Scope and Claim Analysis for US Patent 11,576,864 (Ruxolitinib Oral Once-Daily Sustained-Release Matrix with HPMC)
Executive summary: US Patent 11,576,864 is a method-of-treatment claim set covering once-daily oral sustained-release ruxolitinib phosphate formulations for myelofibrosis (including PMF, PV-MF, post-ET-MF), polycythemia vera, and graft-versus-host disease, where the product performance is constrained by plasma exposure shape (Cmax/C12h ≤ 10) and half-life (3.5 to 11 hours in dependent form), and the formulation is constrained by (i) HPMC-based sustained-release matrix former at 10–30% by weight and (ii) a ruxolitinib phosphate dose of 10–60 mg free-base basis. The claim language is tight enough that non-HPMC matrices, immediate-release dosing, different dose ranges, or exposure profiles with higher Cmax/C12h ratios fall outside at least key limitations, creating clear design-around pathways while still offering strong coverage against “same-spec” follow-on oral SR products.
What is US Patent 11,576,864 and what does it claim for ruxolitinib sustained-release?
Answer (scope in one line): The patent claims treating myelofibrosis, polycythemia vera, or graft-versus-host disease with a once-daily oral sustained-release ruxolitinib phosphate dosage form that uses an HPMC sustained-release matrix former (10–30% by weight) and produces a specific exposure profile (mean Cmax/C12h ratio ≤ 10, with optional Cmax/C12h subranges and t1/2 ranges).
Claim type and enforcement posture
- Method-of-treatment (US-style) with product and PK limitations embedded.
- The independent claim requires both patient indication and product/PK performance features. That combination typically gives enforcement leverage in infringement suits framed around the marketed product’s dosing regimen and measured PK characteristics.
Independent claim 1: the “core fence”
Claim 1 requires all of the following elements:
- Patient disease: “a disease selected from myelofibrosis, polycythemia vera, and graft versus host disease”
- Route and regimen: “an oral sustained-release dosage form once per day”
- Formulation composition:
- contains ruxolitinib phosphate
- contains 10% to 30% by weight sustained-release matrix former that is hydroxypropyl methylcellulose
- Dose: ruxolitinib phosphate amount corresponds to 10 to 60 mg free base basis
- Oral suitability: dosage form suitable for oral administration
- PK exposure shape:
- “ratio of mean peak plasma concentration (Cmax) to mean 12-hour plasma concentration (C12h) of ruxolitinib of 10 or less”
In practice, claim 1 is less about “how you make it” and more about what it looks like in the body (Cmax/C12h ≤ 10) plus what polymer system it uses (HPMC at 10–30% by weight).
Which diseases are covered by the claims of US 11,576,864?
Answer: The claims cover myelofibrosis, polycythemia vera, and graft versus host disease, with dependent claims specifying myelofibrosis subtypes.
Indication coverage mapping
| Disease category |
Where it appears in the claim set |
| Myelofibrosis |
Claim 1 and dependent claim 7; subtype dependent claims 8 and through 13 |
| Polycythemia vera |
Claim 1 and dependent claim 14; specific dose-linked dependents 15–19 |
| Graft versus host disease |
Claim 1 and dependent claim 20; specific dose-linked dependents 21–25 |
Myelofibrosis subtype granularity
Claim 8 narrows myelofibrosis to:
- primary myelofibrosis (PMF)
- post-polycythemia vera myelofibrosis (PV-MF)
- post-essential thrombocythemia myelofibrosis (post ET-MF)
This matters for infringement because it creates indication-specific coverage even if a challenger contests general “myelofibrosis” language.
What are the key formulation limitations in US 11,576,864?
Answer: The patent requires an HPMC-based sustained-release matrix at 10–30% by weight, with ruxolitinib phosphate dosed to 10–60 mg free-base basis per unit.
Hydroxypropyl methylcellulose (HPMC) constraint
- Dependent coverage is not explicitly subdividing HPMC grade or viscosity, but the claim is explicit that the sustained-release matrix former is:
- hydroxypropyl methylcellulose
- And that it is present at:
Infringement sensitivity:
- A product with HPMC outside 10–30% by weight is at risk of noninfringement for at least claim 1’s composition element.
