US Patent 11,337,967 Landscape and Claim Scope: CYP3A4 Substrates With Posaconazole “Washout” Delay
Executive summary: US 11,337,967 claims a patient dosing “restart” method for multiple CYP3A4 substrate drugs (tacrolimus, abemaciclib, encorafenib, larotrectinib, palbociclib, lorlatinib, axitinib, irinotecan) after posaconazole discontinuation, requiring a delay (at least 9 days) before administering the substrate drug. The claim set is structured around a single clinical design variable (the post-inhibitor delay window) and a fixed inhibitor identity (posaconazole), with disease/indication support and dosage timing ranges used to narrow coverage. This design can create strong barriers to “workaround” regimens that use other antifungals or other timing, but it limits enforceability where competitors use different inhibitors, dose-substrate selections outside the enumerated list, or alternative washout models that fall outside the claimed delay ranges.
What does US 11,337,967 claim for CYP3A4 substrates after stopping posaconazole?
Core claim architecture (Claim 1): A method for treating a patient who needs a CYP3A4 substrate drug by first treating with posaconazole (a strong CYP3A4 inhibitor), then:
- Stopping posaconazole treatment;
- Delaying administration of the CYP3A4 substrate drug for at least 9 days after stopping posaconazole (the dose is what the patient would receive based on age/condition absent inhibitor);
- Administering the CYP3A4 substrate dose after the delay.
Fixed inhibitor constraint: posaconazole is required. Claims are not written as a class claim to “strong CYP3A4 inhibitors” generally. The disclosed workaround is to avoid posaconazole.
Variable that controls scope: the post-posaconazole delay period. Dependent claims lock additional timing variants.
Claim 1 anchor points that drive enforceability
- Patient-directed method claim: “method of treating a patient” with a dosing regimen sequence.
- Two-part causality: (i) the patient was treated with posaconazole; (ii) the dosing of the CYP3A4 substrate occurs with a specific delay after stopping posaconazole.
- Dose normalization: the dose administered “is the dose the patient would have received” absent the inhibitor, implying the claim is directed to restoring substrate exposure after the washout rather than chronic coadministration.
- Enumerated substrate drugs: tacrolimus, abemaciclib, encorafenib, larotrectinib, palbociclib, lorlatinib, axitinib, irinotecan.
Practical claim interpretation for litigation
- “Stopping” is a factual dosing event: infringement hinges on whether posaconazole was discontinued and when.
- “At least 9 days” means any delay ≥9 days satisfies the minimum threshold, but narrower dependent claims aim to capture exact timing and specific day ranges.
- “Selected from the group” in Claim 1 means substrate selection is a claim limitation. A regimen using a different CYP3A4 substrate not in the list likely avoids Claim 1, absent doctrine-of-equivalents arguments.
Which CYP3A4 substrate drugs are covered by US 11,337,967?
Claim 1 lists eight CYP3A4 substrate drugs. Coverage for each comes only when the substrate is one of these drugs and is administered after stopping posaconazole with the claimed delay.
| Claim 1 CYP3A4 substrate drug (US 11,337,967) |
Therapy area signals |
| tacrolimus |
transplantation immunosuppression |
| abemaciclib |
HR+/HER2- metastatic breast cancer (CDK4/6) |
| encorafenib |
BRAF V600E/K melanoma and BRAF V600E CRC |
| larotrectinib |
NTRK fusion solid tumors |
| palbociclib |
HR+/HER2- metastatic breast cancer (CDK4/6) |
| lorlatinib |
ALK-positive metastatic NSCLC |
| axitinib |
advanced renal cell carcinoma |
| irinotecan |
metastatic colorectal cancer and solid tumor regimens |
What delay does US 11,337,967 require after stopping posaconazole?
Minimum delay coverage
- Claim 1: delay of at least 9 days after stopping posaconazole before dosing the substrate drug.
