Details for Patent: 9,180,095

« Back to Dashboard

Which drugs does patent 9,180,095 protect, and when does it expire?

Patent 9,180,095 protects ZORVOLEX and is included in one NDA.

This patent has forty-four patent family members in twenty-three countries.

Summary for Patent: 9,180,095

Title:	Formulation of diclofenac
Abstract:	The present invention relates to methods for producing particles of diclofenac using dry milling processes as well as compositions comprising diclofenac, medicaments produced using diclofenac in particulate form and/or compositions, and to methods of treatment of an animal, including man, using a therapeutically effective amount of diclofenac administered by way of said medicaments.
Inventor(s):	Aaron Dodd, Felix Meiser, Marck Norret, Adrian Russell, H William Bosch
Assignee:	Iceutica Pty Ltd
Application Number:	US14/621,919
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 9,180,095
Patent Claim Types: see list of patent claims	Use; Composition; Formulation;

United States Patent 9,180,095: Diclofenac Acid Nanoparticle Claims, Scope, Expiration, and Patent Landscape

U.S. Patent No. 9,180,095 protects specified methods of treating pain with 18 mg or 35 mg solid oral doses of diclofenac acid having a submicron particle-size distribution and defined dissolution performance. The patent is directed to the product characteristics of Zorvolex, the diclofenac acid capsule marketed by Itero Biopharmaceuticals and associated with Iroko Pharmaceuticals’ proprietary nanoparticle technology. Its principal commercial value is the combination of dose strength, particle size, dissolution profile, and therapeutic use rather than diclofenac as an active ingredient generally.[1][2]

The patent has a projected statutory expiration date in April 2032, subject to any applicable patent-term adjustment or other record-specific modification.[1] Generic diclofenac sodium, diclofenac potassium, topical diclofenac, and conventional diclofenac products generally fall outside the claims because they do not necessarily contain diclofenac acid in the claimed particle-size range or satisfy the specified dissolution test.

What does U.S. Patent 9,180,095 protect?

Patent 9,180,095 protects methods of treating pain by administering a solid oral unit dose containing either 18 mg or 35 mg of diclofenac acid. The claimed diclofenac acid must meet two technical limitations:

1. A median particle size, measured on a volume-average basis, greater than 25 nm and less than 5,000 nm.
2. A specified percentage of diclofenac acid released within a defined time under a particular in vitro dissolution protocol.

The independent claims are claims 1 and 16.

Claim	Dose	Particle-size range	Dissolution requirement	Therapeutic use
1	18 mg	>25 nm and <5,000 nm	94% released by 75 minutes	Treating pain
16	35 mg	>25 nm and <5,000 nm	95% released by 75 minutes	Treating pain

The dissolution test requires USP Apparatus I, or the basket method, at 100 rpm and 37°C in 900 mL of 0.05% sodium lauryl sulfate in citric acid buffer at pH 5.75. These test conditions are material claim limitations. A formulation that releases the required percentage under a different medium, apparatus, pH, volume, or agitation speed does not necessarily satisfy the literal dissolution limitation.

How do the dependent claims narrow the patent scope?

Claims 2 through 15 narrow the 18 mg method. Claims 17 through 30 narrow the 35 mg method. The dependent claims create multiple overlapping claim positions based on particle size, dissolution speed, pain category, dosing frequency, and clinical effect.

Particle-size limitations

The dependent claims progressively reduce the maximum median particle size:

• Less than 3,000 nm
• Less than 2,000 nm
• Less than 1,900 nm
• Less than 1,700 nm
• Less than 1,500 nm

The lower boundary remains greater than 25 nm. These limitations are nested. A product with a median particle size of 1,200 nm could satisfy the less-than-5,000 nm, less-than-3,000 nm, less-than-2,000 nm, less-than-1,900 nm, less-than-1,700 nm, and less-than-1,500 nm limitations, assuming all other claim elements are met.

