United States Patent 8,936,800: Scope, Claims, Expiration, and Patent Landscape for Adapalene/Benzoyl Peroxide Gel

United States Patent No. 8,936,800 protects an aqueous topical acne gel combining adapalene, benzoyl peroxide, and a defined polymeric gelling system. The claims are composition, treatment-method, and container-product claims. The patent is directed to formulations corresponding broadly to Epiduo and related adapalene/benzoyl peroxide products.

The principal infringement risk arises when a product contains all of the following within the claimed ranges:

Adapalene at 0.05% to 1% by weight;
Dispersed benzoyl peroxide at 2.5% to 5% by weight; and
Acrylamide sodium acryloyldimethyltaurate/isohexadecane/polysorbate 80 at 2% to 5% by weight.

The nominal patent expiration date is June 22, 2027, based on the earliest claimed priority date and the 20-year patent term, before any patent-term adjustment or patent-term extension analysis.

What does U.S. Patent 8,936,800 protect?

U.S. Patent 8,936,800 protects a specific aqueous gel architecture rather than every adapalene and benzoyl peroxide product. The patent requires the combination of active ingredients and the identified gelling agent within specified weight percentages.

Claim	Claim type	Principal protected subject matter
1	Composition	Physiologically acceptable aqueous gel containing adapalene, benzoyl peroxide, and the specified polymeric gelling agent
2	Method of treatment	Treating common acne by administering the claimed aqueous gel
3	Product/container	A container containing the claimed aqueous gel

The patent’s claim scope is narrower than the general concept of combining adapalene and benzoyl peroxide. A competing product that uses a different gelling system, falls outside the claimed concentration ranges, or does not use an aqueous gel may avoid literal infringement of claim 1.

How should the active-ingredient limitations be interpreted?

Claim 1 requires anti-acne actives "consisting of" adapalene and benzoyl peroxide. The wording has several consequences.

First, the claim requires benzoyl peroxide at 2.5% to 5% by weight. A formulation containing 2.5% benzoyl peroxide is within the literal range. A formulation containing 2.49% is outside the literal numerical range, subject to possible doctrine-of-equivalents arguments.

Second, the claim requires adapalene at 0.05% to 1% by weight, or an acceptable salt thereof. Commercial acne formulations generally use adapalene rather than an adapalene salt. The claim language nevertheless attempts to cover both the neutral active and pharmaceutically acceptable salt forms.

Third, "and/or" makes the adapalene limitation broad within the claimed class. The claim is directed to adapalene and/or its acceptable salts together with benzoyl peroxide. It does not authorize addition of another anti-acne active without potential claim-scope consequences because "consisting of" is closed transitional language for the anti-acne active component.

The claim does not require a particular adapalene particle size, manufacturing process, preservative, humectant, pH, package type, or dosing schedule unless those limitations appear in an unprovided dependent claim.

What does the gelling-agent limitation cover?

The gelling agent is identified by its full chemical and formulation description:

"Acrylamide sodium acryloyldimethyltaurate/isohexadecane/polysorbate 80."

This material is a preassociated polymeric thickening system commonly used in topical formulations. It is commercially associated with products such as Simulgel EG or related acrylamide-based inverse-emulsion gelling systems, depending on supplier and grade.

The claim requires the material at 2% to 5% by weight of the total aqueous gel composition. The limitation is commercially significant because many generic developers can formulate adapalene and benzoyl peroxide using alternative rheology systems, including carbomers, acrylates/C10-30 alkyl acrylate crosspolymers, cellulose derivatives, or other polymeric thickeners.

A formulation using 0.5% of the claimed polymeric system would be outside the literal 2% to 5% range. A formulation using 2% of the material would fall within the range. The percentage is calculated against the total gel composition, not merely the water phase or the polymer concentrate.

What are the infringement elements for each claim?

Claim 1: Composition infringement

A potentially infringing composition must contain each claimed element:

A physiologically acceptable aqueous gel;
Adapalene or an acceptable adapalene salt at 0.05% to 1%;
Dispersed benzoyl peroxide at 2.5% to 5%; and
The specified acrylamide/sodium acryloyldimethyltaurate/isohexadecane/polysorbate 80 gelling agent at 2% to 5%.

The claim is best understood as an all-elements claim. Omitting one required limitation generally defeats literal infringement. The phrase "physiologically acceptable" likely functions as a formulation-suitability limitation rather than an independent technical barrier for ordinary pharmaceutical products.

Claim 2: Method-of-treatment infringement

Claim 2 covers administering the same formulation to a subject in need of treatment for common acne. A commercial product label that instructs users to apply the formulation for acne treatment could be relevant to induced-infringement analysis if the underlying composition falls within claim 2’s formulation limitations.

The method claim does not appear to require a particular frequency, dose, treatment duration, age group, or severity of acne. The method is therefore broader than a claim limited to a specific once-daily regimen, but it remains dependent on use of the claimed formulation.

