US Patent 11,679,115: Claim Scope, Exclusivity, Orange Book Position, and Generic Risk

US Patent 11,679,115 protects a narrow topical combination of halobetasol propionate and tazarotene in a specified lotion vehicle. Its strongest protection is directed to the commercial Duobrii-type formulation: halobetasol propionate 0.01%, tazarotene 0.045%, diethyl sebacate, light mineral oil, two specified carbomers, sorbitan monooleate, sorbitol, parabens, edetate disodium, sodium hydroxide, and a pH of 5.5 ± 0.5. The patent also covers psoriasis-treatment use of the broader claim 1 composition.

The patent is commercially important because it combines active-ingredient, excipient, concentration, physical-vehicle, and method-of-use limitations. A competing product must avoid the complete claim combination, invalidate the patent, or obtain a license. The principal exposure is from an ANDA product that duplicates the claimed strengths and vehicle rather than from a biosimilar.

What drug does US Patent 11,679,115 protect?

US Patent 11,679,115 protects a topical pharmaceutical composition containing:

Component	Claimed concentration or requirement
Halobetasol propionate	About 0.01% by weight
Tazarotene	About 0.045% by weight
Diethyl sebacate	About 2.5% to 3.5%
Mineral oil	About 7.5% to 8.5%
Carbomer copolymer type B	About 0.3% to 0.5%
Carbomer homopolymer type A	About 0.5% to 0.7%
Purified water	Required carrier component
Sorbitan monooleate	About 0.05% to 0.2% in dependent claims
Sorbitol solution, 70%	About 10% to 11%
Methyl paraben	About 0.1% to 0.2%
Propyl paraben	About 0.02% to 0.04%
Edetate disodium dihydrate	About 0.03% to 0.06%
Sodium hydroxide	Amount sufficient to produce pH 5.5 ± 0.5

The claimed active ingredients correspond to the approved topical psoriasis product Duobrii lotion, which contains halobetasol propionate 0.01% and tazarotene 0.045%.[2]

Claim 1 is the principal composition claim. Claims 2 through 14 add excipients and narrower concentration ranges. Claims 15 through 17 cover treatment of psoriasis by topical application.

How broad is claim 1 of US Patent 11,679,115?

Claim 1 is narrow in ingredient identity but relatively broad in formulation implementation.

It requires all of the following:

Halobetasol propionate at approximately 0.01%.
Tazarotene at approximately 0.045%.
Diethyl sebacate at approximately 2.5% to 3.5%.
Mineral oil at approximately 7.5% to 8.5%.
Carbomer copolymer type B at approximately 0.3% to 0.5%.
Carbomer homopolymer type A at approximately 0.5% to 0.7%.
Purified water.
A topical pharmaceutical composition for treating psoriasis.

The claim uses “comprising,” making it an open-ended claim. A composition may contain additional excipients and remain within claim 1 if it contains every recited component at the claimed concentrations. The presence of additional ingredients does not ordinarily avoid infringement.

The claim does not require the exact commercial formulation. A product with additional preservatives, humectants, chelators, surfactants, or pH adjusters may still infringe claim 1.

The claim also does not expressly require:

A lotion dosage form by name;
Once-daily administration;
An eight-week treatment period;
A particular package or container;
A specific manufacturing process;
A specific particle size;
A particular emulsion type;
A particular viscosity;
A specific indication other than the claim’s psoriasis-use context.

Those limitations appear only in narrower dependent claims or the method claims.

What formulations are protected by claims 2 through 14?

Claims 2 through 14 progressively narrow the composition by adding conventional excipients and precise formulation parameters.

Claims 2 through 7

Claim 2 requires one or more components selected from:

A surfactant;
A humectant;
One or more antimicrobial preservatives;
A chelating agent;
A pH-adjusting agent.

Claims 3 through 7 identify specific versions of those excipients:

Sorbitan monooleate;
Sorbitol solution at 70%;
Methyl paraben and propyl paraben;
Edetate disodium dihydrate;
Sodium hydroxide producing a pH of 5.5 ± 0.5.

Claim 2 is materially broader than claims 3 through 7 because it does not require a particular identity or concentration for every added component. Claims 3 through 7 are more valuable against a product that uses the same commercial formulation.

Claims 8 through 13

Claim 8 requires all five categories of additional excipients:

A surfactant;
A humectant;
One or more antimicrobial preservatives;
A chelating agent;
A pH-adjusting agent.

Claims 9 through 13 then specify the same excipients and ranges identified in claims 3 through 7.

This claim group is narrower than claim 2 but creates a stronger product-specific position. A generic formulation containing the same excipient system would face a more direct infringement case under claims 8 through 13.

