US Drug Patent 9,265,760: Scope, Claim Strength, and U.S. Patent Landscape
US Patent 9,265,760 is directed to an oral extended-release hydrocodone bitartrate product used to treat pain in patients with mild or moderate hepatic impairment, with no starting-dose adjustment versus patients without hepatic impairment, coupled to quantitative guardrails on systemic exposure (AUC0-inf), peak exposure (Cmax), and in vitro dissolution-release behavior. The claims are written as method-of-treatment claims that effectively require the accused product to match both (i) the clinical exposure thresholds and (ii) specific release/dissolution performance parameters.
What does the patent claim cover (end-to-end scope)?
The independent claim (Claim 1) defines a tightly constrained treatment method. The scope has four stacked requirements:
1) Patient condition
- “a patient having mild or moderate hepatic impairment”
2) Drug and formulation
- administering “an oral dosage unit having hydrocodone bitartrate as the only active ingredient”
- the dosage unit “comprises an extended release formulation of hydrocodone bitartrate”
3) Dose logic
- “a starting dose … wherein the starting dose is not adjusted relative to a patient without hepatic impairment”
4) Dose safety exposure envelope (not in Claim 1, but in dependent claims)
- the release profile must meet AUC0-inf and Cmax limits tied to mild and moderate hepatic impairment, relative to subjects without renal or hepatic impairment.
Practical interpretation for competitive targeting
A generic or competitor product would need to be able to show:
- hydrocodone bitartrate alone (no combination salts/actives),
- extended-release profile,
- no starting-dose reduction in mild/moderate hepatic impairment,
- and exposure (AUC0-inf and Cmax) does not exceed stated percentage increases.
The percentage limits create measurable differentiation that can be tested via clinical bridging studies (or, for enforcement posture, via expert analysis of exposure).
What are the core claim elements and how strong are they legally?
Independent claim structure: Claim 1
Claim 1:
- method of treating pain in mild/moderate hepatic impairment
- administer oral extended-release hydrocodone bitartrate-only dosage unit
- starting dose not adjusted versus patients without hepatic impairment
Legal impact: Claim 1 is a framework claim; it captures any extended-release hydrocodone bitartrate-only regimen that meets the “no starting-dose adjustment” requirement. It becomes enforceable in practice through dependent claims that specify exposure-release constraints.
Dependent claims: where the enforceability tightens
Claims 2-4 and 7-9 create the operational “fingerprint”:
AUC0-inf constraints
- Claim 2:
- mild hepatic impairment: AUC0-inf increase ≤ 30%
- moderate hepatic impairment: AUC0-inf increase ≤ 50%
- Claim 3 (tighter):
- mild: AUC0-inf increase ≤ 14%
- moderate: AUC0-inf increase ≤ 30%
Cmax constraints
- Claim 4 (tighter):
- mild: Cmax increase ≤ 9%
- moderate: Cmax increase ≤ 14%
Starting dose amount constraints
- Claim 5: starting dose is “15 mg or more of hydrocodone bitartrate”
- Claim 6: starting dose comprises “20, 30 or 40 mg”
In vitro dissolution release windows
- Claim 7:
- release about 10% to about 30% in first hour
- measured using USP apparatus buffered at pH 6.8
- Claim 8:
- release about 60% to about 98% during first 12 hours
- same dissolution conditions: USP apparatus, pH 6.8
Exposure ranges normalized to 20 mg
- Claim 9:
- reference (no renal/hep impairment): AUC0-inf per 20 mg is *300 to 500 ngh/mL**
- mild hepatic impairment: AUC0-inf per 20 mg is *300 to 570 ngh/mL**
- moderate hepatic impairment: AUC0-inf per 20 mg is *300 to 700 ngh/mL**
- Claims 10-11 (narrower sub-ranges):
- Claim 10: reference no impairment *317 to 465 ngh/mL**
- Claim 11: moderate hepatic impairment *352 to 666 ngh/mL**
Alternate independent claim set: Claims 12-19
Claim 12 is another method claim with the same treatment framing, but it folds the exposure constraints directly into the independent claim body:
- mild/moderate hepatic impairment
- oral extended-release hydrocodone bitartrate-only
- release profile meets:
- mild AUC0-inf increase ≤ 14%
- moderate AUC0-inf increase ≤ 30%
- mild Cmax increase ≤ 9%
- moderate Cmax increase ≤ 14%
Claims 13-19 then mirror Claims 5-11 and 7-9 with similar dissolution windows and AUC/Cmax bounds.
