US Patent 8,808,716 (United States) Scope, Claims, and Patent Landscape
US Patent 8,808,716 is directed to an oil-in-water emulsion aerosol foam composition with a defined aerosol base plus a hydrocarbon propellant load. The independent coverage is narrow in formulation detail and propellant amount, with three claim variants that differ in specific weight-percent levels and which preservative system is used (sorbic acid versus potassium sorbate) while keeping the core emulsion components and propellant window consistent.
What is claimed in US 8,808,716?
1) What is the structural claim scope?
All three claims are composition claims with the same architecture:
- Type: “oil in water emulsion aerosol foam composition”
- Phases: an oil phase and a water phase
- Contains a defined “aerosol base” comprising specific ingredients with specified weight-percent ranges (fixed “about” targets, not broad ranges)
- Contains a hydrocarbon propellant in an amount from about 7 to about 8 grams per 100 grams of aerosol base
The claims are not directed to a method of treating disease, a device, or a manufacturing process in the provided text. The functional novelty is embedded in the formulation, not the therapeutic use.
2) What are the exact aerosol base compositions in claims 1 to 3?
Percentages are weight-%, based on the total weight of the aerosol base.
Claim 1 (sorbic acid system)
- Butylated hydroxytoluene (BHT): about 0.1%
- Ceteareth 12: about 5%
- Light mineral oil: about 6%
- Sorbic acid: about 6%
- Diisopropyl adipate: about 0.4%
- Tazarotene: about 5%
- Citric acid: about 0.1%
- Potassium citrate: about 0.03%
- Water: about 82.80%
- Hydrocarbon propellant: about 7 to about 8 g per 100 g aerosol base
Claim 2 (potassium sorbate system)
- Butylated hydroxytoluene (BHT): about 0.1%
- Ceteareth 12: about 5%
- Light mineral oil: about 6%
- Potassium sorbate: about 0.15%
- Diisopropyl adipate: about 0.2%
- Tazarotene: about 5%
- Citric acid: about 0.1%
- Potassium citrate: about 0.037%
- Water: about 83.31%
- Hydrocarbon propellant: about 7 to about 8 g per 100 g aerosol base
Claim 3 (higher sorbic acid and higher diisopropyl adipate, different oil load)
- Butylated hydroxytoluene (BHT): about 0.1%
- Ceteareth 12: about 5%
- Light mineral oil: about 8%
- Sorbic acid: about 0.40%
- Diisopropyl adipate: about 0.40%? (Your claim text states about 0.40% diisopropyl adipate and about 7% tazarotene? The provided sequence reads: “about 8% sorbic acid about 0.40% diisopropyl adipate about 7% tazarotene about 0.1% citric acid about 0.03% potassium citrate about 0.54% water about 78.83%”. The claim ordering implies sorbic acid about 8% and diisopropyl adipate about 0.40%, tazarotene about 7%, potassium citrate about 0.03%, water 78.83%.)
- Citric acid: about 0.1%
- Potassium citrate: about 0.03%
- Water: about 78.83%
- Hydrocarbon propellant: about 7 to about 8 g per 100 g aerosol base
Key point: Across the three claims, the “engine” components remain consistent: BHT, Ceteareth 12, diisopropyl adipate, tazarotene, citric acid, potassium citrate, and water, with limited variability in light mineral oil, sorbic acid/potassium sorbate choice, and tazarotene level (claims 1 and 2 use about 5%, claim 3 uses about 7% based on your text).
3) What is the propellant limitation?
The only explicitly quantified non-base component is:
- Hydrocarbon propellant: about 7 to about 8 grams per 100 grams of aerosol base
This is a tight dosing constraint. It limits design-around strategies that would otherwise change aerosol performance via propellant loading.
How broad is the patent right?
1) What limits infringement risk because formulation is fully enumerated?
The claims do not recite functional ranges like “a preservative effective amount” or “tazarotene in a therapeutically effective amount.” Instead, they recite aerosol base components with “about X%” weight fractions. This narrows potential infringement to compositions that fall within the “about” tolerance for each listed component.
2) Where the independent scope appears narrowest
The narrowest elements are:
- The combination of specific emulsifier (Ceteareth 12) plus specific oils/esters (light mineral oil and diisopropyl adipate) plus specific actives/preservatives (tazarotene plus citric acid/potassium citrate plus sorbic acid or potassium sorbate) in near-fixed weight percent targets.
- The hydrocarbon propellant loading of 7 to 8 g per 100 g aerosol base.
3) What variability is still arguably permitted
The claims use “about” at single-point percentages and an explicit propellant window. That leaves room for:
- Manufacturing variability and analytical measurement tolerance around each “about X%”
- Small reformulations that keep each ingredient within the “about” interpretation
But the structure still acts like a formula claim: any meaningful departure from one component level increases the design-around probability.
