United States Patent 10,568,859: Tazarotene Aerosol Foam Claims, Scope, Expiry and Competitive Patent Landscape

United States Patent No. 10,568,859 protects specific oil-in-water aerosol foam formulations containing tazarotene. Its commercial core is a nano- or submicron emulsion in which tazarotene is solubilized in an oil phase containing light mineral oil and diisopropyl adipate, stabilized principally with ceteareth-12, and delivered with a hydrocarbon propellant. The broadest independent composition claim is claim 1. Claim 8 is narrower but more closely aligned with a defined commercial formulation. Claim 9 covers topical treatment using the claim 8 composition.

The patent does not claim tazarotene generally, all tazarotene topical products, or every tazarotene foam. It claims a formulation architecture defined by ingredient classes, concentration ranges, surfactant identity, oil-phase particle size, and aerosol delivery.

What does United States Patent 10,568,859 protect?

The patent has three principal protection categories:

Oil-in-water aerosol foam compositions containing tazarotene.
A narrower formulation using light mineral oil, diisopropyl adipate, ceteareth-12 and specified concentration ranges.
A method of treating a skin disease, disorder or condition with the narrower composition.

Claim group	Subject matter	Commercial significance
Claims 1-7	Broad tazarotene oil-in-water aerosol foam composition	Broadest formulation protection
Claim 8	Defined light-mineral-oil and diisopropyl-adipate formulation	Likely closest to a reference commercial formulation
Claim 9	Treatment method using claim 8 composition	Supports method-of-use enforcement
Claim 10	Claim 8 composition with sorbic acid and a sorbate salt	Preservative-specific fallback
Claim 11	Claim 8 composition with approximately 100 nm mean oil-phase particle size	Nanoemulsion-specific limitation
Claims 12, 13 and 15	Ceteareth-12 and optional oleth-10 surfactant configurations	Surfactant-specific narrowing
Claim 14	Stability regardless of additional surfactant components	Functional stability limitation

What are the essential limitations of claim 1?

Claim 1 requires every one of the following elements:

An oil-in-water emulsion aerosol foam.
Tazarotene.
Water at approximately 65% to 90% by weight.
An oil at approximately 1% to 9% by weight.
An oil selected from a defined list or mixture of listed oils.
An oil-miscible organic solvent selected from:
- diisopropyl adipate;
- isopropyl myristate;
- octyl dodecanol;
- caprylic/capric triglycerides; or
- mixtures of those materials.
Ceteareth-12, oleth-10 or a mixture of those surfactants at approximately 1% to 8% by weight.
A hydrocarbon propellant.
Tazarotene solubilized in the oil phase.
Oil-phase particles smaller than approximately 1,000 nm.
Percentages calculated against total composition weight.

The claim is composition-based. A marketed product can infringe without copying the manufacturing process, brand, indication or label language if the finished composition satisfies the claim limitations.

How broad is the oil limitation?

The oil limitation is broader than the narrower commercial formulation. Claim 1 covers numerous oils, including:

mineral oil and light mineral oil;
paraffin and petrolatum;
isoparaffin;
isododecane;
isohexadecane;
squalane and squalene;
eicosane and isoeicosane;
tetradecene and didecene; and
certain specialty hydrocarbons.

A competitor using an oil outside the recited Markush group may avoid literal infringement of claim 1, subject to potential doctrine-of-equivalents issues. The listed oil must also be present in the claimed concentration range.

What does claim 8 add to the patent scope?

Claim 8 is materially narrower than claim 1. It requires:

Limitation	Claim 8 requirement
Water	Approximately 70% to 85%
Oil	Light mineral oil
Oil concentration	Approximately 3% to 8%
Organic solvent	Diisopropyl adipate
Organic-solvent concentration	Approximately 3% to 15%
Surfactant	Ceteareth-12
Surfactant concentration	Approximately 2% to 6%
Propellant	Hydrocarbon propellant
Physical structure	Oil-in-water aerosol foam
Drug distribution	Tazarotene solubilized in oil phase
Particle size	Less than approximately 1,000 nm

Claim 8 is vulnerable to design-around strategies that alter the oil, solvent, surfactant, concentration, propellant or emulsion structure. It is also more useful in product comparison because the required ingredients are specific and analytically testable.

Which claims are most commercially important?

Claims 1 and 8 carry the principal product risk.

