Details for Patent: 8,435,498

Summary for Patent: 8,435,498

Title:	Penetrating pharmaceutical foam
Abstract:	The invention relates to an alcohol-free cosmetic or pharmaceutical foam composition comprising water, a hydrophobic solvent, a surface-active agent, a gelling agent, an active component selected from the group of urea, hydroxy acid and a therapeutic enhancer and a propellant. The foam further comprises active agents and excipients with therapeutic properties having enhanced skin penetration.
Inventor(s):	Dov Tamarkin, Doron Friedman, Meir Eini
Assignee:	Vyne Therapeutics Inc
Application Number:	US12/752,718
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 8,435,498
Patent Claim Types: see list of patent claims	Use; Composition; Delivery;

Scope and Claims Review of US Patent 8,435,498 (Breakable Thermally Stable Foam from Foamable Emulsion for Skin/Mucosal Application)

US 8,435,498 claims methods where a mechanically “broken” thermally stable foam is applied to skin or mucosal surfaces. Patent scope is driven by (i) a specific emulsion-to-foam formulation architecture (surface-active agent + non-volatile hydrophobic solvent + gelling agent + defined “enhancer” component + water + liquefied/compressed gas propellant; alcohol cap at 7.5 wt%), and (ii) functional application mechanics (spreading or collapsing the breakable foam by mechanical force at a target site). The claims are broad on therapeutic indications and active-agent payloads, but narrower on formulation boundaries (component categories and compositional ranges).

H1: US Patent 8,435,498 Claims, Scope, and US Patent Landscape for Breakable Thermally Stable Foam Emulsion Therapeutics

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What is US Patent 8,435,498 claiming in plain scope terms?

Core independent claim theme (Claim 1):
A method for skin or mucosal application where a user spreads or collapses a breakable thermally stable foam at/near a target site. The foam is obtained by dispensing a foamable emulsion composition with these structural limits:

• Surface-active agent: about 0.1–5 wt%
• Liquid, non-volatile hydrophobic solvent: about 5–50 wt%
• Gelling agent: about 0.1–5 wt%
• Component selected from: urea, a hydroxy acid, a therapeutic enhancer, or mixtures
• Water
• Liquefied or compressed gas propellant
• Alcohol cap: total of methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol (or mixtures) is ≤ 7.5 wt%

Dependent claim claim-types:

• Foam physical-property constraints (specific gravity)
• Surfactant chemistry constraints (HLB range; non-ionic surfactants)
• Gelling agent chemistry (amphiphilic copolymer)
• “Component” compositional embodiments (urea ranges; hydroxy acid ranges; urea + hydroxy acid ranges; enhancer lists)
• Application-adjuvant/active-agent broad payload (foam adjuvant; therapeutic actives list)
• Formulation ratios (surface-active agent : hydrophobic solvent)
• Indication lists for skin and mucosa disorders

Claim duplication indicates two overlapping independent method templates:

• Claim 1 is generic to the formulation categories and compositional ranges.
• Claim 23 is a parallel method claim that includes a specific enumerated list of surface-active agents and reorganizes categories of the gelling agent/therapeutic enhancer/component selection.

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What are the independent claim elements and how do they constrain infringement?

Independent Claim 1 element map (the “hard constraints”)

In infringement analysis, Claim 1 requires all of the following elements:

1. Method step: spreading or collapsing a foam by mechanical force at/near a target site.
2. Foam must be:
   • Breakable
   • Thermally stable
3. Foam must be obtained by dispensing a foamable emulsion composition that has:
   • (i) surface-active agent 0.1–5 wt%
   • (ii) 5–50 wt% non-volatile hydrophobic solvent
   • (iii) gelling agent 0.1–5 wt%
   • (iv) a component selected from urea, a hydroxy acid, a therapeutic enhancer, or mixtures
   • (v) water
   • (vi) liquefied/compressed gas propellant
4. Composition must contain no more than 7.5 wt% total of specified lower alcohols.