Dissolution limitations

The patent claims progressively faster release:

• 94% release by 60 minutes
• 94% release by 45 minutes
• 94% release by 30 minutes

For the 18 mg claims, the 75-minute threshold is 94%. For the 35 mg independent claim, the 75-minute threshold is 95%, while the dependent claims use a 94% threshold at shorter time points.

This structure gives the patent owner alternative infringement theories. A product may fail the 30-minute limitation but still satisfy the 45-minute, 60-minute, or 75-minute limitation.

Treatment and dosing limitations

Claims 13 and 28 cover acute or chronic pain. Claims 14 and 29 require administration at least once daily. Claims 15 and 30 require that a single unit dose provide perceptible pain relief.

The acute- and chronic-pain language is broad. It does not limit the claims to a particular pain etiology, anatomical site, patient population, or named diagnosis. The once-daily limitation is narrower and may not apply where the product labeling or actual administration involves a different dosing schedule.

The “perceptible pain relief” limitation may create proof issues. In an infringement action, the patent owner would likely need to establish that the accused method produces a perceptible analgesic effect, although the precise evidentiary standard would depend on claim construction and the factual record.

What is the technical significance of the particle-size limitation?

Diclofenac acid has limited aqueous solubility. Reducing particle size can increase surface area and accelerate dissolution. The patent therefore links the physical characteristics of diclofenac acid to the release profile of the oral dosage form.

The claims do not require every particle to fall within the specified range. They require a median particle size on a volume-average basis. Measurement methodology is therefore central. Potential disputes include:

• Whether the measurement is volume-weighted rather than number-weighted.
• Whether the sample is measured before or after formulation.
• Whether agglomerates are counted as individual particles or larger entities.
• Which analytical instrument and dispersion conditions are used.
• Whether the result is reported as D50, median diameter, or another equivalent metric.
• Whether the particle-size distribution remains stable during manufacture and storage.

A generic sponsor could attempt to design around the particle-size element by using diclofenac sodium or potassium, a larger-particle diclofenac acid formulation, a different active form, or a formulation that does not satisfy the claimed median-size measurement. That strategy would require laboratory validation because the claims also contain dissolution limitations.

What products are most closely associated with Patent 9,180,095?

The patent is closely associated with Zorvolex, an oral diclofenac acid product approved in 18 mg and 35 mg strengths for treatment of mild to moderate acute pain and osteoarthritis pain.[2]

Product	Active form	Typical strength	Relationship to Patent 9,180,095
Zorvolex	Diclofenac acid	18 mg, 35 mg	Directly aligned with the claimed dose strengths and nanoparticle technology
Voltaren tablets	Diclofenac sodium	Commonly 25 mg or 50 mg outside the U.S. prescription context	Different salt form; not automatically within the claims
Cataflam	Diclofenac potassium	50 mg	Different salt form and dose architecture
Cambia	Diclofenac potassium for oral solution	50 mg	Different salt, dosage form, and strength
Generic diclofenac sodium	Diclofenac sodium	Multiple strengths	Generally outside the claims unless it somehow satisfies all limitations, including diclofenac acid identity
Generic diclofenac acid	Diclofenac acid	18 mg or 35 mg	Potentially high-risk if particle size and dissolution match the claims

The patent does not cover all diclofenac products. Its claim language is directed to diclofenac acid, not diclofenac sodium or diclofenac potassium. A salt-form distinction is a major design-around pathway, although a product using diclofenac acid as an intermediate or in a complex formulation would require a more detailed infringement analysis.

What is the Orange Book status of the patent?

The FDA Orange Book is the primary source for determining whether a patent is listed against an approved drug and whether the patent is identified as a drug substance, drug product, or method-of-use patent.[3]

Patent 9,180,095 is associated with the Zorvolex patent estate and is directed to method-of-use claims covering administration of specified diclofenac acid doses. Its practical Orange Book significance depends on the patent code and listing information recorded for the relevant Zorvolex approval.

