US Patent 9,980,983: Scope, Claims, Expiration, and Seborrheic Keratosis Patent Landscape

US Patent No. 9,980,983 protects methods of treating seborrheic keratosis with a topical composition containing approximately 40% w/w stabilized hydrogen peroxide. Its broadest claim is a method-of-treatment claim. The patent does not independently claim every 40% hydrogen peroxide composition, but it creates infringement risk when a product is used to treat seborrheic keratosis and contains the specified concentration and stabilizer technology.

The patent covers formulation performance parameters, dosing schedules, applicators, excipients, lesion debridement, and treatment without another active ingredient or therapeutic intervention. The commercial product most closely associated with the patent was Eskata, a 40% hydrogen peroxide topical solution developed by Aclaris Therapeutics and approved by the FDA in 2017.[1]

What does US Patent 9,980,983 protect?

The patent protects a method comprising topical administration of a composition containing approximately 40% w/w stabilized hydrogen peroxide to a human with seborrheic keratosis.

Claim 1 is the commercially significant independent claim. It requires four core elements:

Claim element	Requirement
Patient	Human
Condition	Seborrheic keratosis
Route	Topical administration
Active composition	About 40% w/w stabilized hydrogen peroxide
Stabilization technology	Stannate, sodium pyrophosphate, organophosphonate, nitrate, phosphoric acid, colloidal silicate, or a combination

The claim is not limited to one brand, one container, one formulation form, or one administration schedule. It can reach a solution or gel and does not require a particular applicator unless a dependent claim is being asserted.

The claim is also not limited to treatment of a particular lesion size, body site, patient age, or severity of seborrheic keratosis. A product that satisfies the composition limitations and is used for the claimed indication may fall within the claim regardless of whether it is marketed under the same brand or uses a different delivery device.

How broad is claim 1 of US 9,980,983?

Claim 1 has broad use-based coverage but several important technical limitations.

Concentration limitation

The composition must contain “about 40% w/w” stabilized hydrogen peroxide. The term “about” creates a range rather than an exact 40.00% threshold. The permissible range would likely depend on the patent specification, prosecution history, analytical method, and ordinary pharmaceutical formulation practice.

A product containing materially less or more hydrogen peroxide may avoid literal infringement, although the doctrine of equivalents could remain relevant if the concentration performs substantially the same function in substantially the same way.

Stabilizer limitation

The hydrogen peroxide must be stabilized using at least one member of the listed group:

Stannate
Sodium pyrophosphate
Organophosphonate
Nitrate
Phosphoric acid
Colloidal silicate

The list is a Markush group. A formulation using one listed stabilizer can satisfy the limitation. The claim does not require that the listed compound be the only stabilizer or the dominant stabilizer.

A competing formulation that uses a different stabilizer may have a stronger non-infringement position, subject to claim construction and equivalents analysis. A formulation that combines a listed stabilizer with another stabilizing system remains within the literal scope if the remaining elements are met.

Treatment limitation

The composition must be topically administered to treat seborrheic keratosis. Mere manufacture or sale of a composition may not directly infringe claim 1 without the required treatment use. Commercial labeling, promotional materials, training materials, product instructions, and distribution channels could be relevant to induced-infringement analysis.

What do claims 2 through 25 add?

The dependent claims create narrower positions covering dosing, formulation characteristics, packaging, administration, and treatment technique.

Claims	Subject matter	Commercial or litigation significance
2	One administration	Covers single-treatment protocols
3-4	Two administrations, with the second about three weeks later	Tracks the Eskata dosing regimen
5	Surface tension of about 42 to 55 mN/m at 37°C	Targets wetting and lesion-contact behavior
6	Stability for specified periods at 5°C, 30°C, or 40°C	Adds shelf-life and accelerated-stability limitations
7	Mean steady-state release of 1,000 to 1,750 µg/cm²/hour between 0.5 and 4 hours	Covers hydrogen peroxide release kinetics
8	Mean redox potential of about 415 to 430 mV	Adds electrochemical formulation performance
9	pH of about 3.5 to 4	Covers acidic formulation conditions
10-11	Solution or gel	Covers two principal dosage forms
12	Specified applicators	Covers sponge, swab, brush, roller, gauze, glove, pen, doe-foot, and related devices
13-17	Frangible ampoule applicator with filter and controlled dispensing	Covers single-use packaging and delivery mechanics
18-22	Surface-tension agent, alcohol, stabilizer, gelling agent, or excipient	Adds formulation subcombinations
23	Debridement before or during treatment	Covers lesion-preparation procedures
24	No additional active agent needed	Supports single-active-agent treatment
25	No additional therapeutic intervention needed	Covers treatment without another therapeutic procedure

Claims 2 and 3 are alternative regimen claims. Claim 4 narrows claim 3 by requiring the second administration approximately three weeks after the first. This timing corresponds closely to the FDA-approved Eskata instructions.[1]

Claims 5 through 9 are measurable product-performance claims. They may be useful when the formulation composition is difficult to determine from a label but can be characterized through laboratory testing.

