US Patent 9,415,029: Scope, Claims, and US Landscape for Sequenced Topical Diclofenac on the Knee

United States Patent 9,415,029 claims a method of applying a topical diclofenac formulation to a patient’s knee with osteoarthritis pain, then applying a second prescription topical medication or other specified topical agent after the diclofenac dries, during an ongoing course of diclofenac treatment, with an express limitation that the first application does not enhance systemic absorption of the subsequently applied topical agent.

The claim core is not “topical diclofenac for knee osteoarthritis.” It is the sequencing rule plus a high-DMSO, hydroalcoholic, gelling vehicle profile for diclofenac, tied to systemic exposure non-enhancement for the second topical.

What do the independent claim elements cover? (Claim 1 as the anchor)

Claim 1 is a three-part method that can be read as: (A) apply diclofenac with a tightly defined composition and viscosity, (B) wait for it to dry, (C) then apply a different topical prescription medication to the same area, during ongoing diclofenac treatment, while ensuring the first does not enhance systemic absorption of the second.

A. First medication: topical diclofenac formulation on the knee

Indication / anatomical site: “to treat osteoarthritis of the knee”
Topical active: diclofenac sodium 2% w/w
Vehicle composition (to 100% w/w):
- Dimethyl sulfoxide (DMSO): about 40% to about 50% w/w
- Ethanol: about 23% to about 29% w/w
- Propylene glycol: about 10% to about 12% w/w
- Hydroxypropylcellulose: about 2.5% w/w
- Water: remainder to 100%
Viscosity limitation: 500 to 5000 centipoise

B. Dry-time sequencing

“waiting for the treated area to dry”

This is a functional requirement that creates the timing window. The claim does not quantify minutes, but it does require completion of the drying step before the second application.

C. Second medication: different topical prescription after drying

“subsequently applying a second prescription medication consisting of a topical medication other than said first medication”
“after said treated area is dry”
“wherein said subsequent application occurs during a course of treatment of said patient with said topical diclofenac preparation.”

D. Systemic absorption guardrail

“wherein said step of applying a first medication does not enhance the systemic absorption of the subsequently applied” second medication.

Claim 3 repeats this guardrail explicitly as a separate limitation: no enhancement of systemic absorption of the subsequently applied topical agent.

Claim 4 combines Claim 1’s full structure with the explicit systemic absorption limitation in the same claim.

How do dependent claims narrow the diclofenac vehicle and the second agent?

DMSO narrowing

Claim 2: diclofenac formulation has about 45.5% w/w DMSO (inside the 40-50% band)
Claim 5 and Claim 7: also set about 45.5% w/w DMSO for their narrower claim contexts.

This is important because the DMSO range is broad enough to support formulation design-around within the literal perimeter. Claim 2/5/7 pin one value, but those are dependent, so they only apply when that dependent claim is asserted.

Systemic absorption non-enhancement (explicit)

Claim 3: method does not enhance systemic absorption of the subsequently applied topical medication.
Claim 4: duplicates the explicit non-enhancement requirement in the claim’s full set of limitations.

Second agent examples: sunscreen and insect repellant

Claim 6: after drying, apply a sunscreen or an insect repellant (and the non-enhancement constraint is expressly applied to “sunscreen, or insect repellant”).
Claim 8: sunscreen option.
- Claim 9: sunscreen comprises oxybenzone (in practice, oxybenzone is benzophenone-3).
Claim 10: insect repellant option.
- Claim 11: insect repellant comprises DEET (N,N-diethyl-m-m-toluamide; claim text reads N,N-diethyl-m-toluamide (DEET)).
- Claim 12: insect repellant comprises 2,4 D dimethylamine salt (2,4 D).

These dependent claims define concrete candidate second agents that could collide with the “second topical agent after diclofenac dries” method.

What is the practical claim scope for a competitor applying other topicals over diclofenac?

Literal coverage requires all key constraints to be met

A method infringes Claim 1 if it satisfies all of the following in one method:

Applies a diclofenac topical to the knee for knee osteoarthritis pain
The diclofenac composition meets the 2% diclofenac sodium plus vehicle and viscosity 500-5000 cP
The method waits for the treated area to dry
Then applies a different prescription topical medication to the same area
The second application occurs during the course of diclofenac treatment
The first application does not enhance systemic absorption of the second topical agent

Design implications

If a competitor applies a different topical before drying, they avoid the “after drying” sequence requirement for Claim 1 and its dependents.
If the diclofenac vehicle misses the DMSO/ethanol/propylene glycol/hydroxypropylcellulose profile or the viscosity band, they avoid the literal composition/viscosity limitations.
If systemic absorption is enhanced (or the method cannot meet the “does not enhance systemic absorption” limitation), the competitor avoids literal coverage, even if everything else matches.
If the second topical is not a prescription medication, Claim 1 is less directly implicated; Claim 6 expands into sunscreen/insect repellant, but it still frames the method as “second prescription medication” in Claim 1 and later claims specify sunscreen/insect repellant within their own dependent claim text.

Claim charting: coverage map by element

Claim element	What must be true	Scope impact
Patient and site	Knee of a patient with pain due to osteoarthritis	Limits to knee osteoarthritis use
First agent	Topical diclofenac preparation with 2% w/w diclofenac sodium	Locks active dose
Vehicle	DMSO 40-50%, ethanol 23-29%, propylene glycol 10-12%, HPC 2.5%, water to 100%	Tight vehicle definition; still ranges
Viscosity	500-5000 cP	Adds physical parameter that can be tested/argued
Timing	Wait for treated area to dry	Sequence gate for infringement
Second agent	“Topical medication other than first”; prescription in Claim 1	Gate on regulatory status of second agent
Continuity	Second application occurs during course of diclofenac treatment	Restricts “single crossover” scenarios
Systemic absorption	First application does not enhance systemic absorption of second	Explicit pharmacokinetic constraint

What is the patent landscape likely to look like around this concept in the US?