Regulatory issue	Assessment
Reference product	Zorvolex
Active ingredient	Diclofenac acid
Dosage form	Solid oral capsule
Strengths implicated	18 mg and 35 mg
Patent type	Method-of-use and product-performance limitations
FDA pathway for challenge	ANDA Paragraph IV certification or applicable 505(b)(2) pathway
Regulatory risk	Highest for diclofenac acid products matching the claimed strengths and release profile

Orange Book listing does not establish patent validity or infringement. It determines whether a listed patent can trigger the Hatch-Waxman litigation and approval-stay framework.

When does Patent 9,180,095 lose exclusivity?

The patent’s projected statutory expiration is April 2032 based on the patent family’s April 2012 priority position and the term shown in public patent records.[1] The exact enforceable date should be taken from the USPTO patent record after accounting for patent-term adjustment.

Event	Date or period
Earliest priority period	April 2012
Patent grant	November 10, 2015
Projected statutory expiration	April 2032
Earliest ordinary post-expiration entry window	Depends on ANDA approval, litigation, and any other unexpired listed patents
Regulatory exclusivity	Separate from patent term and dependent on FDA approval history

Patent expiration does not guarantee immediate generic launch. Other patents in the Zorvolex family may cover formulations, manufacturing processes, particle-size production, or additional use limitations. A generic applicant must clear the entire relevant patent estate, not only Patent 9,180,095.

How many patents cover Zorvolex and related diclofenac acid technology?

The relevant estate includes more than Patent 9,180,095. Public patent records identify related U.S. patents directed to diclofenac acid compositions, nanoparticle formulations, methods of treatment, and related manufacturing or performance characteristics.[1][4]

A representative landscape includes:

Patent	General subject matter	Commercial relevance
U.S. 8,546,450	Diclofenac acid compositions and nanoparticle technology	Foundational composition and formulation protection
U.S. 9,180,095	Methods using 18 mg or 35 mg diclofenac acid with particle-size and dissolution limits	Direct method-of-use coverage for Zorvolex-type products
Related continuation or divisional patents	Product, formulation, method, or process limitations	May create overlapping barriers after one patent expires

The precise number of active patents can change through expiration, terminal disclaimers, maintenance-fee events, reexamination, disclaimer filings, and continuation practice. A complete freedom-to-operate review must use the current USPTO Patent Center record, FDA Orange Book, and the product’s approved labeling.

What Paragraph IV challenges and patent litigation affect the product?

A generic applicant seeking approval for an 18 mg or 35 mg diclofenac acid capsule could submit a Paragraph IV certification asserting that the listed patent is invalid, unenforceable, or not infringed. The reference product sponsor could then file a patent-infringement action within 45 days, potentially triggering a 30-month stay of final ANDA approval under the Hatch-Waxman framework.[5]

The most likely dispute points for a Paragraph IV challenge to Patent 9,180,095 are:

1. Whether the accused product contains diclofenac acid rather than a different salt or chemical form.
2. Whether its median particle size is measured on a volume-average basis and falls below the claimed threshold.
3. Whether the finished unit dose meets the exact dissolution test.
4. Whether the proposed label induces administration for acute or chronic pain.
5. Whether the claimed combination would have been obvious in view of prior diclofenac nanoparticle and immediate-release formulation disclosures.
6. Whether the dissolution limitations provide an unexpected therapeutic or pharmacokinetic advantage.
7. Whether the claims are enabled across the full range from greater than 25 nm to less than 5,000 nm.

A generic sponsor may avoid direct method-of-use exposure through a Section viii “skinny label” only if the carved-out labeling removes the patented indication or method and the remaining labeling does not encourage infringement. That option is more difficult where the patent claims the core use of the product for pain treatment rather than a separate, removable indication.

