US Patent 9,060,940: Scope, Claims, Expiration, Litigation Risk, and Hydrocodone Patent Landscape

US Patent 9,060,940 is a Purdue Pharma patent directed to once-daily controlled-release hydrocodone treatment methods. Its central limitation is a pharmacokinetic target: a hydrocodone plasma C24/Cmax ratio of approximately 0.55 to 1.0. The patent does not broadly claim every extended-release hydrocodone formulation. It claims administering such a formulation in a manner that produces the specified serum profile and, in claim 19, a W50 duration of 4 to 22 hours.

The patent is most relevant to Hysingla ER and other once-daily extended-release hydrocodone products. Its estimated patent-term expiration is April 8, 2027, subject to the official USPTO term calculation and any applicable patent-term adjustment.[1]

What does US Patent 9,060,940 protect?

The patent protects a method of providing pain relief by administering hydrocodone once daily in a controlled-release formulation that produces defined pharmacokinetic characteristics in the patient.[1]

The independent claims contain four core requirements:

Claim element	Claims affected	Scope
Patient requires effective pain relief	1, 18, 19	Therapeutic-use limitation
Oral once-daily administration	1, 18, 19	Excludes twice-daily or nonoral regimens
Controlled-release hydrocodone formulation	1, 18, 19	Requires extended or controlled release
C24/Cmax ratio of about 0.55 to 1.0	1, 18, 19	Principal pharmacokinetic limitation
W50 of 4 to 22 hours	19, 20	Additional duration limitation
Hydrocodone or pharmaceutically acceptable salt	1, 19	Claim 18 narrows to hydrocodone bitartrate

The patent therefore has method-of-treatment scope rather than a simple composition claim. A product may contain hydrocodone and controlled-release excipients without infringing unless its labeled or actual use produces the claimed pharmacokinetic profile under the claimed dosing conditions.

How do the C24/Cmax limitations operate?

C24/Cmax is the plasma concentration of hydrocodone at 24 hours after dosing divided by the maximum observed plasma concentration after dosing.

For example, if Cmax is 100 ng/mL and the 24-hour concentration is 65 ng/mL, the C24/Cmax ratio is 0.65. That result falls within claims 1, 2, 3, 4 and 5.

The dependent claims divide the principal ratio range into narrower overlapping bands:

Claim	C24/Cmax range
1, 18, 19	About 0.55 to about 1.0
2	0.55 to 0.85
3	0.55 to 0.75
4	0.60 to 0.70
5	0.70 to 0.85

The overlapping structure gives the patent multiple infringement theories. A product with a ratio of 0.68 may fall within claims 1, 2, 3 and 4. A ratio of 0.80 may fall within claims 1, 2 and 5.

The use of “about” creates a boundary issue. The patent does not establish a single universally applicable numerical tolerance. A court would likely assess the term in light of the specification, analytical variability, formulation testing, and prosecution history. The uncertainty is material near the 0.55 and 1.0 endpoints.

What does claim 19 add through the W50 limitation?

Claim 19 requires both:

A C24/Cmax ratio of about 0.55 to 1.0; and
A W50 for hydrocodone of between 4 and 22 hours.

Claim 20 narrows the W50 requirement by requiring a W50 of at least 12 hours. The W50 generally refers to the duration for which plasma concentrations remain at or above 50% of Cmax.

Claim 19 is narrower than claims 1 and 18 because a product must satisfy two pharmacokinetic conditions. It may be more difficult for a patent owner to prove infringement, but it may also be more resilient against an invalidity attack based on the broader C24/Cmax-only claims if the combined profile was not disclosed or suggested in the prior art.

What formulations and excipients are protected?

Claims 6 through 12 do not independently claim a particular tablet, capsule, or excipient combination. They narrow the method claims by specifying controlled-release materials or matrix components.

Controlled-release materials

Claim 6 covers formulations containing one or more of the following:

Gums
Cellulose ethers
Acrylic resins
Waxes
Shellac
Oils

Claim 7 narrows cellulose ethers to:

Alkylcellulose
Hydroxyalkylcellulose
Carboxyalkylcellulose

These categories can include commonly used hydrophilic and hydrophobic matrix materials. The claims are not limited to one brand-name excipient or one manufacturing process.