- A product that uses a different sustained-release matrix former (e.g., ethylcellulose, Eudragit, PEO/PEO blends) is at risk even if dosing and PK match, because the claim requires the matrix former to be HPMC.
Ruxolitinib phosphate dose on a free-base basis
Claim 1 requires:
- 10 to 60 mg ruxolitinib free base basis
Dependent dose claims specify discrete embodiments:
- Claim 2: 10 mg
- Claim 3: 20 mg
- Claim 4: 30 mg
- Claim 5: 40 mg
- Claim 6: 50 mg
Coverage implication:
- The independent claim covers the full 10–60 mg range; dependents provide additional granularity for specific strengths that may map to commercial product strengths.
Dosage form type
Claim 30 specifies:
Practical effect:
- If a competitor uses a different oral sustained-release form factor (e.g., oral multiparticulate in sachets without being a tablet/capsule, or an implant), it may avoid at least this dependent limitation. But claim 1 does not restrict to tablet/capsule, so the main “shape” remains the PK and HPMC constraints.
How does the Cmax/C12h ratio limitation define the sustained-release performance scope?
Answer: Claim 1 requires a mean Cmax/C12h ≤ 10, with dependent claims narrowing to 1–10 and 2–7, plus a half-life window.
Exposure shaping: Cmax/C12h
- Claim 1: Cmax/C12h 10 or less
- Claim 26: Cmax/C12h 1 to 10
- Claim 27: Cmax/C12h 2 to 7
Design-around vector:
- A challenger can aim for a higher Cmax/C12h ratio (for example, boosting late concentrations less relative to peak), while still calling the product “sustained-release” clinically. The legal question becomes whether the competitor’s measured exposure meets the mean ratio limits.
Half-life support
- Claim 28: mean t1/2 from 3.5 to 11 hours
- Claim 29: mean t1/2 from 4 to 8 hours
These are typical sustained-release “PK fit” constraints. They become additional gates for dependent claim coverage and can be used to argue noninfringement if the competitor’s SR produces different terminal kinetics.
What is the overall claim strength posture for US 11,576,864?
Answer: Strong coverage against “same-spec” SR ruxolitinib products because the independent claim ties together (i) indication, (ii) dosing regimen (once daily), (iii) HPMC 10–30% matrix former, (iv) unit dose range, and (v) PK exposure ratio Cmax/C12h ≤ 10. Claim strength is weaker against products that swap matrix formers or change PK profile out of the specified ratios.
What must a plaintiff prove (practically)
For infringement of claim 1, the patentee generally needs evidence that the accused product:
- is administered once daily as an oral sustained-release form,
- contains ruxolitinib phosphate with HPMC as the sustained-release matrix former at 10–30% by weight,
- is dosed within 10–60 mg free base per unit,
- is used to treat one of the specified indications in humans,
- yields a mean PK profile with Cmax/C12h ≤ 10.
This “tight bundle” makes the claim defensible when the accused product has internal/CMC alignment and clinical PK consistent with the claim.
What makes it vulnerable
- If the accused product uses a different sustained-release matrix former or outside 10–30% HPMC.
- If PK assessments show Cmax/C12h above 10 (or outside the dependent ranges).
- If a competitor markets only for indications not covered or if the asserted claim relies on specific dosing for a covered indication.
- If the dosing form is outside tablet/capsule (for dependent claim 30) and claim 1 is not asserted, though claim 1 itself does not impose form-factor limits beyond “suitable for oral administration.”
How many claim limitations are there, and which ones are most “litigation-sensitive”?
Answer: The independent claim has six major limitation clusters. The most litigation-sensitive are the HPMC weight fraction and PK Cmax/C12h ratio, because they are objective and require testing or disclosure-based proof.
Limitation clusters (claim 1)
- Indication (myelofibrosis / PV / GVHD)
- Once-daily oral sustained-release regimen
- Composition: ruxolitinib phosphate
- Composition: HPMC as sustained-release matrix former at 10–30% by weight
- Dose: 10–60 mg free base basis
- PK: mean Cmax/C12h ≤ 10
What formulation “design-around” options are implied by the claim language?