No settlement terms, authorized-generic arrangement, or final judicial determination should be inferred solely from the existence of the patent. Litigation and settlement status must be confirmed from PACER, FDA records, and the latest Orange Book data.

How strong is the patent estate?

Patent 9,180,095 has meaningful commercial scope but a narrower technical perimeter than a broad composition-of-matter patent.

Strengths

• It covers both commercially relevant Zorvolex strengths.
• It combines dose, active form, particle size, and dissolution performance.
• The claims include several nested particle-size and release-time limitations.
• A generic product designed to reproduce the reference product closely may satisfy multiple claims.
• The method claims can apply even if a generic manufacturer avoids copying the brand’s excipients or trade dress.

Vulnerabilities

• The claims require diclofenac acid, not merely diclofenac.
• Particle-size measurement can create reproducibility and claim-construction disputes.
• Dissolution testing is highly protocol-specific.
• The asserted technical features may face obviousness challenges based on known micronization and nanoparticle techniques.
• A generic sponsor may pursue a formulation with a different salt, particle-size distribution, dissolution profile, or labeled use.
• Method-of-use claims can be vulnerable to inducement arguments if the approved label is carefully drafted.

The estate is strongest against a generic that duplicates the 18 mg or 35 mg diclofenac acid product and its release performance. It is weaker against conventional diclofenac salts, topical products, oral solutions, and formulations outside the claimed particle-size or dissolution ranges.

What generic launch scenarios exist?

Scenario 1: Matching diclofenac acid capsule

A generic sponsor launches an 18 mg or 35 mg diclofenac acid capsule with comparable nanoparticle dimensions and dissolution. This presents the highest infringement risk and is the scenario most likely to produce Paragraph IV litigation.

Scenario 2: Alternative diclofenac acid formulation

A sponsor uses diclofenac acid but designs the particle-size distribution or release profile outside the claimed thresholds. Risk remains because testing may show overlap with one or more dependent claims.

Scenario 3: Diclofenac sodium or potassium product

A sponsor uses a different salt form. This substantially reduces literal infringement risk under Patent 9,180,095, although other patents, regulatory requirements, bioequivalence issues, and labeling constraints remain.

Scenario 4: Skinny-label launch

A sponsor removes patented pain indications or dosing instructions where FDA regulations permit a Section viii carve-out. This approach may reduce induced-infringement exposure but cannot eliminate risk if the remaining label encourages the claimed use.

Scenario 5: Authorized generic or settlement entry

An authorized generic agreement or litigation settlement could permit entry before patent expiration. The commercial effect would depend on the entry date, supply terms, launch restrictions, and whether other Zorvolex patents remain enforceable.

What manufacturing and IP barriers remain?

The principal manufacturing barrier is control of diclofenac acid particle size at commercial scale. The sponsor must maintain the claimed volume-average median while preventing agglomeration, growth, or batch-to-batch variation. It must also achieve the required dissolution profile in the finished unit dose.

Potential process barriers include:

• Wet milling or high-energy size reduction.
• Stabilization of nanosized diclofenac acid.
• Control of crystal form and polymorphic behavior.
• Uniform loading into capsules.
• Preservation of dissolution performance during storage.
• Analytical validation of particle-size and dissolution measurements.

A formulation that meets the particle-size range but fails the specified release threshold may avoid literal infringement. The reverse is also true. Both limitations must be evaluated together.

How does Patent 9,180,095 compare with conventional diclofenac patents?

Conventional diclofenac patents often focus on salt selection, enteric coating, topical delivery, sustained release, combination therapy, or particular clinical indications. Patent 9,180,095 instead claims a solid oral diclofenac acid product through measurable physical and dissolution characteristics.

