chemically synthesized small molecule. Competition proceeds through generic-drug ANDAs rather than biosimilar applications.

Can a generic omit liver cancer from its FDA label?

A section viii statement may allow an ANDA applicant to carve out a patented method from labeling where the statutory and FDA requirements are satisfied. The resulting label and promotional conduct must be assessed against potential induced-infringement claims.[2][3]

What is the main litigation vulnerability of US Patent 8,841,330?

The central issues are likely to be patent term, prior-art treatment disclosures, obviousness, the scope of “effective amount,” and whether the generic label induces treatment of the claimed tumor types.

References

U.S. Food and Drug Administration. (2023). Nexavar (sorafenib tosylate) prescribing information.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
35 U.S.C. § 271(e)(2), § 271(b), and § 271(c).
U.S. Patent and Trademark Office. (2024). Patent term adjustment and patent term extension guidance.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations.
Biologics Price Competition and Innovation Act, 42 U.S.C. § 262.
Amgen Inc. (2015). Annual report.
U.S. Patent No. 8,841,330 B2. (2014). Treatment of tumors. Go to source: U.S. Patent and Trademark Office.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	1140840	⤷ Start Trial	91280	Luxembourg	⤷ Start Trial
European Patent Office	1140840	⤷ Start Trial	PA2006008	Lithuania	⤷ Start Trial
European Patent Office	1140840	⤷ Start Trial	300242	Netherlands	⤷ Start Trial
European Patent Office	1140840	⤷ Start Trial	06C0034	France	⤷ Start Trial
European Patent Office	1140840	⤷ Start Trial	CA 2007 00002	Denmark	⤷ Start Trial
European Patent Office	1140840	⤷ Start Trial	SPC 031/2006	Ireland	⤷ Start Trial
European Patent Office	1140840	⤷ Start Trial	PA2006008,C1140840	Lithuania	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Summary for Patent: 8,841,330