Claim 1 creates the larger exclusionary zone because it covers multiple oil choices and broader concentration ranges. Claim 8 provides a more concrete formulation target and may be easier to prove through compositional testing.

Claims 11 and 12 are important fallback claims:

Claim 11 narrows the particle-size requirement to a mean of approximately 100 nm.
Claim 12 limits the surfactant component to ceteareth-12.

Claims 13 and 15 create additional surfactant-specific configurations. Their use of "consists of" generally creates a closed limitation for the defined surfactant component, although the overall product may contain other excipients that are not treated as part of that component.

Claim 10 may protect a formulation using sorbic acid together with a sorbate salt. This limitation is useful where the product’s preservative system is publicly disclosed or readily identified by analytical testing.

How does the particle-size limitation affect infringement?

The particle-size limitation is central to the patent’s technical distinction.

Claim 1 requires the oil phase to have a particle size below approximately 1,000 nm. Claim 11 narrows that requirement to a mean particle size of approximately 100 nm. A product can therefore fall within claim 1 while remaining outside claim 11 if its mean particle size is materially above 100 nm but below 1,000 nm.

The particle-size analysis raises several enforcement issues:

The claim does not specify a single measurement technique.
Dynamic light scattering, laser diffraction and microscopy can produce different results.
"Particle size" and "mean particle size" may refer to different statistical measures.
Product aging, temperature, dilution and sample preparation can change the measured distribution.
The relevant phase is the oil phase, not necessarily the foam bubble size.

A litigation-grade comparison would require testing of the finished product and a defined analytical protocol. Foam texture alone would not establish infringement.

What formulations are protected by the patent?

The strongest formulation target is a composition with the following profile:

Component	Claimed commercial-range profile
Active ingredient	Tazarotene
Continuous phase	Water
Water level	Approximately 70% to 85%
Oil phase	Light mineral oil
Light mineral oil	Approximately 3% to 8%
Oil-miscible solvent	Diisopropyl adipate
Solvent level	Approximately 3% to 15%
Surfactant	Ceteareth-12
Surfactant level	Approximately 2% to 6%
Delivery system	Aerosol foam
Propellant	Hydrocarbon
Dispersion	Oil-in-water
Drug location	Solubilized in oil phase
Particle size	Below approximately 1,000 nm

A product that uses tazarotene in a conventional cream, gel, lotion or non-aerosol emulsion is outside the literal scope of the composition claims unless it also satisfies the claimed aerosol-foam and formulation limitations.

What is the scope of the method-of-use claim?

Claim 9 covers treating a skin disease, disorder or condition by administering an effective amount of the claim 8 composition to the skin.

The claim does not identify a particular disease. Its breadth is therefore driven by the composition limitations rather than by a narrow indication. The claim requires use of the claim 8 formulation, not merely use of tazarotene for dermatological treatment.

Potential method-claim exposure depends on:

the composition actually supplied or used;
the product label and prescribing information;
physician and patient instructions;
the disease or condition treated; and
whether the formulation satisfies every claim 8 limitation.

A generic product with a different formulation could avoid claim 9 even if it carries a similar topical dermatology indication.

When does U.S. Patent 10,568,859 lose exclusivity?

The patent’s expiration date cannot be determined from the claims alone. U.S. patent term normally runs 20 years from the earliest effective nonprovisional filing date, subject to patent-term adjustment, patent-term extension, terminal disclaimers and other statutory calculations. The controlling dates appear in the USPTO patent record and the patent’s continuity statement.[1]

The relevant exclusivity analysis is:

Exclusivity category	Effect on this patent
Patent term	Controls the ordinary exclusion period
Patent-term adjustment	Can extend the ordinary term for USPTO delay
Patent-term extension	May apply only if statutory requirements are met
Terminal disclaimer	Can shorten the enforceable term if tied to another patent
Regulatory exclusivity	Separate from patent rights
Orange Book listing	Relevant only if the patent is listed for an approved drug product

FDA approval does not itself determine the patent expiration date. The Orange Book can identify listed patents and regulatory exclusivity for an approved product, but it does not replace the USPTO term calculation.[2]

What is the Orange Book status of the tazarotene aerosol foam patents?

Orange Book status must be assessed against the relevant approved drug product and NDA, not against the patent number alone. A patent may be technically relevant to a tazarotene formulation without being listed for a particular NDA.