Patent category	Main limitation	Relationship to Patent 9,180,095
Diclofenac sodium composition	Salt identity and dosage form	Usually distinct
Diclofenac potassium composition	Salt identity and rapid delivery	Usually distinct
Enteric-release formulation	Delayed release and gastrointestinal protection	Distinct unless diclofenac acid and claimed testing overlap
Topical diclofenac	Route of administration	Outside solid oral method claims
Nanoparticle diclofenac acid	Particle size and dissolution	Closest technical overlap
Pain-treatment method	Indication and dosing	Overlaps if combined with the claimed formulation

Key Takeaways

• U.S. Patent 9,180,095 covers treatment of pain with 18 mg or 35 mg solid oral diclofenac acid doses.
• The claims require diclofenac acid particles with a volume-average median size greater than 25 nm and below specified upper thresholds.
• The finished unit dose must satisfy a detailed USP basket dissolution test.
• Dependent claims add faster release, smaller particle size, acute or chronic pain, once-daily administration, and perceptible pain relief.
• Zorvolex is the principal commercial product associated with the claim architecture.
• Conventional diclofenac sodium and diclofenac potassium products generally do not satisfy the active-form limitation.
• The projected patent expiration is in April 2032, subject to USPTO patent-term adjustment.
• A generic diclofenac acid product that matches Zorvolex’s dose, particle size, and dissolution profile faces the highest Paragraph IV and infringement risk.
• A complete launch analysis must review related formulation, process, continuation, Orange Book, litigation, and settlement records.

FAQs

Does Patent 9,180,095 cover diclofenac sodium?

No. The claims require diclofenac acid. Diclofenac sodium is a different chemical form and generally would not literally satisfy the active-ingredient limitation.

Can a generic avoid the patent by using 50 mg diclofenac potassium?

Usually, that approach avoids the specific 18 mg and 35 mg diclofenac acid limitations. It remains subject to separate regulatory, formulation, and patent analysis.

Is particle size alone enough to establish infringement?

No. The accused product must satisfy all limitations of an asserted claim, including the dose, solid oral unit-dose format, diclofenac acid identity, particle-size range, dissolution test, and claimed treatment method.

Can a generic launch before 2032 with a Paragraph IV certification?

Potentially. A Paragraph IV certification can lead to litigation, a 30-month approval stay, settlement, or an earlier launch if the sponsor prevails, obtains a favorable resolution, or reaches an agreement with the patent owner.

Does FDA approval establish that a generic infringes Patent 9,180,095?

No. FDA approval and patent infringement are separate determinations. FDA evaluates safety, effectiveness, quality, and bioequivalence. Patent infringement depends on claim scope, product testing, labeling, and the relevant legal record.

References

1. United States Patent and Trademark Office. (2015). U.S. Patent No. 9,180,095: Methods for treating pain using diclofenac acid. https://patents.google.com/patent/US9180095
2. U.S. Food and Drug Administration. (2023). Zorvolex prescribing information. https://www.accessdata.fda.gov
3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/orange-book
4. United States Patent and Trademark Office. (2013). U.S. Patent No. 8,546,450: Nanoparticulate diclofenac compositions. https://patents.google.com/patent/US8546450
5. U.S. Food and Drug Administration. (2024). Abbreviated new drug application process and patent certifications. https://www.fda.gov/drugs/types-applications/abbreviated-new-drug-application-anda

Drugs Protected by US Patent 9,180,095

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Zyla	ZORVOLEX	diclofenac	CAPSULE;ORAL	204592-001	Oct 18, 2013		DISCN	Yes	No						TREATMENT OF PAIN
Zyla	ZORVOLEX	diclofenac	CAPSULE;ORAL	204592-002	Oct 18, 2013		DISCN	Yes	No						TREATMENT OF PAIN

Foreign Priority and PCT Information for Patent: 9,180,095

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Australia	2009901748	Apr 24, 2009

International Family Members for US Patent 9,180,095

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
African Regional IP Organization (ARIPO)	3774
Australia	2010239080
Australia	2014208310
Brazil	PI1014272
Canada	2759123
China	102438610
China	104161743