Hydrophobic matrix materials

Claim 8 covers a matrix containing a hydrophobic material with a melting point of approximately 30°C to 200°C.

Claim 9 identifies:

Fatty acids
Fatty alcohols
Glyceryl esters of fatty acids
Waxes
Polyalkylene glycols
Mixtures of those materials

Claim 10 narrows the formulation to a glyceryl ester of a fatty acid.

Cellulose-based matrices

Claim 11 requires microcrystalline cellulose in the matrix. Claim 12 adds hydroxypropylcellulose.

These claims create formulation-specific fallback positions. A generic manufacturer may avoid some dependent claims by using a different matrix architecture, but that does not avoid the independent claims if the product still produces the claimed serum profile.

What are the dosage, salt, and treatment-stage limitations?

Claims 13 and 14 distinguish between administration at two treatment stages:

Claim 13: administration at initiation of therapy
Claim 14: administration at steady state

Claim 15 covers 0.5 mg to 1,250 mg of hydrocodone, while claim 16 narrows the range to 5 mg to 60 mg. Claim 17 specifies hydrocodone bitartrate.

The 1,250 mg upper limit is unusually broad compared with ordinary clinical hydrocodone doses. Claim 16 is more commercially relevant because it overlaps typical once-daily strengths and therapeutic dosing ranges.

Claim 18 separately claims once-daily administration of hydrocodone bitartrate. It is structurally important because it removes the need to rely on the broader “hydrocodone or pharmaceutically acceptable salt” language in claim 1.

When does US Patent 9,060,940 expire?

The patent issued on June 23, 2015. Its estimated expiration date is April 8, 2027, based on the underlying patent-family term.[1] The date should be distinguished from FDA regulatory exclusivity.

Event	Date or period
Patent issue	June 23, 2015
Estimated patent expiration	April 8, 2027
Hysingla ER FDA approval	November 20, 2014
Five-year NCE exclusivity for Hysingla ER	Generally expired in 2019
Patent-based generic-entry barrier	Expected to extend to 2027, subject to litigation and settlements

Patent expiration and FDA exclusivity operate independently. Hysingla ER’s new chemical entity exclusivity did not extend beyond the relevant five-year period, but listed patents could continue to block or delay ANDA approval.[2]

What is the Orange Book status of US Patent 9,060,940?

US Patent 9,060,940 has been associated with Hysingla ER, Purdue’s extended-release hydrocodone product.[2] Orange Book listing status can change through patent-listing updates, product discontinuation, corrections, or FDA determinations.

The practical effect of listing is significant. An ANDA applicant seeking approval for a product that references Hysingla ER must address each listed patent through one of the statutory certification pathways:

Paragraph I: no patent information is listed
Paragraph II: the patent has expired
Paragraph III: the applicant will wait until patent expiration
Paragraph IV: the patent is invalid, unenforceable, or will not be infringed

A Paragraph IV notice can trigger patent litigation under the Hatch-Waxman Act. A timely lawsuit can impose a 30-month stay of approval, subject to statutory exceptions and court action.[3]

Which products and companies face the greatest exposure?

The primary commercial product associated with the patent is Hysingla ER, an extended-release hydrocodone bitartrate product marketed by Purdue Pharma.[4]

Product	Active ingredient	Dosing profile	Relationship to patent
Hysingla ER	Hydrocodone bitartrate	Once daily	Primary reference product exposure
Zohydro ER	Hydrocodone bitartrate	Extended release, historically twice daily	Potentially lower direct exposure if dosing and profile do not meet all limitations
Generic hydrocodone ER	Hydrocodone salt	Depends on proposed label	ANDA applicant must assess listed claims
Immediate-release hydrocodone products	Hydrocodone combinations or single ingredient	Usually multiple daily doses	Generally outside the once-daily controlled-release limitations

Zohydro ER is an important comparator, but the patent’s once-daily requirement limits the relevance of products labeled for twice-daily use. A formulation could still raise risk if its actual or instructed use produces once-daily dosing within the claimed parameters, but label-based infringement analysis would turn on the proposed prescribing instructions and evidence of induced use.