Claim 14

Claim 14 is the most commercially specific composition claim. It recites the following approximate formula:

Ingredient	Claim 14 concentration
Halobetasol propionate	About 0.01%
Tazarotene	About 0.045%
Diethyl sebacate	About 2.97%
Light mineral oil	About 8.03%
Carbomer copolymer type B	About 0.4%
Carbomer homopolymer type A	About 0.6%
Sorbitan monooleate	About 0.1%
Sorbitol solution, 70%	About 10.7%
Methyl paraben	About 0.17%
Propyl paraben	About 0.03%
Edetate disodium dihydrate	About 0.05%
Sodium hydroxide	pH 5.5 ± 0.5

Claim 14 has high product-identification value. It appears designed to cover a particular optimized commercial formulation rather than the full universe of halobetasol-tazarotene compositions.

Its limitation is that each additional ingredient and concentration must be proven. A generic applicant could attempt to avoid claim 14 by using a different mineral oil grade, a different carbomer, a different preservative system, or materially different concentrations. That design-around may still encounter claim 1 or another patent in the same family.

What method-of-use protection does US Patent 11,679,115 provide?

Claims 15 through 17 cover topical treatment of psoriasis.

Claim 15 requires:

Topical application;
To an affected body area;
In a subject suffering from psoriasis;
Of a composition according to claim 1;
One or more times per day;
For a sufficient treatment period.

Claim 16 narrows the method to once-daily application for eight weeks. Claim 17 combines the method with the precise claim 14 formulation.

The method claims create potential exposure where a generic product’s approved labeling instructs patients to use the same composition for psoriasis. An ANDA applicant may challenge method claims through a Paragraph IV certification, attempt a section viii carve-out where legally available, or alter labeling. A carve-out is difficult if the patented use corresponds to the principal approved indication and cannot be cleanly removed from the proposed label.[3]

How do the claims operate together?

The claims have a standard narrowing structure:

Claim group	Commercial scope	Relative breadth
Claim 1	Core active ingredients and vehicle	Broadest composition claim
Claims 2-7	Core formulation plus one or more excipient categories	Intermediate
Claims 8-13	Core formulation plus all specified excipient categories	Narrower
Claim 14	Exact commercial-style formulation	Narrowest composition claim
Claim 15	Psoriasis treatment using claim 1	Broad method claim
Claim 16	Once daily for eight weeks	Narrower method claim
Claim 17	Treatment using the claim 14-type formula	Narrowest method claim

The open-ended transition “comprising” expands the claims to formulations containing additional ingredients. The principal limiting terms are the identities and concentrations of the active ingredients, vehicle components, carbomers, and excipients.

When does US Patent 11,679,115 lose exclusivity?

The patent number and claim text alone do not establish the legally operative expiration date. Patent expiration depends on the earliest effective nonprovisional filing date, patent term adjustment, patent term extension, terminal disclaimers, and any applicable patent-term calculations under 35 U.S.C. § 154.[1]

The relevant timing should be evaluated in three separate categories:

Exclusivity category	Relevance
Patent term	Controls enforceable patent rights, subject to statutory adjustments
FDA regulatory exclusivity	Controls certain FDA approval restrictions and is separate from patent term
Orange Book listing	Provides notice and affects ANDA certification obligations

Duobrii received FDA approval in 2018 under NDA 210066.[2] FDA approval does not itself establish that every patent covering the product is listed in the Orange Book, nor does an Orange Book listing prove validity or enforceability.

A reliable expiration analysis must use the USPTO front-page data, continuity records, terminal-disclaimer records, and any patent-term adjustment or extension information. The issued patent’s publication number is not a substitute for that analysis.

What is the Orange Book status of US Patent 11,679,115?

Orange Book status cannot be determined from the supplied claims alone. Orange Book listing is a regulatory submission made by the NDA holder and is separate from patent issuance. The FDA Orange Book identifies patents submitted for approved drug products, including drug substance, drug product, and method-of-use patents where applicable.[4]

For a listed patent, an ANDA applicant generally must make one of the statutory patent certifications:

Paragraph I: no patent information has been submitted;
Paragraph II: the patent has expired;
Paragraph III: the applicant will wait until patent expiration;
Paragraph IV: the patent is invalid, unenforceable, or will not be infringed.

An accurate Orange Book assessment for Patent 11,679,115 requires the current FDA patent-listing record for NDA 210066. The claim text does not establish whether the patent is listed, the date of listing, or whether the NDA holder has removed or amended the listing.

Which companies are challenging US Patent 11,679,115?

