US Patent 10,828,369: Efinaconazole Nail-Solution Claims, Scope, Expiration Risk, and Patent Landscape

US Patent 10,828,369 protects a narrow but commercially important formulation of efinaconazole for topical treatment of nail and nail-bed disorders. The patent is directed to a low-surface-tension, non-film-forming solution containing efinaconazole, ethanol, cyclomethicone, diisopropyl adipate, and C12-15 alkyl lactate. The strongest coverage is concentrated in the formulation combination, especially a 10% efinaconazole solution with specified solvent and emollient ranges.

The patent does not broadly claim efinaconazole as a molecule, every efinaconazole nail treatment, or every topical formulation. Infringement requires satisfaction of all limitations of at least one asserted claim.

What drug and product does US Patent 10,828,369 cover?

The active ingredient identified in the claims is efinaconazole, chemically described as:

(2R,3R)-2-(2,4-difluorophenyl)-3-(4-methylenepiperidine-1-yl)-1-(1H-1,2,4-triazole-1-yl)butane-2-ol.

Efinaconazole is the active ingredient in Jublia, an FDA-approved 10% topical solution for onychomycosis caused by Trichophyton rubrum and Trichophyton mentagrophytes.[1]

The patent claims a formulation architecture rather than a new active pharmaceutical ingredient. Its central technical concept is a solution with:

Efinaconazole at 0.0001% to 30% w/w;
Ethanol at 10% to 80% w/w;
Cyclomethicone at 1% to 40% w/w;
Diisopropyl adipate plus C12-15 alkyl lactate at a combined 10% to 80% w/w;
Surface tension of 40 dynes/cm or less; and
No polymeric film-forming compound.

The claims are consistent with the product profile of an alcohol-based nail solution designed to wet and penetrate the nail without leaving a polymeric film.

What does claim 1 of US 10,828,369 require?

Claim 1 is the independent composition claim. A product must meet every limitation below to fall within its literal scope.

Claim limitation	Required condition
Active ingredient	Efinaconazole in the specified stereochemical form
Efinaconazole concentration	0.0001% to 30% w/w
Ethanol	10% to 80% w/w
Cyclomethicone	1% to 40% w/w
Diisopropyl adipate plus C12-15 alkyl lactate	Combined 10% to 80% w/w
Dosage form	Solution
Surface tension	40 dynes/cm or less
Film former	Composition does not comprise a polymeric film-forming compound
Indication	Topical treatment of a disorder of the nail or nail bed

The claim uses “comprising,” which generally makes it open-ended. A formulation may contain additional excipients and still fall within the claim, provided the listed ingredients and limitations are present.

The claim does not require a particular package, applicator, treatment duration, dose per nail, pH, viscosity, or manufacturing process. Those omissions reduce the claim’s reach over delivery-device and manufacturing variations but increase its applicability to different commercial presentations containing the claimed formulation.

How broad is the efinaconazole formulation coverage?

The numerical ranges are broad, but the combination of required limitations is restrictive.

The active-ingredient range of 0.0001% to 30% w/w covers concentrations far below and above the commercial 10% strength. Ethanol at 10% to 80% w/w and cyclomethicone at 1% to 40% w/w also create substantial formulation latitude.

The principal narrowing feature is the combined requirement for:

Both diisopropyl adipate and C12-15 alkyl lactate;
A combined concentration of 10% to 80% w/w;
Low surface tension; and
No polymeric film-forming compound.

A competitor using only one of the two emollients could avoid literal infringement of claim 1. A competitor using a polymeric film former could also avoid literal infringement, although the doctrine of equivalents could become relevant depending on the formulation and prosecution history.

What is the significance of the surface-tension limitation?

The surface-tension limitation is a functional and measurable product limitation. Claim 1 requires a surface tension of 40 dynes/cm or less. Claims 2 and 3 narrow that threshold to 30 dynes/cm or less and 25 dynes/cm or less.

Claim	Surface-tension requirement
1	40 dynes/cm or less
2	30 dynes/cm or less
3	25 dynes/cm or less

Surface tension is material because nail penetration depends in part on wetting behavior. A formulation that contains the listed excipients but has surface tension above 40 dynes/cm may fall outside claim 1.

The measurement method can become important in litigation. The patent owner would need to establish the relevant test conditions, temperature, instrument, sample preparation, and reproducibility. A generic developer could seek a design-around through a formulation with the same broad ingredient classes but a surface tension above the claimed threshold.

Which dependent claims cover the commercial 10% formulation?

Claims 5, 9, 12, and 16 expressly recite 10% efinaconazole, but they differ in the additional limitations they impose.

Claim	Key added limitations
5	Efinaconazole at 10%
9	Claim 8 limitations plus efinaconazole at 10%
12	Claim 11 limitations plus efinaconazole at 10%
16	Claim 15 limitations plus efinaconazole at 10%

Claims 8, 9, 11, 12, 15, and 16 are commercially significant because they require the more specific excipient profile:

Diisopropyl adipate at 8% to 15%;
C12-15 alkyl lactate at 8% to 15%;
Ethanol at least 40% w/w; and, depending on the claim,
Cyclomethicone at 2% to 15%; or
An antioxidant.