The relevant regulatory distinctions are:

A formulation patent may be listed if it claims the approved drug product or an approved method of use.
A process patent generally has different listing relevance.
A patent not listed in the Orange Book can still support a separate infringement action.
FDA listing does not establish validity or infringement.
A Paragraph IV certification is directed to listed patents for the reference listed drug.

For tazarotene foam, the commercially relevant reference product is Fabior, a tazarotene topical foam approved by FDA for acne vulgaris in patients aged 12 years and older.[3] The patent claims supplied here should be compared with the approved Fabior formulation and the current Orange Book entries for its NDA. The patent number alone does not establish that Patent 10,568,859 is listed for Fabior.

What Paragraph IV challenges could target this patent?

A generic applicant could challenge the patent through an Abbreviated New Drug Application certification if the patent is listed for the relevant reference product. The principal theories would include:

Non-infringement

The applicant could design around one or more required limitations, such as:

using a non-hydrocarbon propellant;
using a nonlisted oil;
replacing diisopropyl adipate;
using a different surfactant;
using a particle size at or above the claimed threshold;
placing tazarotene outside the oil phase;
supplying a non-aerosol dosage form; or
operating outside the claimed concentration ranges.

Invalidity

Potential validity attacks would focus on:

anticipation by an earlier tazarotene emulsion or foam;
obviousness based on combining known tazarotene formulations with known aerosol-foam excipients;
indefiniteness of "about," "solubilized," "particle size" or "regardless";
lack of written description for the full oil and surfactant genera;
enablement across the full claimed composition space; and
lack of support for the functional stability language in claim 14.

The prior-art burden is likely highest for the combination of tazarotene, submicron oil-phase particles, the specified excipient classes and aerosol foam delivery. A reference disclosing tazarotene cream or gel alone would not necessarily anticipate these claims.

How strong is the patent estate?

The individual patent has moderate formulation breadth and a narrower commercial center.

Strength factor	Assessment
Active ingredient	Tazarotene is known, so the active itself contributes limited novelty
Dosage form	Aerosol foam narrows the field
Emulsion architecture	Oil-in-water structure adds a meaningful limitation
Particle size	Submicron oil-phase requirement may provide technical distinction
Excipients	Specific combinations strengthen product correlation but aid design-around
Concentration ranges	Create measurable boundaries and possible invalidity overlap issues
Method claim	Useful if the product composition is covered
Formulation detectability	Generally high through label, CMC disclosures and laboratory testing
Design-around potential	Moderate to high
Manufacturing barrier	Moderate; formulation know-how may remain important even where patent claims are avoided

The strongest practical protection arises when the marketed product matches claim 8, claims 11-12 and the related surfactant claims. The broadest legal protection arises from claim 1, but its many technical limitations create several possible design-around routes.

What manufacturing and intellectual-property barriers remain after patent expiry?

Patent expiry would remove the patent-based exclusion right, but a competing manufacturer could still face:

formulation-development costs;
aerosol valve and canister compatibility work;
emulsion stability requirements;
particle-size control;
preservative and microbial-limit validation;
scale-up risk;
device and packaging qualification;
FDA product-quality requirements; and
separate patents in continuation or related families.

The principal manufacturing know-how is likely concentrated in maintaining tazarotene solubilization, emulsion stability, foam performance and particle-size distribution through filling and shelf life. Those factors can delay entry even when a patent claim is no longer enforceable.

Does the patent cover Arazlo or ordinary tazarotene products?

On the supplied claims, no automatic coverage follows for Arazlo, tazarotene lotion, tazarotene gel, tazarotene cream or other non-aerosol products.

The claimed technology is tied to aerosol foam delivery and a specific oil-in-water formulation. A product using tazarotene in a lotion or gel would need to satisfy the aerosol-foam, propellant and emulsion limitations to fall within the literal composition claims. Product-by-product analysis would still require comparison with any continuation patents, formulation patents and Orange Book-listed rights associated with the relevant product.

What patent litigation and settlement risks affect generic entry?

A Paragraph IV notice involving a listed patent could lead to:

a 45-day period for the patent holder to file suit;
a 30-month FDA approval stay in the circumstances specified by the Hatch-Waxman Act;
claim-construction disputes over particle size and solubilization;
laboratory discovery concerning finished-product composition;
invalidity attacks based on earlier aerosol foams and topical retinoid formulations; and
settlement terms controlling the generic launch date.