Claim-by-claim breakdown for freedom-to-operate mapping
Claim 1: BHT + Ceteareth 12 + light mineral oil + sorbic acid + diisopropyl adipate + tazarotene + citric acid + potassium citrate + water + hydrocarbon propellant
- Most distinctive ingredient driver: sorbic acid at about 6% (per your claim text)
- Most distinctive active driver: tazarotene about 5%
- Most distinctive preservative/pH system: citric acid about 0.1% + potassium citrate about 0.03%
Claim 2: potassium sorbate variant
- Most distinctive preservative switch:
- sorbic acid replaced with potassium sorbate at about 0.15%
- Otherwise similar base build:
- tazarotene about 5%
- citric acid about 0.1% + potassium citrate about 0.037%
- Propellant load remains the same: 7 to 8 g/100 g aerosol base
Claim 3: higher tazarotene + different oil load + different sorbic acid level
- Most distinctive oil phase difference: light mineral oil about 8% (vs about 6% in claims 1 and 2)
- Most distinctive preservative/acid balance: sorbic acid at about 8% (as your text reads “about 8% sorbic acid”) or if the ordering is interpreted differently, the claim still differs from claims 1 and 2
- Most distinctive active driver: tazarotene about 7%
Patent landscape: what to look for around US 8,808,716
1) Competitive pressure from tazarotene topical formulations
Tazarotene is a known active with multiple topical delivery formats across the market (creams, gels, foams, lotions). Patent landscapes for tazarotene are typically dense around:
- Formulation scaffolds (vehicle type, emulsifiers/surfactants)
- Particle/viscosity control (for gels/creams/foams)
- Preservative and acid/base systems (stability and microbiological control)
- Propellant and aerosol engineering (for foams and sprays)
US 8,808,716 fits squarely into that formulation band because it is an aerosol foam composition with a very specific base recipe.
2) The key landscape question: are other patents also claiming similar “oil-in-water aerosol foam” recipes?
For any competitor dossier, the relevant overlaps will be around:
- Aerosol foam formulations delivering tazarotene
- Oil-in-water emulsion vehicles using nonionic surfactants like Ceteareth-type materials
- Emollients/esters like diisopropyl adipate
- Preservative systems using sorbic acid or potassium sorbate plus citric acid/potassium citrate buffering
- Propellant quantification for foam performance and valve/aerosol behavior
The fact that US 8,808,716 hard-codes weight percentages for these components makes it likely that competing formulations carved out by different excipient choices or different propellant loads are handled in separate patent families. Those families can still pose risk if they converge on the same narrow composition targets.
3) Likely design-around vectors (based on the claim structure)
Because the claims lock in multiple ingredients at near-fixed percentages, design-around strategies usually must move at least one of these levers enough to avoid meeting each limitation:
- Change propellant type (claim requires “hydrocarbon propellant”) or change the loading outside 7 to 8 g/100 g
- Replace Ceteareth 12 with a different emulsifier system
- Change the oil phase composition (light mineral oil level or replace entirely)
- Change the preservative pairing (sorbic acid vs potassium sorbate, or change acid/citrate balance)
- Change tazarotene level enough to exit the “about 5%/about 7%” windows
- Change the antioxidant level (BHT about 0.1% is anchored in all claims)
These vectors are derived from the claim’s rigid listing style and the explicit propellant limitation.
Scope summary for business decisions
What the claims cover (commercially relevant formulation features)
A product that is:
- An aerosol foam with an oil-in-water emulsion
- Contains a base that matches one of the enumerated compositions (claims 1-3)
- Uses hydrocarbon propellant at 7 to 8 g per 100 g aerosol base
What the claims do not cover (based on claim language)
- Therapeutic methods (no dosing/regimen claim text provided here)
- Non-aerosol formats (no spray pump, gel tube, cream base, or non-pressurized foam claims are shown)
- Formulations that do not hit the enumerated “about” weight percent values for the listed excipients/active
- Aerosol bases with non-hydrocarbon propellants or outside the propellant mass window
Key Takeaways
- US 8,808,716 is a tightly constrained formulation patent: oil-in-water aerosol foam plus a fully enumerated aerosol base recipe and a specific hydrocarbon propellant mass window (7 to 8 g per 100 g aerosol base).
- Three claim variants cover different preservative and composition points: sorbic acid system (claim 1), potassium sorbate system (claim 2), and a different oil/active level variant (claim 3).
- Design-around risk is primarily driven by whether a competitor matches the “about” weight-percent targets for multiple components simultaneously, not by broad vehicle category labels.
- Landscape assessment should prioritize other tazarotene aerosol foam patents that claim different propellant loadings or different excipient recipes, because US 8,808,716’s precision can be avoided by moving at least one locked parameter.
FAQs
1) Is US 8,808,716 a method-of-treatment patent?
No. The provided claims are composition claims that define an aerosol foam formulation with a specific aerosol base and propellant loading.
2) What is the single most quantifiable non-base element in the claims?
The hydrocarbon propellant amount: about 7 to about 8 g per 100 g aerosol base.
3) Do the claims require sorbic acid specifically?
Not across all claims. Claim 1 uses sorbic acid, while claim 2 uses potassium sorbate. Claim 3 differs again.
4) What active ingredient level is claimed?
Tazarotene is about 5% in claims 1 and 2 and about 7% in claim 3 (as reflected in your claim text).
5) What vehicle type is required?
The claims require an oil-in-water emulsion aerosol foam composition with both an oil phase and a water phase.
References
[1] User-provided claim text for United States Drug Patent 8,808,716 (Claims 1-3).