Claims 13 through 17 are particularly important for single-use products. They require a specific architecture: a frangible ampoule inside an applicator body, a hub, a tip, and a filter between the ampoule and tip. Claims 14 and 16 add operational steps involving squeezing force and rupture of the ampoule.

What formulations are protected by US 9,980,983?

The patent reaches both solutions and gels containing approximately 40% stabilized hydrogen peroxide.

Solution formulations

Claim 10 expressly covers a solution. Eskata was approved as a topical solution containing 40% hydrogen peroxide.[1] A competing solution using the listed stabilizers and marketed for seborrheic keratosis would face the clearest literal infringement risk.

Gel formulations

Claim 11 covers a gel. A gel product could infringe even if its viscosity, rheology, excipient profile, or application technique differs from a commercial solution, provided the product satisfies claim 1 and the gel limitation.

Excipients and formulation modifiers

Claims 18 through 22 cover formulations that include:

Surface-tension modifiers
Alcohol
Additional stabilizer
Gelling agent
Excipient

These claims do not require every listed additive. Each dependent claim adds one category to the claim 1 composition.

The patent therefore reaches a wide formulation space. However, the claims do not appear to cover every hydrogen peroxide formulation used in dermatology. They are tied to the approximate 40% concentration, stabilization group, and seborrheic keratosis treatment method.

What does the applicator coverage protect?

Claims 12 through 17 extend the patent beyond the liquid composition and into administration hardware.

The broad applicator claim, claim 12, identifies numerous conventional application tools, including swabs, brushes, foam-tipped sticks, woven and non-woven fabrics, rollers, gauze, gloves, pen-type applicators, and flocked or doe-foot applicators.

Claims 13 through 17 are narrower and more technically specific. The required combination includes:

A frangible ampoule containing the composition.
An applicator body containing the ampoule.
An applicator hub in fluid communication with the body.
A tip at the proximal end of the hub.
A filter between the ampoule and tip.

The device limitations are incorporated into a method claim. The claim is therefore directed to administering the composition using the specified device, rather than claiming the applicator as a standalone apparatus.

A design-around could use a bottle, pump, tube, prefilled syringe, dropper, or non-frangible container. That approach could avoid claims 13 through 17 while remaining exposed to claim 1 and other composition or method claims.

When does US Patent 9,980,983 lose exclusivity?

The patent was granted on May 29, 2018. Its underlying priority and filing chain indicate a nominal 20-year patent term extending into 2034, subject to the official USPTO patent-term-adjustment calculation and any applicable terminal disclaimer.[2]

Event	Date or period
Patent grant	May 29, 2018
Patent type	Utility patent
Nominal term basis	20 years from the earliest effective nonprovisional filing
Expected term endpoint	2034, subject to USPTO term calculation
Regulatory approval of Eskata	December 2017
FDA product withdrawal from commercial availability	2019

Patent expiration and FDA exclusivity are separate rights. The patent may remain enforceable after the branded product is discontinued. Conversely, discontinuation of Eskata does not automatically cancel the patent or eliminate patent-based barriers to a later entrant.

The patent may also qualify for patent-term adjustment based on USPTO prosecution delays. The controlling expiration date is the term shown in the USPTO patent record, not simply the grant date plus 20 years.[2]

What is the FDA and Orange Book status of Eskata?

The FDA approved Eskata, a 40% hydrogen peroxide topical solution, under NDA 210361 in December 2017 for the treatment of raised seborrheic keratoses in adults.[1]

The FDA labeling described application to individual lesions, with a second treatment approximately three weeks after the first when needed. That regimen corresponds to claims 3 and 4 of US 9,980,983.

Aclaris later discontinued commercial availability of Eskata in 2019 because of limited market demand.[3] Commercial discontinuation is distinct from a finding that the product was unsafe or ineffective. The FDA Orange Book distinguishes discontinued products from withdrawn approvals and lists patent information separately from marketing status.[4]

Regulatory issue	Status
Active ingredient	Hydrogen peroxide
Strength	40% w/w
Dosage form	Topical solution
Indication	Raised seborrheic keratoses in adults
NDA	210361
Initial approval	2017
Commercial status	Discontinued
Generic approval	No widely established ANDA-based generic market for the product
Patent relevance	Continues independently of commercial sales

Are there Paragraph IV challenges to US 9,980,983?

A Paragraph IV certification is made by an ANDA applicant asserting that an Orange Book-listed patent is invalid, unenforceable, or will not be infringed. It is not created by patent expiration, product discontinuation, or ordinary off-label use.