Claim set architecture: “two independent anchors” plus a lattice of dependents
- Anchor A (Claim 1 + dependents): captures “no starting-dose adjustment” logic; dependents define clinical exposure ceilings.
- Anchor B (Claim 12 + dependents): builds the exposure ceilings directly into the independent claim; dependents narrow dosage and dissolution behavior.
This dual-anchor design improves enforcement leverage:
- If a party argues about “no dose adjustment,” Anchor A may still apply via dependents.
- If a party disputes the starting-dose concept, Anchor B can still apply based on the exposure profile requirements embedded directly in Claim 12.
Where exactly are the quantitative “tripwires” in this patent?
The numerical tripwires are the strongest evidence for both validity and infringement testing because they can be operationalized.
Exposure limits tied to hepatic impairment
| Claim |
Metric |
Mild hepatic impairment |
Moderate hepatic impairment |
Comparison reference |
| 2 |
AUC0-inf increase |
≤ 30% |
≤ 50% |
vs subjects “not suffering from renal or hepatic impairment” |
| 3 |
AUC0-inf increase |
≤ 14% |
≤ 30% |
same reference |
| 4 |
Cmax increase |
≤ 9% |
≤ 14% |
same reference |
| 12 |
AUC0-inf increase |
≤ 14% |
≤ 30% |
same reference |
| 12 |
Cmax increase |
≤ 9% |
≤ 14% |
same reference |
Starting dose constraints
| Claim |
Requirement |
| 5 |
starting dose ≥ 15 mg hydrocodone bitartrate |
| 6 |
starting dose is 20, 30 or 40 mg hydrocodone bitartrate |
Dissolution-release windows (USP, pH 6.8)
| Claim |
Timepoint window |
Release window |
| 7 |
first hour |
about 10% to about 30% of hydrocodone |
| 8 |
first 12 hours |
about 60% to about 98% of hydrocodone |
AUC0-inf ranges per 20 mg hydrocodone bitartrate
| Claim |
Population |
AUC0-inf per 20 mg (ng*h/mL) |
| 9(1) |
no renal/hep impairment |
300 to 500 |
| 9(2) |
mild hepatic impairment |
300 to 570 |
| 9(3) |
moderate hepatic impairment |
300 to 700 |
| 10 |
no renal/hep impairment |
317 to 465 |
| 11 |
moderate hepatic impairment |
352 to 666 |
Does the claimset effectively force an “exposure-controlled extended-release” profile?
Yes. Even if a product matches the high-level definition (extended-release hydrocodone bitartrate only), infringement at the dependent level requires that the release profile produces exposure outcomes that do not exceed specified increases in hepatic impairment.
This is critical: the patent does not merely claim a formulation structure. It claims a method defined by pharmacokinetic exposure limits that are tied to hepatic impairment status. That reduces the degree to which a competitor could argue that different excipients still yield the same clinical outcomes unless those outcomes remain within the specified windows.
What is the competitive infringement surface area (what designs would be “in” vs “out”)?
Likely “in-scope” design space
A product is more likely to fall in-scope if it meets all of the following:
- Extended-release hydrocodone bitartrate-only oral unit
- No starting dose reduction in mild/moderate hepatic impairment (as claimed)
- Mild/moderate hepatic impairment exposure increases are kept within:
- AUC0-inf ≤ 30% / 50% (Claim 2) or ≤ 14% / 30% (Claim 3, 12)
- Cmax ≤ 9% / 14% (Claim 4, 12)
- In vitro release behavior aligns with:
- ~10-30% in first hour at USP buffered pH 6.8
- ~60-98% by hour 12 at same conditions
Likely “out-of-scope” design space
A product is likely to fall outside if any of these fails:
- Combination products (hydrocodone bitartrate with another active) do not satisfy “only active ingredient.”
- Immediate-release products do not satisfy “extended release formulation.”
- Products that require starting-dose reduction in hepatic impairment, either by label or by study design aligned to exposure control, contradict the “starting dose is not adjusted” premise in Claim 1.
- Formulations whose hepatic-impairment exposure elevates AUC0-inf beyond the specified percentage limits or Cmax beyond those limits are outside the tighter dependent claims.
How does this patent fit within the broader U.S. hydrocodone ER patent landscape?
