Scope, Claims, and U.S. Patent Landscape for US Patent 8,807,861
US Patent 8,807,861 claims a transdermal delivery system that dispenses a liquid formulation from a container through a detachable dispensing/applicator support into a reservoir in contact with skin, then spreads the liquid using a deformable reservoir wall with a base that blocks liquid flow through the base. The claims also tightly cabin formulation variables (penetration enhancer classes, specific enhancer exemplars, and volatile solvent ranges) and constrain use to an application method that includes spreading over at least an axilla.
What is the invention’s core claim architecture?
Claim 1 is the backbone. It defines a combined system with these elements and functional relationships:
System elements (Claim 1)
- Container holding a liquid composition containing a physiologically active agent.
- Dispensing device that delivers the liquid composition from the container.
- Applicator for applying the liquid to skin for transdermal administration.
- Detachability mechanic: the applicator includes a support detachably contactable to the dispensing device or container, and the support detaches to permit dispensing.
- Reservoir mounted on the support:
- defines a reservoir space
- receives a volume of the liquid composition from the container/dispensing device
- Reservoir structure:
- has a base
- has a resiliently deformable wall that is “substantially transverse” to the base
- wall has a working surface used to spread liquid on skin
- base has a surface such that the liquid composition cannot pass through the base
- Functional outcome: deform the wall against skin so the working surface spreads the liquid on the skin area for transdermal delivery.
Key structural-functional limit
The combination of (i) a deformable wall used as the spreading surface and (ii) a base that is liquid-impervious (“cannot pass through”) drives the separation between:
- spreading over the skin surface (by wall working surface under deformation), and
- preventing liquid loss through the base.
This is the primary structural hook for infringement-by-structure and design-around resistance.
How broad is Claim 1 across product form, drug class, and device form factor?
Physiologically active agent scope
Claim 1 is broad on agent identity: it requires only “a physiologically active agent.” Claims 7-8 then narrow to hormones and specifically androgens.
Claim 7 (narrower): active agent is at least one hormone selected from:
- oestrogens
- progestagens
- androgens
Claim 8 (narrower): androgen selected from:
- testosterone and derivatives thereof
So, Claim 1 covers any agent, while dependent claims cover hormone/androgen use cases.
Applicator and reservoir scope
Claim 1 is broad on shape except for the reservoir micro-structure:
- deformable wall transverse to base
- base blocks liquid passage through it
- working surface spreads liquid
Dependent claims add specific geometries (skirt, double-wall, integrally formed flexible membrane).
Operational limitation: axilla application
The method in Claim 9 explicitly requires spreading over at least one axilla. That is a usage limitation specific to Claim 9’s method scope (not necessarily Claim 1’s device scope, unless a court reads “applying to an area of skin” in Claim 1 as requiring axillary application, which is not stated).
What do the dependent claims add to formulation scope?
Penetration enhancer inclusion (Claim 2)
Claim 2 adds that the composition includes a penetration enhancer.
Penetration enhancer class list (Claim 3)
Claim 3 lists specific enhancer categories:
- fatty acids
- fatty acid esters
- fatty alcohols
- glycols
- glycol esters
- 1,3-dioxolanes
- 1,3-dioxanes
- macrocyclic ketones containing at least 12 carbon atoms
- oxazolidinones and oxazolidinone derivatives
- alkyl-2-(N,N-disubstituted amino)-alkanoate esters
- (N,N-disubstituted amino)-alkanol alkanoates
- sunscreen esters
- mixtures thereof
This is a fairly expansive chemical taxonomy. It is not limited to a single chemical family.
Specific exemplar penetration enhancers (Claim 4)
Claim 4 narrows to one or a mixture of:
- octyl dimethyl-para-aminobenzoate
- octyl para-methyoxycinnamate
- octyl salicylate
Penetration enhancer concentration range (Claim 5)
Claim 5 constrains the penetration enhancer content to:
- 1 to 15% by weight of total composition.
Volatile solvent concentration and selection (Claim 6)
Claim 6 constrains the formulation to include:
- 40-90% by weight volatile solvent, selected from:
- ethanol
- ethyl acetate
- isopropanol
- acetone
- ethyl formate
- methyl acetate
- methyl ethyl ketone
- pentane
- chloroform
- dimethyl ether
- R134a
- mixtures thereof
Together, Claims 5-6 define a high-solvent, volatile-carrying composition strategy.