Independent Claim 23 element map (the “hard constraints”)

Claim 23 adds a specific surfactant sub-list (polysorbates, polyoxyethylene fatty ether esters, sorbitan derivatives, sodium taurate/oleoyl taurate, SLS and TEA lauryl sulfate, sucrose esters, cocamidopropyl betaine, etc.). It also reconfigures the composition element categories as:

• Surface-active agent (enumerated list) 0.1–5 wt%
• Gelling agent 0.1–5 wt%
• A “therapeutic enhancer and a component” selected from urea, hydroxy acid, active agent, or combinations
• Water
• Propellant
• Alcohol cap ≤ 7.5 wt%

Key infringement leverage points

• Foam identity: both claims require “breakable” and “thermally stable” characteristics. Competitors attempting non-breakable foams or unstable foams reduce risk.
• Formulation architecture: competitors must match the emulsion-to-foam composition structure, including the alcohol cap and the non-volatile hydrophobic solvent percentage.
• Surfactant selection:
  • Claim 1 is not restricted to a particular surfactant chemistry beyond wt% and optional HLB/non-ionic dependent claims.
  • Claim 23 is restricted by the enumerated surfactant list, so surfactant substitution is a potential design-around if Claim 23 is asserted.
• Component scope (“urea / hydroxy acid / enhancer”): the claims cover common topical humectants/keratolytics/enhancers; design-around depends on eliminating all such components or shifting them outside claimed categories.

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What does the claim language mean by “breakable thermally stable foam” and “mechanical force”?

Breakable foam is claimed functionally: the foam must be spread/collapsed by mechanical force. A common risk for design-around is using foam that is not intended to collapse/spread under user mechanics (e.g., rigid gels, films, or non-collapsible foams).

Thermally stable suggests the foam maintains its structure under temperature conditions relevant to use or storage. Competitors using foams with known thermal collapse risk could be outside scope, but this is a factual/technical determination.

Mechanical force is a method limitation that likely covers standard dispensing and spreading actions (rubbing, pressing, troweling, applying applicator pressure). Claims are drafted broadly to cover manual spreading or collapsing.

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Which formulation ranges and ingredient caps define the protected emulsion-to-foam?

Fixed percentage bands (Claim 1)

• Surface-active agent: 0.1–5 wt%
• Non-volatile hydrophobic solvent: 5–50 wt%
• Gelling agent: 0.1–5 wt%
• Alcohols: ≤ 7.5 wt% total (methyl/ethyl/isopropyl/butyl alcohol)

These three percentage bands are the main numeric “gatekeepers.” A competitor that moves the surfactant below 0.1 wt% or above 5 wt% avoids the claim range, as long as the full combination elements are also absent.

Surfactant HLB and non-ionic limitations (dependent claims)

• HLB range 9–14 (Claim 3)
• Non-ionic surfactant (Claim 4)

These are dependent: they do not constrain Claim 1 unless those dependents are asserted. If litigating, they can increase claim coverage for formulations that match those parameters.

Gelling agent structure (dependent claim)

• Amphiphilic copolymer (Claim 5)

Foam specific gravity constraint (dependent claim)

• 0.01–0.1 g/mL (Claim 2)

This can be a technical test point for infringement/validity defenses, but again is dependent.

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How broad are the “component” embodiments (urea, hydroxy acids, enhancers)?

Urea embodiments

• Urea as the component at 1–50 wt% (Claim 6)
• Narrower embodiments:
  • 10–20 wt% (Claim 7)
  • 20–50 wt% (Claim 8)

This is wide enough to cover low and high urea formulations, including typical keratolytic/humectant concentrations.

Hydroxy acid embodiments

• Hydroxy acid component at 1–30 wt% (Claim 9)
• Narrower embodiment:
  • 1–10 wt% (Claim 10)

Urea + hydroxy acid combination

• 1–30 wt% urea plus 1–30 wt% hydroxy acid (Claim 11, as drafted: urea 1–50 and hydroxy acid 1–30, with internal ranges by wording)

Claim 11 indicates that the “component” category can be a mixture of urea and hydroxy acid within broad ranges.

Therapeutic enhancer list (Claim 12)

Claim 12 enumerates a large set of enhancers/humectants/moisture retaining agents, including:

• Propylene glycol, butylene glycols
• Glycerol, pentaerythritol, sorbitol, mannitol
• Oligosaccharides
• Dimethyl isosorbide
• Monooleate of ethoxylated glycerides (8–10 EO units)
• PEG 200–600
• Transcutol
• Glycofurol
• PEG ethers
• Cyclodextrin

This list overlaps substantially with common topical penetration enhancer and humectant ingredient classes. Claim 13 also broadly covers “at least one humectant or moisture-retaining agent.”

Therapeutic enhancer vs component overlap

Claim 1 treats “component” as selected among urea, hydroxy acid, therapeutic enhancer. Claim 12 further defines therapeutic enhancers by list. Claim 23 expands the “therapeutic enhancer and a component” concept with urea/hydroxy acid/active agent combinations.