A complete patent landscape requires the actual bibliographic record (assignee, filing and issuance dates, related applications, and citation graph) for US 9,265,760, plus cross-linked U.S. continuations, divisionals, and relevant Orange Book listings. The prompt provides only claim text and does not provide the patent’s publication number, assignee, or family identifiers needed to map forward citations and check competing ER hydrocodone bitartrate patents.
Under these constraints, an accurate, end-to-end “landscape” (expiration clustering, overlapping method-vs-composition scope, or identify closest claim sets) cannot be produced from the provided information.
Accordingly, the landscape analysis below is confined strictly to what can be derived from the claim set itself: the technical and legal differentiators that define how this patent is likely to overlap with other U.S. hydrocodone ER intellectual property.
Landscape: what claim types does this patent overlap with across the market?
Even without family mapping, this claimset indicates overlap with two common IP categories in opioid ER development:
1) PK/Exposure-guardrail patents
- Many hydrocodone ER strategies in the U.S. focus on controlling systemic exposure differences across subpopulations (hepatic, renal, elderly).
- Here the differentiator is the explicit numeric exposure delta ceilings in hepatic impairment and the coupling to “no starting-dose adjustment.”
2) Dissolution-requirement patents
- The claims include explicit USP dissolution release fractions at pH 6.8 with time windows (first hour and first 12 hours).
- That indicates an intention to tie clinical performance back to a formulation-level release profile that can be monitored during development and post-approval comparability.
3) Dose-selection strategy within labeling-relevant constraints
- Starting dose thresholds (>=15 mg and specific 20/30/40 mg) suggest the patent is anchored to a dosing regimen intended for hepatic-impaired patients without the usual down-titration.
What is the practical “freedom to operate” implication of the claim design?
For an ER hydrocodone bitartrate product seeking market entry for mild/moderate hepatic impairment dosing without adjustment, the claim set signals that FTO hinges less on generic equivalence at the active ingredient level and more on matching:
- PK results across hepatic impairment phenotypes, and
- dissolution release timing at USP pH 6.8,
- plus the operational dosing premise.
A product can be bioequivalent in average terms but still fail the specific percentage increase boundaries in hepatic impairment, placing it outside the dependent claim coverage but potentially within the independent claim if “no starting-dose adjustment” can be shown and exposure requirements are argued through doctrine-of-equivalents theories. The presence of narrow dependent claims, however, makes direct infringement analysis highly outcome-determinative.
Key Takeaways
- US 9,265,760 claims method-of-treating pain with oral extended-release hydrocodone bitartrate only in mild or moderate hepatic impairment with no starting-dose adjustment versus non-hepatic-impairment patients.
- The enforceability hinge points are numeric and testable:
- AUC0-inf increases limited to ≤30%/50% (Claim 2) or ≤14%/30% (Claims 3 and 12) for mild/moderate hepatic impairment.
- Cmax increases limited to ≤9%/14% (Claims 4 and 12).
- Dissolution release windows at USP buffered pH 6.8: ~10-30% in first hour and ~60-98% by hour 12.
- The claims include starting dose constraints: ≥15 mg (Claim 5) and 20/30/40 mg (Claim 6 and equivalents).
- The claim set uses a dual-anchor structure (Claim 1 and Claim 12) to improve coverage depending on whether disputes focus on dosing logic or embedded exposure ceilings.
- A full U.S. patent landscape requires bibliographic family identifiers and citation/Orange Book linkage; those inputs are not present in the prompt, so the analysis here is limited to claim-derived technical overlap.
FAQs
1) Is the patent about the hydrocodone molecule or the formulation?
It is about an oral extended-release hydrocodone bitartrate formulation used in a specific patient group with measured PK exposure limits and USP pH 6.8 dissolution release windows.
2) Does it allow combination products with other active ingredients?
No. It requires hydrocodone bitartrate to be the only active ingredient.
3) What hepatic exposure thresholds matter most for infringement analysis?
The tightest limits are in Claims 3 and 12: AUC0-inf ≤14% (mild) and ≤30% (moderate), and Cmax ≤9% (mild) and ≤14% (moderate).
4) Does the patent require a specific starting dose?
Claim 1 requires “starting dose is not adjusted,” and dependent claims specify dose amounts: ≥15 mg and specifically 20/30/40 mg.
5) Do in vitro dissolution results play a role?
Yes. Dependent claims tie infringement to release fractions in a USP apparatus buffered at pH 6.8: ~10-30% in the first hour and ~60-98% by 12 hours.
References (APA)
[1] Claims text provided in the prompt for U.S. Patent 9,265,760.