What do the dependent claims add to device structure and manufacturability?
Claims 10-20 add further structural constraints to Claim 1.
Reservoir geometry and integration
- Claim 10: reservoir has an open top configured to receive liquid from the dispensing device through the open top.
- Claim 11: support is relatively rigid compared to the wall so the wall is movable relative to support when spreading.
Skirt and double-wall structure (Claims 12-18)
- Claim 12: wall includes an outer skirt portion; lower edge of skirt attached to support.
- Claim 13: wall includes an inner portion from base to upper end.
- Claim 14: working surface extends over inner portion and outer skirt.
- Claim 15: inner and outer portions form a double-walled structure.
- Claim 16: base and wall formed integrally from a flexible membrane.
- Claim 17: inner portion substantially parallel to outer skirt portion.
- Claim 18: working surface extends over inner portion and outer skirt (a second recitation of working surface coverage).
Alternative membrane integration (Claims 19-20)
- Claim 19: base and wall formed integrally from flexible membrane.
- Claim 20: working surface extends over inner and outer skirt (reinforces Claim 14/18 but in the alternative dependency chain).
How the structural chain impacts competitive design
The strictness increases as you move from Claim 1 to Claims 12-20:
- Claim 1 only requires a resiliently deformable wall and a base blocking liquid passage.
- Claims 12-18 impose specific wall segmentation (inner/outer skirt), double-wall formation, and flexible membrane integration.
- Claims 16 and 19 add manufacturability constraints: integrally formed base and wall from flexible membrane.
A competitor that matches Claim 1’s functional elements but avoids skirt/double-wall or integral membrane construction may reduce exposure to dependent-claim infringement, while still potentially implicating Claim 1 if the base-blocking and deformable wall spreading functions are replicated.
What is the method scope and where is it territorially narrowed?
Claim 9 adds a method with three steps:
- Provide a system according to Claim 1.
- Apply the liquid composition including physiologically active agent to the reservoir space.
- Deform the wall and spread the liquid composition over the area of the skin surface “in at least one axilla.”
This does two things:
- It ties the reservoir-spreading mechanism to an anatomical site.
- It creates a method claim that is difficult to design around if the commercial use is axillary.
Claim map snapshot: what each claim covers
| Claim |
Scope type |
Key limitations |
| 1 |
Device system |
Container + dispensing + applicator with detachability; reservoir on support; base blocks liquid through; resilient deformable wall transverse to base; working surface spreads liquid |
| 2 |
Composition |
Includes penetration enhancer |
| 3 |
Composition |
Penetration enhancer from broad chemical classes (listed) + mixtures |
| 4 |
Composition |
Specific enhancer exemplars (octyl dimethyl PABA, octyl methoxycinnamate, octyl salicylate) alone or mixture |
| 5 |
Composition |
Penetration enhancer 1-15 wt% |
| 6 |
Composition |
Volatile solvent 40-90 wt%, selected list including ethanol/acetone/isopropanol/etc. and R134a |
| 7 |
Agent identity |
Active agent is hormone (oestrogen/progestagen/androgen) |
| 8 |
Agent identity |
Active agent is androgen (testosterone and derivatives) |
| 9 |
Method |
Spread on skin including at least one axilla; deform wall against skin |
| 10 |
Device geometry |
Open top reservoir receiving liquid through open top |
| 11 |
Device mechanics |
Rigid support relative to deformable wall |
| 12 |
Device structure |
Outer skirt on wall, skirt attached to support |
| 13 |
Device structure |
Inner portion from base to upper end |
| 14 |
Device structure |
Working surface spans inner + outer skirt |
| 15 |
Device structure |
Inner and outer portions form double-walled structure |
| 16 |
Manufacturing |
Base and wall integrally from flexible membrane |
| 17 |
Device structure |
Inner portion substantially parallel to outer skirt |
| 18 |
Device structure |
Working surface spans inner + outer skirt (reinforces) |
| 19 |
Manufacturing |
Alternative recitation: base and wall integrally from flexible membrane |
| 20 |
Device structure |
Working surface spans inner + outer skirt in the alternate chain |
What does the independent claim imply for infringement risk across product variations?
The infringement center of gravity is Claim 1.