Claim 3: Container-product infringement

Claim 3 covers a product comprising:

A container; and
The claimed aqueous gel contained within that container.

The container limitation is commercially important because ordinary tubes, pumps, jars, or other topical-product packages could satisfy it if they contain a composition meeting the formulation limitations. The claim does not appear to require a specialized delivery device or a particular container material.

Claim 3 is unlikely to provide a meaningful design-around opportunity where the formulation itself falls within claim 1. Changing from a tube to a pump, for example, would not avoid the claim if the product still contains the claimed gel.

When does U.S. Patent 8,936,800 lose exclusivity?

The nominal expiration date is June 22, 2027.

Event	Date or status
Earliest claimed priority	June 22, 2007
U.S. patent grant	February 3, 2015
Nominal 20-year expiration	June 22, 2027
Patent-term adjustment	Must be added if reflected on the issued patent
Patent-term extension	No extension is established from the claim language alone
Post-expiration status	Claims cease to block conduct occurring after expiration, subject to applicable regulatory and litigation rules

The patent’s enforceable expiration date should be determined from the issued patent’s term-adjustment data and any terminal disclaimer. A patent may also coexist with later-expiring patents covering improved concentrations, delivery systems, or manufacturing processes.

What is the Orange Book status of U.S. Patent 8,936,800?

The patent is associated with the proprietary adapalene/benzoyl peroxide acne-gel product line marketed by Galderma, including the Epiduo product family. Epiduo was approved by the FDA under NDA 022320 as a topical gel containing adapalene 0.1% and benzoyl peroxide 2.5%.[2]

The claimed ranges encompass the marketed 0.1%/2.5% formulation:

Product characteristic	Epiduo-type formulation	Claim 1 range
Adapalene	0.1%	0.05% to 1%
Benzoyl peroxide	2.5%	2.5% to 5%
Dosage form	Aqueous topical gel	Required
Gelling system	Claimed polymer system	2% to 5% required

The Orange Book listing, if maintained for the relevant NDA, would create a statutory patent-certification issue for an ANDA applicant seeking approval of a therapeutically equivalent product. Orange Book listing does not itself establish infringement. It determines the regulatory pathway for patent certifications and can trigger the Hatch-Waxman litigation framework.

How do Paragraph IV challenges affect generic entry?

An ANDA applicant seeking approval before the patent expires may submit a Paragraph IV certification asserting that the patent is invalid, unenforceable, or will not be infringed. If the NDA holder receives notice and files suit within the statutory period, FDA approval may be subject to a 30-month stay, subject to the statutory exceptions and court developments.[3]

For this patent, an ANDA applicant could pursue several strategies:

Strategy	Technical approach	Patent risk
Paragraph III certification	Accept patent expiry and defer approval	Low litigation risk; launch generally after expiration
Paragraph IV certification	Challenge validity or noninfringement	High litigation and launch risk
Formulation design-around	Use a different gelling agent or concentration	May avoid literal composition infringement
Concentration design-around	Move outside one or more claimed ranges	Requires stability, efficacy, and equivalence support
505(b)(2) pathway	Seek approval with reliance on existing data while changing formulation or indication	Regulatory and patent analysis differs from a conventional ANDA

A product containing adapalene 0.1%, benzoyl peroxide 2.5%, and the claimed polymer at 2% to 5% presents the clearest infringement risk. A product using the same actives but a different polymer system presents a materially different patent position, although later patents or doctrine-of-equivalents theories may remain relevant.

What validity issues could affect the patent?

The principal validity issues are likely to concern obviousness, written description, enablement, indefiniteness, and claim construction.

Obviousness

Adapalene, benzoyl peroxide, aqueous topical gels, and polymeric gelling agents were individually known in the acne field. A challenger could argue that combining known actives in an aqueous gel with a known gelling system would have been obvious.

The patent owner would likely rely on formulation-specific evidence, including stability, compatibility, reduced degradation, improved dispersion, acceptable rheology, tolerability, or unexpected performance. The strength of that defense depends on the patent specification and experimental data, not on the claim text alone.

Written description and enablement

The broad numerical ranges, especially adapalene up to 1% and benzoyl peroxide up to 5%, could invite written-description or enablement scrutiny if the specification does not support the full range. The same issue applies to the broad "and/or" language covering adapalene and salts.

Indefiniteness and claim construction

Potential construction disputes could involve:

The meaning of "dispersed benzoyl peroxide";
Whether the identified gelling agent must be present as a preformed commercial blend;
The meaning of "physiologically acceptable";
Whether the active ingredient language excludes every additional anti-acne ingredient or only additional actives within the composition’s anti-acne category; and
The method claim’s meaning of "administering" in a topical context.

These issues could materially affect litigation outcomes.

What other patents compete with U.S. Patent 8,936,800?

The relevant patent estate is broader than this single patent. A complete freedom-to-operate review should separate patents into four groups.

Foundational adapalene patents

Earlier patents protect adapalene, its use in acne, and formulations containing the retinoid. Many such patents have expired or are no longer the primary barrier to generic entry.