The available public record does not establish a major litigated Paragraph IV challenge directed specifically to US 9,980,983. The absence of a visible Paragraph IV dispute does not mean that the patent is immune from challenge. It means that no significant ANDA litigation record is identified for this patent in the principal public sources reviewed.

Potential ANDA exposure would be limited by several commercial factors:

Eskata was discontinued.
The patient population is relatively narrow.
A generic applicant would need to establish substitutability or an acceptable labeling strategy.
The reference product’s discontinued commercial status complicates commercial development.
Method-of-use claims can create labeling and induced-infringement issues even where formulation similarity is established.

A generic applicant could pursue a section viii carve-out for a patented indication only if the remaining approved labeling and product use were legally and regulatorily viable. Because the patent’s central claim is directed to treating seborrheic keratosis, a complete carve-out could remove the core commercial use.

Which companies are challenging the patent landscape?

No major public patent challenge is established against US 9,980,983 based on the patent, FDA, Orange Book, and readily identifiable litigation records. The relevant competitive landscape is therefore less a conventional branded-versus-generic dispute and more a question of whether a new sponsor can develop:

A materially different hydrogen peroxide concentration.
A formulation using a non-listed stabilizer.
A different indication or treatment protocol.
A non-infringing delivery system.
A product that avoids the patented seborrheic keratosis use.

Companies developing topical lesion treatments could also avoid direct overlap by using a different active ingredient or a different mechanism, such as cryotherapy, curettage, electrosurgery, keratolytic agents, retinoid-based products, or other lesion-directed therapies. Those products would not necessarily implicate the hydrogen peroxide claims.

How strong is the patent estate for seborrheic keratosis treatment?

US 9,980,983 has a strong claim structure against a product that closely replicates the Eskata profile. The strongest overlap occurs where a competitor uses all of the following:

Approximately 40% hydrogen peroxide.
A listed stabilizer.
Topical treatment of seborrheic keratosis.
A one- or two-treatment regimen.
A pH around 3.5 to 4.
The specified solution or gel format.
A listed applicator or frangible ampoule system.

Its strength is weaker against products that depart from the core claim architecture. The principal design-around variables are concentration, stabilizer chemistry, indication, dosage form, and delivery system.

Primary patent strengths

Claim 1 is not limited to the Eskata trademark or a single manufacturer.
The listed stabilizer group covers multiple chemical approaches.
The “about 40%” language may capture commercially realistic concentration variation.
The claim reaches both solutions and gels through dependent claims.
Performance claims provide additional infringement theories when composition disclosure is incomplete.
The treatment claim can implicate branded labeling and induced-use theories.

Principal validity and enforcement pressure points

The 40% hydrogen peroxide concept may face written-description and enablement scrutiny if asserted broadly across all listed stabilizers and formulation types.
The meaning of “about 40%” may become central to claim construction.
Terms such as “stabilized,” “mean steady state release,” and “mean redox potential” require validated testing methods.
Negative limitations in claims 24 and 25 may create proof and claim-construction issues.
Method claims require proof of the treatment use, not merely composition manufacture.
Applicator claims are narrower and easier to avoid with different packaging.

What patent litigation affects US 9,980,983?

No major reported infringement action or Paragraph IV case is established as a material current dispute involving this patent. The absence of litigation reduces available judicial guidance on:

The scope of “about 40%.”
The meaning of “stabilized hydrogen peroxide.”
The reach of the listed stabilizer group.
The interpretation of “no additional active agent.”
The scope of the three-week dosing limitation.
Whether the performance parameters are inherent or must be expressly met.

The patent remains relevant for freedom-to-operate analysis even without litigation. A company developing a 40% stabilized hydrogen peroxide product for seborrheic keratosis would need a claim chart against the formulation, intended use, labeling, dosing protocol, and delivery device.

What generic launch risks exist?

A generic launch would face three separate risk categories.

Patent risk

A product closely matching Eskata could satisfy claim 1 even if it uses a different brand, package, or manufacturer. The most material patent risk is therefore the core method claim, not only the applicator claims.

Regulatory risk

A sponsor would need to address the FDA pathway for a discontinued topical product and demonstrate the required pharmaceutical equivalence, bioequivalence or equivalent performance, quality attributes, and labeling position.[1,4]

Commercial risk

The commercial opportunity may be limited because Eskata was withdrawn from the market after poor demand. A generic product would need to establish physician adoption, reimbursement, patient demand, and a durable treatment setting.

How does US 9,980,983 compare with competing treatment patents?

US 9,980,983 is narrower than a platform patent covering all hydrogen peroxide dermatology uses, but broader than a patent limited to one formulation or applicator.