A transdermal liquid delivery product could still fall within Claim 1 if it has:
- a reservoir that collects liquid after dispensing,
- a resiliently deformable wall that spreads liquid onto skin,
- a base that prevents liquid passage through it,
- and a detachability structure that allows the applicator support to detach to permit delivery.
Potential “design-around” axes present in the claim text
- Base permeability: the base must prevent liquid passage through it. If a competitor’s base allows permeation/flow through the base (as a structural feature), they may fall outside this specific limit.
- Spreading mechanism: Claim 1 uses deformation-driven spreading via a working surface. Products that spread liquid without a resiliently deformable transverse wall (for example, rigid metering or capillary spreading) reduce fit.
- Reservoir geometry: Claim 1 is less specific than Claims 12-20, but a reservoir space mounted on support is required.
- Detachability requirement: Claim 1 includes a support detachably contactable to dispensing device or container and detaches to permit dispensing. Fully integrated non-detaching cartridges may reduce fit with this element depending on how “detachably contactable” is construed.
How does this claim set position the patent landscape?
Based on the claim set alone, the patent is positioned at the intersection of:
- transdermal liquid-on-skin delivery
- mechanical spreading via deformable reservoir interfaces
- high volatile solvent formulations
- penetration enhancer selection and dosage ranges
- hormone/androgen application use cases
- axillary spreading method claims
Practically, this creates overlapping enforcement vectors:
- Device/applicator competition: companies with similar reservoir and deformable spreading interfaces face higher risk on Claim 1.
- Formulation competition: companies matching high volatile solvent and specific enhancer classes may face dependent-claim exposure, particularly if their active agent falls into hormone/androgen categories and the application site matches axilla (Claim 9).
- Combined product competition: a commercial product that is both structurally similar and formulation-aligned with Claims 2-6 is at the highest risk concentration.
What is the effective coverage boundary of the claim set?
Coverage boundary 1: device-core
- Broadest: Claim 1 covers any physiologically active agent.
- It is constrained by device mechanics and structure (reservoir + deformable transverse wall + base blocking liquid passage through base).
Coverage boundary 2: formulation overlays
Claims 2-6 add layered formulation constraints that narrow coverage when a product diverges in penetration enhancer choice/concentration or volatile solvent composition/range.
Coverage boundary 3: biological target and use method
Claims 7-9 narrow further:
- hormone/androgen scope (7-8)
- axilla spreading method (9)
A product that is structurally similar but intended for a different anatomy or uses non-qualifying enhancer/solvent ranges is less likely to land within the narrower dependent claims, while still risking exposure to Claim 1’s device-level coverage.
Key Takeaways
- Claim 1 controls the landscape: it requires a detachable support/applicator, a reservoir that receives liquid, a resiliently deformable wall with a working surface that spreads liquid on skin, and a base that the liquid cannot pass through.
- Claims 2-6 define formulation layers: penetration enhancers from a listed chemical taxonomy, specific enhancer exemplars, a 1-15 wt% enhancer window, and 40-90 wt% volatile solvent from a defined list.
- Claims 7-8 and 9 add target and use-site constraints: hormones/androgens and a method that spreads over at least one axilla.
- Claims 10-20 add structural detail: open-top reservoir, rigid support relative to the movable wall, skirt/double-wall geometry, and integrally formed flexible membrane construction.
- Design-around is clearest on the mechanical-spreading and base-blocking elements; formulation and axilla use are secondary narrowing filters unless the competitor aligns to them.
FAQs
-
Does Claim 1 require an axilla-specific application?
No. Axilla limitation appears in the method claim (Claim 9), not in Claim 1’s system claim language.
-
What is the single most explicit device limitation in Claim 1?
The base has a surface such that the liquid composition cannot pass through the base.
-
Can the patent cover transdermal delivery of any drug?
Claim 1 is agnostic to the physiologically active agent, but dependent claims narrow to hormones and specifically androgens.
-
Are the penetration enhancers limited to a single compound?
No. Claim 3 lists multiple classes; Claim 4 gives specific exemplar mixtures.
-
What formulation ranges are expressly claimed?
Penetration enhancer is 1-15 wt% (Claim 5) and volatile solvent is 40-90 wt% selected from a defined list (Claim 6).
References
[1] United States Patent 8,807,861.