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What active-agent and indication coverage exists across the dependent claims?

Active agent payload breadth (Claim 16)

Claim 16 contains an extensive list of active agents, including:

• Antibacterial, antifungal, antiviral
• Anti-inflammatory, steroids, corticosteroids
• Antihistamine, NSAIDs
• Immunomodulating, immunosuppressant
• Anti-allergic
• Local anesthetic
• Keratolytics, retinoids
• Insecticide/repellent
• Anti-cancer, photodynamic therapy agents
• Agents for burns, wounds, cuts, ulcers
• Anti-acne, anti-wrinkle, anti-atrophy
• Antioxidants/radical scavengers
• Self-tanning, skin lightening/whitening
• Hair growth disorder agents
• Humectant/moisture-retaining agent, hydroxy acid
• Cellulite treatment agents

This is a strong indication of the claim strategy: protect a delivery system/method that can carry many therapeutic actives.

Indication lists for skin/mucosal disorders (Claims 20–22 and 21)

The claims list disorders spanning:

• Pain, wounds, burns, cuts, ulcers
• Ear channel disorders
• Vaginal, rectal, penile, urethra disorders
• Dermatologic diseases including dermatitis subtypes, psoriasis, infections (bacterial/fungal/parasites/scabies/pediculosis), vitiligo, hyperpigmentation, ichthyosis, actinic keratosis
• Bullous diseases, sunburn/photosensitivity and melanoma reactions to sunlight
• Pressure sores
• Disorders of sweating
• Non-dermatological disorders responsive to topical/transdermal delivery
• Localized pain, joint pain, osteoarthritis, pelvic pain
• Hormone-responsive conditions
• Vulvovaginal infections and specific pathogens
• Herpes simplex, genital ulcers, genital warts, STDs
• Sexual dysfunction disorders responsive to topical therapy
• Anal fistula, hemorrhoids, anal fissures

Claim 22 is broad in “disorder known to be responsive to the at least one active agent,” which further reduces the ability to narrow infringement based on indication.

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What do the dependent physical/ratio claims add for claim construction?

Surfactant-to-solvent ratio limits (Claims 17–18)

• 1:8 to 1:16 (Claim 17)
• 1:16 to 1:32 (Claim 18)

These depend on numeric definitions of “surface active agent” and “hydrophobic solvent.” They may become technical issues in claim comparison and validity.

Oil-in-water emulsion (Claim 19)

• “Emulsion is an oil in water emulsion.”

If a competitor uses a different emulsion type (e.g., water-in-oil), that design choice targets this dependent limitation.

Foam adjuvant (Claim 14)

Adds allowance for other foam-formulation adjuvants without changing the core claimed architecture.

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How does Claim 23 differ from Claim 1 in ways that matter in design-around?

Claim 23 surfactant enumeration is the primary difference.

• If a competitor uses a surfactant outside the enumerated list, Claim 23 coverage can be weakened while Claim 1 may remain available if other claim elements are met.
• Claim 1 only requires surfactant wt% (and optionally HLB/non-ionic in dependents), so Claim 23 can narrow coverage only if a plaintiff relies on the specific surfactant list.

Claim 23 also reorganizes “component” and “therapeutic enhancer” into a combined construct that includes active agent as a possible selection in the “component selected from” group.

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What is the likely claim strategy: device- or formulation-driven?

US 8,435,498 reads like a delivery system patent with broad therapeutic payload coverage:

• It claims a mechanically breakable, thermally stable foam.
• It claims the dispensed emulsion composition that yields the foam.
• It allows a wide list of actives and indications.
• It limits specific formulation ranges and alcohol cap.

That structure often positions the patent for enforcement against topical foam products and against formulation changes that preserve the same foam-making composition architecture.

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US patent landscape for this foam/emulsion/penetration-enhancer category: where overlap risk is highest?

The scope provided contains only the claims, not the patent’s full bibliographic record, prosecution history, citations, or family data. Without those, a complete, numbered landscape mapping (other US patents by number, assignees, filing dates, priority claims, and litigation status) cannot be produced accurately from the information given.

What can be concluded from the claim text itself about likely overlap zones in the US:

• Foamable emulsions with gas propellant for topical/mucosal use are a recurring design space.
• Non-volatile hydrophobic solvents plus low-level surfactant and gelling agents to stabilize foam are common formulation principles.
• Urea and hydroxy acids plus penetration enhancers/humectants are standard components in topical keratolytics and treatment enhancers.
• Oil-in-water emulsions and surfactant HLB targets appear frequently in formulation IP.
• Thermally stable foam and mechanically breakable/collapsible foam are more specific characteristics, and could be the differentiating feature most competitors would need to match to infringe.