Claims 9 and 16 are particularly focused on a 10% efinaconazole formulation with the two named emollients and ethanol at least 40%. Claim 9 also inherits the cyclomethicone limitation from claim 8. Claim 16 inherits the ethanol and emollient limitations from claim 15 but does not expressly add the narrower cyclomethicone range from claim 7.

What formulations are protected by US 10,828,369?

The claims cover formulations with the following principal design:

Formulation characteristic	Protected range
Efinaconazole	0.0001% to 30%
Preferred efinaconazole range	2% to 15%
Commercially focused strength	10%
Ethanol	10% to 80%
Narrow ethanol limitations	At least 15%, at least 25%, or at least 40%
Cyclomethicone	1% to 40%
Narrow cyclomethicone range	2% to 15%
Diisopropyl adipate	8% to 15% in narrower claims
C12-15 alkyl lactate	8% to 15% in narrower claims
Antioxidant	0.001% to 0.5%
Surface tension	40 dynes/cm or less, with narrower claims at 30 or 25 dynes/cm
Film former	Excluded

The claims are not limited to the exact commercial excipient percentages unless a narrower dependent claim is asserted. A formulation can therefore present literal infringement risk even if its proportions differ from the marketed product, provided the formulation remains within the claimed ranges.

What are the strongest and weakest claim features?

Strongest features

The strongest protection is the cumulative combination of the following limitations:

Efinaconazole;
Both diisopropyl adipate and C12-15 alkyl lactate;
Cyclomethicone;
Ethanol;
Low surface tension; and
Absence of a polymeric film former.

This combination can create a meaningful barrier against a copycat formulation that reproduces the commercial product’s basic excipient system.

The 10% claims are also commercially important because they align with the approved Jublia strength. Claims 9, 12, and 16 provide multiple dependent-claim routes to the same commercial concentration with different additional limitations.

Weaker features

The broad concentration ranges may create prior-art vulnerability if earlier publications disclose efinaconazole solutions containing overlapping concentrations of ethanol, cyclomethicone, and emollients.

The “no polymeric film forming compound” limitation narrows the claim but may also provide a clear design-around. A competitor could evaluate a polymeric film-forming system, a different wetting agent, a different emollient pair, or a formulation with surface tension above the claimed threshold.

The surface-tension limitation can create proof complexity. The patent holder must demonstrate that the accused product satisfies the numerical threshold using a legally acceptable and technically reproducible method.

How do the claims affect generic efinaconazole entry?

A generic or authorized-generic applicant could face several distinct issues:

Product composition. The proposed formulation may contain the same excipient classes and fall within the concentration ranges.
Surface tension. The proposed product may satisfy the low-surface-tension limitation even if its label does not disclose that property.
Method of use. The approved use for onychomycosis may implicate separately listed method-of-use patents.
Regulatory certification. A generic applicant may need to address patents listed for the reference product in the FDA Orange Book through a Paragraph IV certification or another statutory pathway.[2]
Patent-term timing. FDA approval, marketing exclusivity, and patent expiration are separate legal events.

An ANDA applicant could avoid literal infringement by changing one required element, such as replacing one of the named emollients, using a different silicone, incorporating a polymeric film former, or formulating above the claimed surface-tension threshold. Those changes could affect nail penetration, drying, stability, tolerability, or bioequivalence.

What is the Orange Book status of efinaconazole and Jublia?

Jublia was approved by FDA in 2014 under NDA 203567 as efinaconazole topical solution, 10%.[1] The Orange Book identifies patents and regulatory exclusivity associated with approved drug products, but the patent text alone does not establish which patents are currently listed, delisted, expired, or subject to an active Paragraph IV certification.[2]

US Patent 10,828,369 should therefore be analyzed separately from:

The FDA-approved product label;
Orange Book patent listings;
Any patent-use codes;
Any later-issued continuation patents;
Any terminal disclaimer;
Any patent term adjustment or extension; and
Any litigation or settlement affecting generic entry.

The claims supplied for analysis do not themselves establish an Orange Book listing, a Paragraph IV challenge, a Hatch-Waxman lawsuit, or a settlement agreement.

When does US Patent 10,828,369 lose exclusivity?

The patent issued on November 10, 2020. Its expiration date cannot be calculated reliably from the claim text alone because the controlling date depends on the patent family’s earliest effective nonprovisional filing date, any terminal disclaimer, patent-term adjustment, and other USPTO term data.

Patent expiration is distinct from FDA market exclusivity. The relevant commercial date is the latest enforceable patent or regulatory exclusivity barrier applicable to the proposed generic product, not necessarily the expiration date of US 10,828,369 alone.

What is the patent landscape for efinaconazole?