The supplied patent and claim set do not identify an ANDA filer, Paragraph IV notice, district-court complaint, settlement, or inter partes review involving Patent 11,679,115.

A patent-specific challenge assessment should distinguish among:

A Paragraph IV certification submitted to FDA;
A notice letter sent to the NDA and patent holders;
A Hatch-Waxman infringement action;
A declaratory judgment action;
An inter partes review petition;
A settlement or license agreement.

A generic company may challenge the patent without immediately appearing in public litigation if the NDA holder does not sue within the statutory period or if the dispute is resolved commercially. Conversely, the absence of a known lawsuit would not establish the absence of a Paragraph IV certification.

What generic entry risks exist for Duobrii?

Generic entry risk is concentrated in three product configurations.

Exact-copy generic

An ANDA product that matches the active concentrations and the principal vehicle would face the highest infringement risk. Claims 1 and 14 would be the central composition claims. Claims 8 through 13 could provide overlapping protection if the generic uses the same excipient architecture.

Formulation design-around

A generic applicant could attempt to avoid infringement by changing:

Diethyl sebacate concentration;
Mineral oil identity or concentration;
Carbomer type;
Carbomer concentration;
Preservative system;
Humectant;
Surfactant;
pH;
Dosage form or vehicle.

The most defensible design-around would alter a claim 1 limitation, not merely an excipient that appears only in a dependent claim. A formulation that removes sorbitan monooleate may avoid claims 3, 9, and 14 but could still infringe claim 1.

Therapeutic-label design-around

A generic applicant could seek to remove or narrow psoriasis instructions. This strategy is constrained if psoriasis is the approved use for the reference product or if the formulation’s labeling necessarily directs treatment of psoriasis. Claims 15 through 17 therefore add litigation risk even where a product-formulation dispute remains contested.

How strong is the patent estate for halobetasol-tazarotene lotion?

Patent 11,679,115 has moderate-to-strong claim layering at the product level but limited breadth outside the claimed formulation.

Strengths

It covers both active ingredients at the commercial strengths.
It recites a defined vehicle with two carbomer systems.
It uses open-ended “comprising” language.
It includes multiple dependent formulation claims.
It includes psoriasis method claims.
Claim 14 targets a highly specific commercial composition.

Vulnerabilities

The claim requires numerous known excipients and concentration ranges.
The active ingredients were individually known before the claimed combination.
Obviousness may focus on combining halobetasol propionate and tazarotene for psoriasis and selecting a topical vehicle.
Anticipation or obviousness arguments may rely on earlier formulation disclosures, development records, or prior patents.
The term “about” can create disputes over the numerical boundaries.
Claims 14 and 17 may be vulnerable if the exact formula was disclosed in an earlier patent, regulatory filing, clinical document, or public product information.
The claims do not broadly cover every halobetasol-tazarotene dosage form.

The patent’s commercial strength depends on whether earlier prior art disclosed the same active combination and whether the specification demonstrates unexpected stability, efficacy, tolerability, or formulation performance. Claim text alone cannot resolve those validity questions.

How does Patent 11,679,115 compare with ingredient-level protection?

Protection type	Halobetasol propionate	Tazarotene	Combination formulation
Ingredient patents	Historically relevant but generally older	Historically relevant but generally older	Not applicable
Generic availability	Generic topical halobetasol products exist	Generic tazarotene products exist	Combination product is the main barrier
Main infringement issue	Active ingredient and dosage form	Active ingredient and dosage form	Exact combination, vehicle, and use
Biosimilar relevance	None	None	None
Primary FDA pathway	ANDA for equivalent small-molecule product	ANDA	ANDA referencing Duobrii

The commercial moat is therefore formulation and combination protection, not biologic exclusivity. Biosimilar litigation is not relevant because halobetasol propionate and tazarotene are small-molecule active ingredients.

What licensing and settlement issues affect the patent?

The patent record and claims supplied do not establish a license, covenant not to sue, Paragraph IV settlement, authorized-generic arrangement, or reverse-payment agreement.

Potential transaction structures include:

A license to the formulation patent family;
An authorized generic agreement;
A delayed-entry settlement;
A supply agreement for the reference product;
A patent challenge resolved without commercial launch;
A cross-license involving dermatology products.

Any settlement could materially alter the practical loss-of-exclusivity date without changing the nominal patent expiration date. FDA settlement reporting under applicable antitrust requirements and court filings are the principal public sources for confirming such arrangements.[5]

What manufacturing and geographic barriers exist?

The patent does not claim a manufacturing process. Its direct manufacturing value comes from the composition limitations, not process exclusivity.