How strong is the patent estate around Hysingla ER?

The estate is stronger as a portfolio than as a single patent. US Patent 9,060,940 focuses on pharmacokinetic treatment parameters. Other Hysingla-related patents have addressed formulation, controlled release, abuse deterrence, and related hydrocodone delivery characteristics.

The principal strengths of the ’940 patent are:

It targets the clinical use of once-daily hydrocodone rather than only a specific excipient.
The overlapping C24/Cmax ranges provide multiple claim positions.
The dependent formulation claims create narrower positions against matrix-based products.
Claim 19 adds W50, creating a second pharmacokinetic marker.
A generic label directing once-daily administration may provide a clear inducement theory if the profile is inherent to the proposed product.

The principal weaknesses are:

The claims depend on pharmacokinetic outcomes that may vary by patient, dose, food effect, assay, and study design.
“About” creates numerical boundary disputes.
The broad C24/Cmax target may be vulnerable to obviousness arguments if prior art disclosed extended-release opioid profiles and routine PK optimization.
The method claims may face divided-infringement issues because the patient performs the administration step.
The formulation limitations may not cover every controlled-release technology.

What Paragraph IV challenges and litigation risks exist?

An ANDA applicant challenging the patent would likely focus on three issues.

Inherent infringement

The applicant could argue that its product does not intentionally target the claimed ratio. Purdue could respond that the ratio is an inherent property of the proposed once-daily formulation and that the approved label directs use that necessarily produces the profile.

The key evidence would include:

Comparative pharmacokinetic studies
C24 and Cmax data
Steady-state and single-dose results
Food-effect studies
Dose proportionality
Interpatient variability
Product specifications and dissolution data

Obviousness

The challenger could combine prior-art disclosures concerning:

Extended-release hydrocodone
Once-daily opioid dosing
Controlled-release matrices
Target plasma concentrations
Sustained analgesia
Conventional PK parameters such as Cmax, Tmax and half-life

The patent owner would argue that the particular C24/Cmax and W50 combination produced a clinically useful duration and was not a predictable result of routine formulation work.

Indefiniteness and enablement

Potential arguments include whether:

“About 0.55” provides a sufficiently definite boundary;
W50 is measured consistently across patients and study conditions;
the disclosure enables the full 0.55 to 1.0 range across all covered hydrocodone formulations; and
“effective pain relief” supplies an objective therapeutic standard.

The commercial risk depends less on the literal breadth of the claims than on whether the reference product’s labeled PK profile is reliably reproduced by the proposed generic.

What generic launch scenarios are possible?

Scenario	Commercial result
No Paragraph IV challenge	Generic approval delayed until patent expiry or a permitted regulatory pathway
Paragraph III certification	Approval generally deferred until April 2027
Paragraph IV with no timely suit	Approval may proceed after statutory notice and regulatory review
Paragraph IV with litigation	Potential 30-month stay and court determination
Settlement with licensed entry	Entry date depends on settlement terms
Successful invalidity or noninfringement defense	Earlier approval and launch possible
Failed challenge	Launch delayed until patent expiry or settlement date

A first-filer may seek 180-day shared or exclusive generic exclusivity, depending on the certification and first-applicant status. The commercial value of the challenge depends on the size of the once-daily hydrocodone market, the number of first filers, settlement restrictions, and whether other patents remain blocking.

Are biosimilar risks relevant to this patent?

No. Hydrocodone is a small-molecule active pharmaceutical ingredient, so the relevant pathway is an ANDA under section 505(j), not a biosimilar application under the Biologics Price Competition and Innovation Act.[3,5]

The relevant competitive risks are:

Generic hydrocodone ER
Alternative extended-release opioid products
Abuse-deterrent opioid formulations
Immediate-release hydrocodone combinations
Nonopioid analgesics and multimodal pain therapies

What geographic coverage does the patent provide?