The efinaconazole landscape has several layers:

Active-ingredient patents

Earlier patents may cover efinaconazole itself, stereochemical forms, pharmaceutical salts, intermediates, or methods of synthesis. Those rights are separate from the formulation claims in US 10,828,369.

Formulation patents

US 10,828,369 is a formulation patent. Its commercial value is tied to the excipient combination and physical properties of the solution rather than to molecular exclusivity.

Other formulation patents may address:

Solubilization systems;
Nail penetration;
Volatile solvents;
Silicone components;
Antioxidants;
Applicator systems;
Stability;
Low-viscosity solutions; and
Alternative non-film-forming dosage forms.

Method-of-use patents

Method claims may cover topical treatment of onychomycosis, dosing schedules, application frequency, treatment duration, or particular patient populations. A formulation may avoid one formulation patent but still face method-of-use exposure.

Manufacturing and process patents

Process patents may cover mixing order, temperature control, dissolution of efinaconazole, removal of particulates, packaging, or manufacturing methods that improve stability. These patents generally create a different risk profile because infringement depends on the accused manufacturing process, not merely on the final product.

How strong is the patent estate represented by US 10,828,369?

On the supplied claims alone, the estate has moderate formulation strength.

Its advantages are:

Direct alignment with the 10% commercial strength;
Multiple dependent claims directed to commercially plausible compositions;
Coverage of both composition and measurable surface tension;
Inclusion of a negative limitation excluding polymeric film formers; and
Open “comprising” language that permits additional excipients.

Its limitations are:

Dependence on a specific four-component excipient architecture;
Potential design-around through alternative emollients or silicones;
Potential prior-art issues from overlapping formulation disclosures;
Measurement disputes over surface tension; and
No apparent claim to the efinaconazole molecule itself.

The patent is strongest against a formulation that copies the active ingredient, solvent system, silicone, named emollients, low surface tension, and non-film-forming design. It is weaker against products built around a different excipient strategy.

Which companies are challenging efinaconazole exclusivity?

The supplied claim text contains no information identifying an ANDA filer, Paragraph IV certification, patent litigation, or settlement agreement. Those events cannot be established from US Patent 10,828,369 itself.

For commercial diligence, the relevant records are FDA Orange Book entries, FDA ANDA approvals, district-court complaints, Federal Circuit decisions, USPTO assignment records, and any public settlement filings.[2-5]

Key Takeaways

US Patent 10,828,369 is a formulation patent for topical efinaconazole nail solutions.
Claim 1 requires efinaconazole, ethanol, cyclomethicone, both diisopropyl adipate and C12-15 alkyl lactate, low surface tension, and no polymeric film-forming compound.
Claims 9, 12, and 16 are the most commercially relevant dependent claims because they focus on 10% efinaconazole formulations.
The patent does not broadly cover all efinaconazole products or the efinaconazole molecule.
A generic developer may design around the claims by changing the emollient system, silicone, surface tension, or film-forming strategy.
Exact patent expiration, Orange Book listing status, Paragraph IV activity, litigation, and settlement status require the patent-family and FDA records, not the claim text alone.
The principal commercial risk is formulation copying that reproduces the Jublia-type excipient system.

FAQs

Does US Patent 10,828,369 cover Jublia?

The claims appear directed to the same general type of 10% efinaconazole nail solution marketed as Jublia, but infringement requires confirmation of the marketed product’s full composition, surface tension, and absence of a polymeric film-forming compound.

Can a generic use 10% efinaconazole and avoid this patent?

Yes. A 10% efinaconazole product may avoid literal infringement if it omits a required ingredient, falls outside a claimed concentration range, exceeds the surface-tension threshold, or contains a polymeric film-forming compound. The resulting product may face other patents or regulatory requirements.

Is a formulation with only diisopropyl adipate covered?

Not literally by claim 1 if it lacks C12-15 alkyl lactate. The claim requires the combined presence of diisopropyl adipate plus C12-15 alkyl lactate.

Does the patent cover an efinaconazole cream or gel?

The claims require a solution. A cream or gel would generally fall outside the literal scope of the supplied claims, although other patents could cover those dosage forms.

Does the patent cover the method of treating onychomycosis?

The supplied claims are composition claims. They do not independently claim a treatment method, dosing regimen, patient population, or treatment duration.

References

U.S. Food and Drug Administration. (2014). Jublia (efinaconazole) topical solution, 10%: Prescribing information.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, Orange Book.
United States Patent and Trademark Office. (2020). U.S. Patent No. 10,828,369.
U.S. Food and Drug Administration. (n.d.). Hatch-Waxman amendments and abbreviated new drug applications.
United States Patent and Trademark Office. (n.d.). Patent Center: Patent and application prosecution records.

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	JUBLIA	efinaconazole	SOLUTION;TOPICAL	203567-001	Jun 6, 2014	AB	RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial	Y				⤷ 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

Details for Patent: 10,828,369

Which drugs does patent 10,828,369 protect, and when does it expire?

Summary for Patent: 10,828,369