Answer: The claims point to three direct levers for avoiding infringement: polymer system, polymer fraction, and PK exposure ratio.
1) Swap or dilute away from HPMC 10–30% by weight
- Use a different sustained-release matrix former (even if still hydrophilic) to avoid “hydroxypropyl methylcellulose” as the claimed matrix former.
- Adjust HPMC fraction to outside the 10–30% band.
2) Change the administered dose outside the claimed free-base range
- Avoid unit strengths that correspond to 10–60 mg free base (or avoid dosing to stay within that claimed range).
3) Modify PK profile to push Cmax/C12h above 10
- Adjust release kinetics to increase early peak relative to 12-hour concentration.
These vectors are aligned with how claim 1 is written: it is not enough to be “similar sustained-release.” It must pass the polymer and PK numerical thresholds.
How does this patent compare with typical ruxolitinib SR follow-on strategies?
Answer: Typical follow-on strategies target either (a) once-daily convenience and (b) a different release profile to reduce peak-related tolerability issues and improve exposure duration. US 11,576,864 is notable because it encodes both the release-modulating excipient system (HPMC weight %) and an objective PK exposure metric (Cmax/C12h).
Competitor product evaluation framework (for infringement or freedom-to-operate)
- Confirm whether the product is once-daily oral SR
- Confirm whether the matrix former includes HPMC and whether HPMC is 10–30% by weight
- Confirm the unit dose corresponds to 10–60 mg free base
- Confirm clinical mean PK gives Cmax/C12h ≤ 10
- Confirm the claimed indications are the ones actually being treated in the asserted regimen
What patent landscape exists around this claim set (and what is missing from the provided record)?
Answer: A full landscape requires the patent family members, priority chain, and other US/WO grants and applications that cite or are cited by US 11,576,864, plus the Orange Book listings for ruxolitinib products and any Paragraph IV or 505(b)(2) related filings.
Provided record limitation: Only claim text was provided. No jurisdictional filing data (assignee, priority date, publication number, family member IDs), no citing/cited relationship data, and no FDA regulatory history were provided. Without those, a complete cross-patent landscape with quantified expiration dates and litigation/ANDA timelines cannot be generated from the given information.
Key Takeaways
- Claim 1 is a tight “combination claim”: indication + once-daily oral sustained-release + HPMC (10–30% w/w) + 10–60 mg free-base + PK Cmax/C12h ≤ 10.
- Dependent claims add further numerical gates: specific strength embodiments (10, 20, 30, 40, 50 mg) and narrower exposure windows (Cmax/C12h 1–10 and 2–7; t1/2 3.5–11 and 4–8 hours).
- Most infringement-sensitive elements are the HPMC weight fraction and the measured mean PK ratio.
- Design-arounds implied by the claim text: change the matrix former away from HPMC or outside 10–30% w/w, avoid the 10–60 mg free-base dosing band, or engineer a PK profile with Cmax/C12h > 10.
FAQs
1) Does US 11,576,864 protect any ruxolitinib SR product, or only HPMC-based formulations?
Only formulations where the sustained-release matrix former is hydroxypropyl methylcellulose and present at 10–30% by weight fall within claim 1.
2) Is Cmax/C12h required in all claims?
Claim 1 includes Cmax/C12h ≤ 10, and dependent claims refine that ratio; therefore the Cmax/C12h limitation is foundational across the claim structure you provided.
3) What happens if a product is once-daily oral SR but has slightly different half-life?
Claim 1 does not require a t1/2 window, but dependent claims 28–29 do. A competitor could still avoid dependent-claim coverage while still potentially falling under claim 1 if Cmax/C12h ≤ 10 and other limitations match.
4) Are specific ruxolitinib strengths covered only at 10–50 mg, or does claim 1 also cover 60 mg?
Claim 1 covers 10–60 mg free-base basis. Dependent claims list 10, 20, 30, 40, and 50 mg.
5) Do the claims cover both PMF and post-PV or post-ET myelofibrosis?
Yes. Claim 8 expressly includes PMF, PV-MF, and post-ET-MF as covered myelofibrosis subtypes.
References (APA)
- US Patent 11,576,864. Claims as provided by user prompt.