Because the claim text is broad on actives/indications, overlap with many therapeutic-topic patents is possible. The strongest novelty and litigation value typically lies in the foam generation method + compositional architecture + alcohol cap + mechanical breakability.

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Key design-around handles a competitor would analyze against US 8,435,498

1. Alcohol cap: keep alcohols (methyl/ethyl/isopropyl/butyl) below or eliminate them, but note the claim allows up to 7.5 wt%. A competitor would test compliance with the cap for total alcohol content.
2. Surfactant wt% and HLB/non-ionic choices: moving surfactant outside 0.1–5 wt% avoids Claim 1’s surfactant band.
3. Non-volatile hydrophobic solvent band: moving hydrophobic solvent outside 5–50 wt% avoids the numeric element.
4. Gelling agent band: moving gelling agent outside 0.1–5 wt% avoids the numeric element.
5. Component category elimination: avoid including urea, hydroxy acids, and therapeutic enhancer categories as claimed. Because “therapeutic enhancer” includes a long list, this is non-trivial.
6. Foam mechanics and stability: shift away from “breakable thermally stable foam” to foam types that do not collapse/spread in the claimed manner or are thermally unstable.
7. Surfactant list in Claim 23: if relying on Claim 23, select surfactants outside the enumerated list. This does not avoid Claim 1 unless it also breaks other elements.

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When does exclusivity end and when can generics enter for this type of method patent?

This depends on the specific FDA product, marketing exclusivity, and the patent’s expiration and any granted terminal disclaimers. The user-provided input does not include:

• the patent expiration date,
• the drug product tied to the formulation,
• Orange Book listings,
• FDA approval dates,
• or any Paragraph IV litigation or settlements.

No complete and accurate timeline can be generated from the provided information alone.

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Key Takeaways

• US 8,435,498 claims a method of topical or mucosal application using a mechanically breakable, thermally stable foam.
• Infringement hinges on the foam being dispensed from a foamable emulsion with three specific numeric ranges (surfactant 0.1–5 wt%, non-volatile hydrophobic solvent 5–50 wt%, gelling agent 0.1–5 wt%) and a strict alcohol cap of 7.5 wt% for specified alcohols.
• The formulation’s “component” coverage is expansive: urea, hydroxy acids, and a broad enumerated enhancer/humectant list, enabling many topical therapeutic combinations.
• Therapeutic scope is very broad across active agent classes and dermatologic and mucosal indications, suggesting enforcement focus is the delivery system rather than the medical indication.
• Claim 23 adds a surfaced-active agent enumeration that can create a narrower design-around path compared with Claim 1, but Claim 1’s broader surfactant requirement still leaves significant coverage potential.

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FAQs

1. How can a reformulation avoid infringement of US 8,435,498 if it still uses urea or hydroxy acids?
   By shifting other hard elements (surfactant wt%, hydrophobic solvent wt%, gelling agent wt%, alcohol cap, or foam breakability/thermal stability).

2. Does US 8,435,498 require a specific foam application device or can manual spreading count as “mechanical force”?
   The claims do not specify an applicator type; they require spreading/collapsing by mechanical force at the target site.

3. If a product uses a non-ionic surfactant with HLB outside 9–14, is it still potentially covered?
   HLB and non-ionic status are dependent limitations; coverage under independent Claim 1 does not require those features unless a dependent claim is asserted.

4. What is the biggest vulnerability in Claim 23 for a competitor?
   The surfactant must be within the enumerated list; using a surfactant outside that list can reduce Claim 23 relevance.

5. Can the patent cover mucosal delivery systems that resemble the foam but do not use propellant gas?
   Both independent claims require a liquefied or compressed gas propellant as part of the foamable emulsion composition.

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References

No references are included because the prompt does not provide bibliographic records, prosecution data, FDA product linkage, or citation sources required to produce a complete, accurate US patent landscape tied to US 8,435,498.

Drugs Protected by US Patent 8,435,498

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate

Foreign Priority and PCT Information for Patent: 8,435,498

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Israel	152486	Oct 25, 2002

International Family Members for US Patent 8,435,498

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2003279493
Australia	2004261063
Australia	2004266502
Australia	2004313285
Australia	2004321183