Exact timing dependent claims
- Claim 2: delay 9 days
- Claim 3: delay 10 days
- Claim 4: delay 11 days
- Claim 5: delay 14 days
Range dependent claims
- Claim 6: 9–28 days
- Claim 7: 9–42 days
- Claim 8: 9–21 days
- Claim 9: 14–28 days
Overlap dynamics: All range claims sit inside the Claim 1 “≥9 days” umbrella, but they materially affect infringement and damages because they permit plaintiff to select the narrowest fit to the accused facts.
How broad is US 11,337,967’s indication coverage in Claim 10?
Claim 10 adds a disease/condition limitation “wherein the patient is treated for a disease or condition selected from the group consisting of …” and lists multiple clinical settings. It is still a single claim element type (indication), but it expands the method’s target population.
Claim 10 disease/condition basket
- Transplantation
- HR-positive, HER2-negative advanced or metastatic breast cancer
- HR-positive, HER2-negative advanced or metastatic breast cancer with disease progression following endocrine therapy
- Unresectable or metastatic melanoma with BRAF V600E or V600K mutation
- Metastatic colorectal cancer with BRAF V600E mutation
- Adult and pediatric solid tumors with NTRK gene fusion without known acquired resistance mutation, where metastatic or surgery likely causes severe morbidity, with no satisfactory alternatives or progressed after treatment
- HR-positive, HER2-negative advanced or metastatic breast cancer in combination with:
- an aromatase inhibitor as initial endocrine-based therapy in postmenopausal women or in men
- fulvestrant in patients with disease progression following endocrine therapy
- Metastatic non-small cell lung cancer with ALK-positive
- Advanced renal cell carcinoma
- Metastatic adenocarcinoma of the pancreas
Enforcement implication
Even though Claim 10 is dependent, it can matter where the substrate choice is not one-to-one with an indication. A plaintiff can align accused use with the relevant basket to support method-of-treatment framing.
How strong is the scope against “substance” workarounds (other inhibitors)?
Posaconazole is the inhibitor identity in Claim 1. That is a narrow drafting choice and is the primary carve-out opportunity for competitors.
Regimen swap that likely avoids coverage
- Replace posaconazole with another antifungal that is not “posaconazole” (even if it is also a CYP3A4 inhibitor).
- Use a therapeutic strategy that does not include posaconazole as the “strong CYP3A4 inhibitor treatment” step.
Because the claim is not written as “strong CYP3A4 inhibitor” broadly, competitor logic will likely focus on switching the inhibitor.
What generic entry risks exist for competitors using the same substrate drugs?
Because this is a method claim tied to timing after posaconazole discontinuation, generic substrate manufacturers face the following risk profile:
- Substrate generics alone do not infringe; infringement requires the full method steps, including:
- patient treated with posaconazole, stopping it,
- then waiting at least 9 days,
- then dosing the substrate selected from the enumerated list.
- If generics are prescribed within the claimed washout model, risk shifts to prescribing and labeling practices, not only manufacturing.
- If the accused regimen uses different timing (for example, earlier than 9 days), Claim 1’s minimum delay is a clear factual defense.
What “timing workarounds” are most relevant under the claim set?
Accused regimens are most likely to be attacked or defended on whether the post-posaconazole delay duration matches the claimed sequence.
Potential avoidance strategies
- Delay less than 9 days after stopping posaconazole.
- Delay ≥9 days but use substrate drugs not listed in Claim 1.
- Use listed substrate drugs but a different inhibitor (not posaconazole).
- Use the method but with a patient population not meeting the Claim 10 basket where that dependent claim is asserted.
How would US 11,337,967 likely be asserted in Hatch-Waxman Paragraph IV (small molecule)?
Method claims can be asserted against ANDA filers indirectly through:
- alleged inducement or infringement by post-approval prescribing and dispensing practices, and/or
- Orange Book-listed patents associated with drug products if the patent is listed for a particular NDA/strength.
However: the enforceability and litigation traction depend on Orange Book listing status and the identity of the “drug” for which the patent is listed. The claim text you provided does not establish which NDA/ANDA product is tied to 11,337,967 in the Orange Book.