A manufacturer could face technical barriers in reproducing:

The dual-carbomer rheology system;
Uniform distribution of two active ingredients;
Stability of tazarotene in the vehicle;
Preservative performance;
pH control;
Emulsion or suspension consistency;
Scale-up of the specified excipient concentrations.

Those technical barriers may increase development cost but do not independently create patent infringement. A process using a different vehicle or different mixing sequence could avoid this patent while remaining subject to separate process, formulation, or trade-secret rights.

US Patent 11,679,115 is enforceable in the United States. Foreign protection requires separate counterpart patents and national-stage or regional records. The US patent does not establish protection in Europe, Canada, Japan, or other markets.

What revenue exposure is associated with the patent?

The patent is relevant to the revenue base of the halobetasol-tazarotene combination product marketed as Duobrii. The financial exposure depends on:

Net sales of the reference product;
The number and timing of ANDA filers;
Whether a first Paragraph IV filer receives 180-day exclusivity;
The number of overlapping formulation patents;
The availability of an authorized generic;
The commercial discount required for generic substitution;
The degree of psoriasis-label overlap.

No revenue figure can be derived from the patent claims. Patent risk should be modeled against product net sales, not total dermatology revenue or total company revenue.

Key Takeaways

US Patent 11,679,115 claims a halobetasol propionate 0.01% and tazarotene 0.045% topical composition.
Its principal vehicle limitations are diethyl sebacate, mineral oil, carbomer copolymer type B, carbomer homopolymer type A, and purified water.
Claim 14 is the most commercially specific claim and closely tracks a Duobrii-type formulation.
Claims 15 through 17 add psoriasis-treatment protection, including once-daily use for eight weeks.
The open-ended “comprising” language permits additional ingredients without necessarily avoiding claim 1.
The strongest generic design-around strategy would change a claim 1 limitation, not only a dependent-claim excipient.
Biosimilar risk is irrelevant because the product contains small-molecule drugs.
Patent expiration, Orange Book listing, Paragraph IV activity, litigation, and settlements cannot be established from the claim text or patent number alone.
The patent’s practical value lies in combination and formulation protection rather than broad ingredient-level exclusivity.

FAQs About US Patent 11,679,115

Does Patent 11,679,115 cover all halobetasol propionate and tazarotene products?

No. It requires specified concentrations and vehicle components. A product using different active strengths or a materially different carrier may fall outside claim 1.

Can a generic avoid the patent by removing the preservatives?

Removing methyl paraben and propyl paraben may avoid some dependent claims, but it would not necessarily avoid claim 1, which does not require those preservatives.

Does once-daily use infringe claim 16?

Potentially, if the product uses the claim 1 composition and the labeling or actual use instructs once-daily treatment for eight weeks. The full claim limitations must be met.

Is a tazarotene foam or cream covered by this patent?

Not automatically. The product would still need to contain every limitation of the asserted claim, including the specified carrier components and concentration ranges.

Does FDA approval confirm that Patent 11,679,115 is valid?

No. FDA approval and patent validity are separate legal and regulatory determinations. FDA approval does not adjudicate novelty, obviousness, written description, enablement, or enforceability.

References

United States Patent and Trademark Office. (2023). US Patent No. 11,679,115. https://patents.google.com/patent/US11679115
U.S. Food and Drug Administration. (2018). Duobrii prescribing information. https://www.accessdata.fda.gov
U.S. Food and Drug Administration. (2020). Approved drug products with therapeutic equivalence evaluations. https://www.fda.gov/drugs/drug-approvals-and-databases/orange-book
U.S. Food and Drug Administration. (2023). Hatch-Waxman amendments and abbreviated new drug applications. https://www.fda.gov/drugs
Federal Trade Commission. (2023). Agreements filed with the Federal Trade Commission under the Medicare Prescription Drug, Improvement, and Modernization Act. https://www.ftc.gov/legal-library/browse/federal-register-notices/filing-agreements-filed-under-medicare-prescription-drug-improvement-modernization-act-2003

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Bausch	DUOBRII	halobetasol propionate; tazarotene	LOTION;TOPICAL	209354-001	Apr 25, 2019	AB	RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial	Y			TOPICAL TREATMENT OF PLAQUE PSORIASIS IN ADULTS	⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Patented / Exclusive Use	>Submissiondate

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2016279801	⤷ Start Trial
Brazil	112017027332	⤷ Start Trial
Brazil	112019023817	⤷ Start Trial
Canada	2988577	⤷ Start Trial
Canada	3063371	⤷ Start Trial
China	108282998	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 11,679,115

Which drugs does patent 11,679,115 protect, and when does it expire?

Summary for Patent: 11,679,115