A settlement may permit an authorized generic, a licensed generic, a delayed launch or entry before patent expiry under agreed conditions. No settlement terms should be inferred from the existence of Patent 10,568,859 alone. Litigation and settlement conclusions require the relevant docket and agreement.

How does this patent compare with conventional tazarotene patent protection?

Technology	Typical claim focus	Relationship to Patent 10,568,859
Tazarotene molecule	Active compound	Earlier foundational protection; generally expired or near expiry depending on claim
Tazarotene gel or cream	Vehicle, concentration, treatment use	Different formulation architecture
Tazarotene aerosol foam	Foam vehicle, propellant, emulsion and particle size	Directly relevant
Tazarotene lotion	Oil/water lotion without aerosol	Usually outside the supplied claims
Manufacturing process	Mixing, homogenization, filling or particle-size control	May create separate process exposure
Method of treatment	Treating acne or other dermatological conditions	Claim 9 covers use of the specified composition

Key Takeaways

Patent 10,568,859 is a formulation patent, not a broad tazarotene compound patent.
Claim 1 is the principal broad composition claim.
Claim 8 is the most commercially specific claim and requires light mineral oil, diisopropyl adipate and ceteareth-12 within defined ranges.
Claims 11-12 strengthen protection for approximately 100 nm particles and ceteareth-12-only formulations.
The patent does not automatically cover tazarotene gels, creams, lotions or non-aerosol products.
Particle-size measurement, oil-phase solubilization and the identity of the surfactant component are likely infringement battlegrounds.
The patent’s expiration date requires the USPTO continuity, filing, adjustment and disclaimer records.
Orange Book listing, Paragraph IV risk, litigation and settlement exposure must be evaluated against the relevant tazarotene reference product and NDA.
The estate provides meaningful protection for a formulation matching the claim 8 profile but leaves moderate design-around opportunities.

FAQs

Can a tazarotene foam avoid Patent 10,568,859 by using a different oil?

Potentially. A formulation using an oil outside claim 1’s recited oil group may avoid literal infringement, provided it also avoids equivalent treatment under the doctrine of equivalents and does not fall within another patent family.

Does a particle size above 1,000 nm avoid the patent?

It would generally avoid the express particle-size limitation in claims 1 and 8, but the measurement method and applicable "about" range matter. A product with a materially larger oil-phase particle size would have a stronger non-infringement position than a product near the claimed boundary.

Is diisopropyl adipate required in every claim?

No. Claims 1-7 permit several oil-miscible organic solvents. Claim 8 specifically requires diisopropyl adipate. A product using another listed solvent may still implicate claim 1 while avoiding claim 8.

Does claim 9 cover every use of tazarotene for acne?

No. Claim 9 requires use of the composition defined by claim 8. Tazarotene acne treatment using a gel, lotion or cream does not satisfy claim 9 merely because the active ingredient and indication are the same.

Can a generic launch before patent expiry?

A generic applicant may pursue a Paragraph IV challenge, a non-infringing formulation, a successful invalidity defense, a license, an authorized-generic arrangement or a settlement-based launch. The commercial launch date depends on the listed-patent record, litigation outcome and any enforceable agreement.

References

United States Patent and Trademark Office. (n.d.). Patent term adjustment and patent term calculation resources. https://www.uspto.gov/patents/laws/adjustment
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, commonly known as the Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases
U.S. Food and Drug Administration. (2012). Fabior: Prescribing information. NDA 203-669. https://www.accessdata.fda.gov/drugsatfda/dao/index.cfm

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Mayne Pharma	FABIOR	tazarotene	AEROSOL, FOAM;TOPICAL	202428-001	May 11, 2012		RX	Yes	Yes	10,568,859	⤷ Start Trial	Y			TOPICAL TREATMENT OF ACNE VULGARIS IN PATIENTS 12 YEARS OF AGE OR OLDER	⤷ 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	2010217190	⤷ Start Trial
Brazil	PI1008037	⤷ Start Trial
Canada	2753497	⤷ Start Trial
Chile	2011002053	⤷ Start Trial
China	102438590	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 10,568,859

Which drugs does patent 10,568,859 protect, and when does it expire?

Summary for Patent: 10,568,859