What does the claim focus imply about manufacturing/IP barriers?
This is not a process or formulation manufacturing claim. Barriers are more likely to arise from:
- clinical dosing protocols,
- label language and healthcare provider instruction,
- insurer or guideline adoption of specific washout timing after posaconazole.
If a competitor builds a regimen that reduces reliance on the claimed “restart delay” (or uses other inhibitors), it can reduce infringement exposure without changing manufacturing.
What does a competitor’s drug-labeling strategy need to do to avoid infringement risk?
For any company planning a new label, a clinical program, or an indication update that involves co-management with posaconazole, risk control will typically track:
- whether posaconazole appears in clinical decision pathways,
- what washout timing is recommended after discontinuation,
- whether timing differs from “at least 9 days” thresholds (for Claim 1) and from the specific exact/range dependent claims.
How does US 11,337,967 compare with typical CYP3A4 interaction patents?
Many CYP3A4-related patents claim:
- dose reductions during coadministration,
- pharmacokinetic thresholds,
- formulation modifications (less common for interaction management),
- generic interaction management language.
US 11,337,967 differs by requiring:
- a specific inhibitor identity (posaconazole),
- a specific patient dosing sequence after inhibitor stop,
- and a specific minimum washout threshold.
That structure shifts the litigation battlefield from PK modeling to adherence to a dosing timeline.
Patent landscape mapping: how many “adjacent” patent types could cluster around this one?
Based on the claim composition, a typical surrounding estate (not provided here) would commonly include:
- additional dependent claims with other delay windows,
- claims tied to other CYP3A4 substrates (beyond the enumerated list),
- claims tied to different strong inhibitors,
- claims directed to specific combination regimens (substrate + posaconazole) during coadministration,
- label-support patents for specific indications (transplantation vs oncology).
But the only hard scope provided is the claim text for US 11,337,967, so the mapping below is limited to “what the estate likely covers” rather than listing specific other patent numbers. No other patent numbers can be supplied without a document record.
Within US 11,337,967 itself
- independent claim: Claim 1 (posaconazole + ≥9-day delay + enumerated substrates)
- narrowers: Claims 2–5 (exact delays), 6–9 (ranges), 10 (indication basket), 11–18 (substrate-specific dependent claim hooks)
Key takeaways on claim scope and likely litigation leverage
- Strong central limitation: posaconazole as the inhibitor and a ≥9-day restart delay for listed CYP3A4 substrates.
- Workaround pressure point: switch inhibitor away from posaconazole or shift restart earlier than 9 days.
- Claim coverage is “substrate-enumerated”: use of a CYP3A4 substrate not in the list can avoid coverage for Claim 1.
- Dependent timing claims create multiple infringement “snapshots”: exact day and range claims let a plaintiff fit the accused washout facts tightly.
- Dependent indication claim (Claim 10) broadens patient relevance across transplantation and multiple oncology targets, including NTRK, ALK, BRAF, HR+/HER2-, and axitinib indications.
FAQs
1) Does US 11,337,967 cover coadministration of posaconazole with the CYP3A4 substrate drug?
No. The method requires stopping posaconazole first, then delaying the substrate administration after the stop event.
2) If a regimen waits 8 days after stopping posaconazole, is it outside Claim 1?
Yes. Claim 1 requires “at least 9 days” after stopping posaconazole.
3) Is lorlatinib covered if used as a CYP3A4 substrate after posaconazole with a 14-day delay?
Yes. Lorlatinib is enumerated in Claim 1, and a 14-day delay satisfies Claim 5 and is within the range dependent claims.
4) Can a competitor avoid infringement by using a different antifungal instead of posaconazole?
If the regimen does not include posaconazole as the stopping inhibitor step, it can avoid the specific inhibitor limitation of Claim 1.
5) Are tacrolimus and irinotecan treated differently under the claim?
No. They are both enumerated as acceptable CYP3A4 substrate drugs under Claim 1; differences are mainly in indication and dosing context rather than claim structure.
References
- United States Patent 11,337,967 (claim text provided by user).