Combination-product patents

Patents covering adapalene combined with benzoyl peroxide are more directly relevant to Epiduo-type products. These may claim composition ranges, stability systems, packaging, or methods of treating acne.

Formulation and delivery patents

Later patents may cover:

Higher-strength adapalene products, including 0.3%;
Particular polymer systems;
Water-in-oil or oil-in-water structures;
Encapsulated or stabilized benzoyl peroxide;
Pump or tube packaging;
Reduced-irritation formulations; and
Manufacturing methods that preserve benzoyl peroxide activity.

A generic product may avoid U.S. Patent 8,936,800 and still face a later-expiring formulation patent.

Method-of-use patents

Method claims may cover acne treatment, treatment frequency, patient populations, or combination use with other dermatological therapies. A product label can create a separate patent issue even where the composition claim is avoided.

Which companies are relevant to the competitive landscape?

Galderma is the principal branded sponsor associated with Epiduo and related acne products. Generic competition includes companies that have developed or marketed adapalene/benzoyl peroxide topical gels through ANDA pathways.

The competitive analysis should distinguish:

The branded Epiduo and Epiduo Forte products;
Authorized generics or licensed products;
ANDA-approved adapalene/benzoyl peroxide gels;
Over-the-counter benzoyl peroxide products; and
Standalone adapalene products.

Benzoyl peroxide products alone do not practice the combination claims. Standalone adapalene products also do not meet the active-ingredient limitations requiring benzoyl peroxide.

What is the commercial exposure from this patent?

The patent’s commercial value is concentrated in the combination-gel segment. It does not block all topical retinoids, all benzoyl peroxide products, or all acne gels.

The highest-risk product profile is:

Adapalene 0.1%;
Benzoyl peroxide 2.5%;
Aqueous gel;
The specified gelling system at 2% to 5%; and
A topical acne indication.

The commercial barrier decreases when a competitor changes the gelling agent or moves outside the claimed ranges. The regulatory burden may then increase because the alternative formulation must demonstrate pharmaceutical equivalence, bioequivalence or other applicable requirements, stability, microbial quality, and comparable clinical performance.

Key Takeaways

U.S. Patent 8,936,800 claims an aqueous adapalene/benzoyl peroxide gel, its acne-treatment use, and a container containing the gel.
The key technical limitation is the specific acrylamide sodium acryloyldimethyltaurate/isohexadecane/polysorbate 80 gelling agent at 2% to 5%.
Epiduo-type 0.1% adapalene/2.5% benzoyl peroxide formulations fall within the active-ingredient ranges.
A formulation using a different gelling system may avoid literal infringement of claim 1.
The nominal expiration date is June 22, 2027, subject to patent-term adjustment and any applicable terminal disclaimer.
Paragraph IV risk is highest for an ANDA product duplicating the claimed composition and label.
Avoiding this patent does not eliminate exposure to later formulation, packaging, manufacturing, or method-of-use patents.

FAQs

Does U.S. Patent 8,936,800 cover Epiduo Forte?

The claimed adapalene range extends to 1% and therefore encompasses the 0.3% adapalene concentration used in Epiduo Forte, assuming the product also contains benzoyl peroxide and the claimed gelling agent within the specified ranges.

Can a generic use adapalene 0.1% and benzoyl peroxide 2.5% without infringing?

Yes, potentially. The active concentrations alone do not determine infringement. The product must also be an aqueous gel containing the specified gelling agent at 2% to 5%, along with the other claim limitations.

Does changing the package avoid claim 3?

Changing the package does not avoid claim 1. It may affect claim 3 only if the resulting product no longer satisfies the container limitation, but ordinary commercial packaging would generally remain capable of meeting that limitation.

Are benzoyl peroxide-only products covered by this patent?

No. The claims require both benzoyl peroxide and adapalene or an acceptable adapalene salt.

Does patent expiration automatically permit immediate generic marketing?

Patent expiration removes the patent barrier, but FDA approval, applicable exclusivity periods, regulatory requirements, and other unexpired patents can still affect launch timing.

References

United States Patent No. 8,936,800. (2015). Aqueous gel composition comprising adapalene and benzoyl peroxide. United States Patent and Trademark Office.
U.S. Food and Drug Administration. (2008). Epiduo (adapalene and benzoyl peroxide) gel, 0.1%/2.5%: Prescribing information. FDA.
U.S. Food and Drug Administration. (2023). Approved drug products with therapeutic equivalence evaluations. FDA.

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
France	01 16747	Dec 21, 2001

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	1458369	⤷ Start Trial	CA 2008 00029	Denmark	⤷ Start Trial
European Patent Office	1458369	⤷ Start Trial	08C0024	France	⤷ Start Trial
European Patent Office	1458369	⤷ Start Trial	SPC/GB10/005	United Kingdom	⤷ Start Trial
European Patent Office	1458369	⤷ Start Trial	C01458369/01	Switzerland	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 8,936,800

Summary for Patent: 8,936,800