Patent category	Typical scope	Relationship to US 9,980,983
Active-ingredient patent	Hydrogen peroxide or another active	9,980,983 is not a basic hydrogen peroxide composition patent
Formulation patent	Concentration, stabilizers, pH, release, stability	9,980,983 incorporates these elements through dependent claims
Method-of-use patent	Treatment of seborrheic keratosis	This is the principal scope of 9,980,983
Device patent	Ampoule, tip, filter, dispensing system	Claims 13-17 add this coverage as part of the treatment method
Regulatory exclusivity	FDA approval-based market protection	Separate from patent rights
Procedure patent	Cryotherapy, curettage, electrosurgery	Generally outside the hydrogen peroxide claim set

What manufacturing and IP barriers remain?

Manufacturing a 40% hydrogen peroxide topical product creates technical barriers separate from patent validity.

The manufacturer must control:

Hydrogen peroxide decomposition.
Stabilizer compatibility.
Container interaction.
Oxygen generation and pressure.
Light and temperature sensitivity.
pH drift.
Dose uniformity.
Applicator compatibility.
Microbial and chemical stability.
Transport and storage conditions.

Claim 6 is important because it links patent coverage to stability outcomes at multiple temperatures. A manufacturer may avoid that dependent claim by failing to meet a specified stability period, but that does not avoid claim 1 if the product otherwise satisfies the concentration, stabilization, and treatment-use limitations.

A different container may reduce exposure to claims 13 through 17, but packaging changes do not eliminate risk under claim 1.

Key Takeaways

US 9,980,983 is primarily a method-of-treatment patent for topical treatment of seborrheic keratosis with approximately 40% stabilized hydrogen peroxide.
Claim 1 is the central commercial claim and requires a listed stabilizer, not merely hydrogen peroxide.
Claims 2 through 4 cover single and two-treatment regimens, including a second treatment about three weeks later.
Claims 5 through 9 protect formulation performance parameters including surface tension, stability, release rate, redox potential, and pH.
Claims 13 through 17 cover a frangible ampoule applicator with a filter and controlled dispensing.
Eskata was FDA-approved in 2017 and later discontinued commercially, but discontinuation does not by itself terminate patent rights.
The patent’s nominal term extends into 2034, subject to the official USPTO patent-term calculation.
No material public Paragraph IV or infringement litigation is established against US 9,980,983.
The clearest design-around strategies involve changing the hydrogen peroxide concentration, using a non-listed stabilizer, adopting a different indication, or avoiding the claimed applicator architecture.
A new 40% stabilized hydrogen peroxide product labeled for seborrheic keratosis would face substantial literal infringement risk.

FAQs

Does US 9,980,983 claim the Eskata product itself?

No. The patent claims methods of treating seborrheic keratosis and includes dependent limitations directed to formulation properties and an applicator. It does not function as a simple composition claim covering every 40% hydrogen peroxide product.

Can a product avoid the patent by using 39% hydrogen peroxide?

Possibly, but not automatically. The claim requires “about 40%,” and the legal range depends on claim construction, specification disclosure, prosecution history, and analytical evidence.

Does using a different applicator avoid US 9,980,983?

It may avoid claims 13 through 17 and potentially claim 12. It does not avoid claim 1 if the composition and treatment-use limitations remain satisfied.

Is a discontinued FDA product still protected by its patent?

Yes. FDA commercial discontinuation and patent enforceability are separate matters. A patent can remain in force even when the associated product is no longer marketed.

Can a generic use a section viii labeling carve-out?

A carve-out may be difficult if the patented seborrheic keratosis treatment is the principal or only commercially relevant use. The feasibility depends on the proposed labeling, FDA requirements, and the scope of the listed method claims.

References

U.S. Food and Drug Administration. (2017). Eskata (hydrogen peroxide) topical solution, 40%: Prescribing information. FDA.
United States Patent and Trademark Office. (2018). U.S. Patent No. 9,980,983, methods of treating seborrheic keratosis. U.S. Department of Commerce.
Aclaris Therapeutics, Inc. (2019). Corporate communications regarding discontinuation of Eskata commercial operations. Aclaris Therapeutics.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Aclaris	ESKATA	hydrogen peroxide	SOLUTION;TOPICAL	209305-001	Dec 14, 2017		DISCN	Yes	No	⤷ Start Trial	⤷ Start Trial				TREATMENT OF SEBORRHEIC KERATOSES THAT ARE RAISED	⤷ 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	2015249841	⤷ Start Trial
Brazil	112016024630	⤷ Start Trial
Canada	2946568	⤷ Start Trial
China	106659643	⤷ Start Trial
Denmark	3134061	⤷ Start Trial
European Patent Office	3134061	⤷ Start Trial
Spain	2828711	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 9,980,983

Which drugs does patent 9,980,983 protect, and when does it expire?

Summary for Patent: 9,980,983