US Patent 9,060,940 provides protection only in the United States. Comparable protection would require separate national or regional patents in other jurisdictions. Foreign family members may have different claims, prosecution histories, expiration dates, and validity outcomes.

US coverage is most important for:

US manufacture
Importation into the United States
Commercial sale
ANDA approval and launch
Induced use under a US label

A foreign supplier may still face US exposure if it manufactures a product for importation or sale in the United States.

How does US Patent 9,060,940 compare with formulation patents?

The ’940 patent is a pharmacokinetic method patent. A formulation patent generally claims the composition, dosage form, abuse-deterrent architecture, release mechanism, or manufacturing process directly.

Patent type	Main infringement question
’940 method patent	Does the once-daily product produce the claimed C24/Cmax and W50 profile?
Composition patent	Does the product contain the claimed ingredients and amounts?
Dosage-form patent	Does the tablet or capsule have the claimed physical structure?
Manufacturing patent	Was the claimed process used?
Method-of-use patent	Does the label direct the patented therapeutic use?

A generic may design around a formulation patent yet still face the ’940 patent if its alternative formulation produces the claimed serum profile. Conversely, a product may use similar excipients but avoid the ’940 patent if it does not satisfy the pharmacokinetic limitations or once-daily use requirement.

Key Takeaways

US Patent 9,060,940 protects once-daily controlled-release hydrocodone treatment methods.
The central limitation is a C24/Cmax ratio of approximately 0.55 to 1.0.
Claims 4 and 5 create narrower, overlapping ratio positions that may support infringement under different PK results.
Claim 19 adds a W50 requirement of 4 to 22 hours; claim 20 requires at least 12 hours.
The patent includes dependent claims covering cellulose ethers, hydrophobic matrices, fatty materials, microcrystalline cellulose and hydroxypropylcellulose.
The patent is primarily relevant to Hysingla ER and proposed generic once-daily hydrocodone products.
Its estimated expiration date is April 8, 2027.
Generic challengers would likely contest inherent infringement, obviousness, indefiniteness, enablement and the sufficiency of patient-directed use for inducement.
The patent is not relevant to biosimilar regulation because hydrocodone is a small molecule.
Patent risk must be evaluated together with the broader Hysingla ER formulation and abuse-deterrence portfolio.

FAQs

Does US Patent 9,060,940 cover all hydrocodone products?

No. It requires oral once-daily administration of a controlled-release hydrocodone formulation that produces the specified plasma profile. Immediate-release and routinely dosed multiple-times-per-day products generally do not meet those limitations.

Can a generic avoid the patent by using a different excipient?

Possibly, but changing excipients alone may not avoid infringement. The independent claims focus on dosing and pharmacokinetic results. A different formulation can still infringe if it produces the claimed C24/Cmax and W50 values.

Is hydrocodone bitartrate required in every claim?

No. Claims 1 and 19 cover hydrocodone or a pharmaceutically acceptable salt. Claim 17 narrows to the bitartrate salt, and claim 18 specifically requires hydrocodone bitartrate.

Does a C24/Cmax ratio below 0.55 avoid every claim?

It may avoid the disclosed ratio limitations, but the result depends on measurement conditions and the interpretation of “about.” Other Hysingla-related patents could present separate barriers.

Could a company launch before April 2027 after a Paragraph IV challenge?

Yes, if the patent is held invalid or not infringed, if the patent owner does not obtain a statutory stay, or if the parties reach a settlement permitting earlier entry. Other listed patents could still delay launch.

References

U.S. Patent No. 9,060,940. (2015). Methods of treating pain with hydrocodone formulations. United States Patent and Trademark Office.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
Drug Price Competition and Patent Term Restoration Act of 1984, 21 U.S.C. § 355(j).
U.S. Food and Drug Administration. (2014). Hysingla ER prescribing information. Purdue Pharma L.P.
Biologics Price Competition and Innovation Act of 2009, 42 U.S.C. § 262.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2002227383	⤷ Start Trial
Australia	2738302	⤷ Start Trial
Brazil	0115382	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 9,060,940

Summary for Patent: 9,060,940