Because the user-provided text includes only the claims of 9,415,029 and not:

the assignee,
prosecution history,
priority/application numbers,
related patents/citations,
or the specification’s embodiments and testing methods,

a complete landscape cannot be built with verified bibliographic certainty for individual competitor patents. Under those constraints, the only defensible landscape is conceptual positioning: where 9,415,029 sits relative to typical topical NSAID patents and where it likely blocks specific formulation+sequencing combinations.

Landscape anchor: “diclofenac gel” vs. “DMSO/ethanol topical delivery vehicles”

US topical NSAID patents often claim:

the active,
a topical carrier base (gels/creams/patches),
or device-based delivery.

9,415,029 is closer to a subgroup that uses:

high DMSO as an enhancer/permeation component,
ethanol/propylene glycol as co-solvents,
and a cellulose-based gelling agent (hydroxypropylcellulose),
with a measured viscosity.

This matters because competitors frequently try to use DMSO-like penetration promoters and must address systemic absorption and drug-drug interactions for co-applied topicals.

The differentiator: sequencing after drying + systemic non-enhancement

Many topical patents do not claim:

a drying step before a second topical is applied, or
a non-enhancement of systemic absorption of the subsequently applied topical.

9,415,029’s claim set is built to capture a very specific real-world use case: multiple topical products applied to the same area over the course of diclofenac treatment.

Potential collision points for competitors

Competitors trying to market:

diclofenac formulations with similar DMSO/high-solvent carriers and viscosities,
and instructions that allow co-application with other products

face exposure if the method is implemented in the claimed sequence and the systemic non-enhancement condition is met.

Conversely, competitors may seek to avoid by:

changing composition outside the ranges,
adjusting viscosity,
requiring longer/shorter drying time and applying second products before full dryness,
or by designing formulations such that systemic absorption is enhanced (which may change safety and labeling, but it is the opposite of the patent’s limitation).

Scope by claim families inside 9,415,029: what is the “second agent” coverage?

Second topical prescription medication (broad)

Claim 1: second agent is “a second prescription medication… topical medication other than said first medication”
The second agent is not limited in type beyond being topical and prescription.

Second agent is sunscreen or insect repellant (specific)

Claim 6: sunscreen or insect repellant
Claim 9: sunscreen comprises oxybenzone
Claim 11: insect repellant comprises DEET
Claim 12: insect repellant comprises 2,4 D dimethylamine salt (2,4 D)

The inclusion of oxybenzone and DEET suggests the patent was drafted around commonly co-applied consumer/OTC-type topical products; the claim language anchors them into the method with the systemic absorption non-enhancement constraint.

Enforceability posture for the method claims

Method claims are typically enforced against:

prescribers,
pharmacists,
and in some situations, product instructions used by end users (depending on jurisdiction and proof standards for induced/contributory acts).

The strongest “enforcement lever” is the tightness of:

composition and viscosity,
drying step,
and systemic absorption non-enhancement limitation.

These are elements that can be attacked by formulation testing and pharmacokinetic evidence.

Key Takeaways

US 9,415,029 is a sequencing method patent, not a basic diclofenac topical patent: it requires applying a specific high-DMSO diclofenac formulation to the knee, waiting for drying, then applying a different topical prescription medication during diclofenac treatment.
The diclofenac composition is tightly constrained: 2% w/w diclofenac sodium, 40-50% DMSO, 23-29% ethanol, 10-12% propylene glycol, 2.5% hydroxypropylcellulose, plus water, with viscosity 500-5000 cP.
The claim includes a pharmacology limitation: applying diclofenac does not enhance systemic absorption of the subsequently applied topical agent.
Dependent claims carve out common co-applied agents: sunscreen with oxybenzone and insect repellents with DEET or 2,4 D dimethylamine salt.

FAQs

1) Does 9,415,029 cover applying sunscreen or DEET before the diclofenac dries?

No. The method requires the treated area to dry before the second topical is applied.

2) If a competitor matches the diclofenac active but changes the vehicle, do they fall outside the claim?

Yes, if they miss the claimed composition bands (DMSO/ethanol/propylene glycol/HPC/water) or the 500-5000 cP viscosity requirement.

3) Is the second medication limited to prescription products?

Claim 1 frames it as a second prescription medication. Dependent claim 6 focuses on sunscreen or insect repellant, but still within the claim’s overall sequencing and systemic non-enhancement structure.

4) What is the single most limiting step for enforcement in practice?

The combination of (i) exact composition/viscosity of the diclofenac preparation, and (ii) the “wait until dry” sequencing.

5) Why is “does not enhance systemic absorption” a major scope limiter?

It adds a pharmacokinetic constraint that can distinguish between formulations that do or do not increase systemic exposure of co-applied topicals, shaping both claim coverage and litigation evidence.

References

[1] United States Patent 9,415,029. Claims as provided in the user prompt.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Horizon	PENNSAID	diclofenac sodium	SOLUTION;TOPICAL	204623-001	Jan 16, 2014		DISCN	Yes	No	9,415,029	⤷ Start Trial				USE OF TOPICAL DICLOFENAC SODIUM FOR TREATING PAIN	⤷ 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

Details for Patent: 9,415,029

Which drugs does patent 9,415,029 protect, and when does it expire?

Summary for Patent: 9,415,029