United States Patent 12,594,273 Scope and Claims: Dihydroergotamine Mesylate Powder Nasal Delivery Device Using Microcrystalline Cellulose
US Drug Patent 12,594,273 is a formulation-and-delivery-device claim set aimed at a nasal powdered dihydroergotamine mesylate product with microcrystalline cellulose (MCC) as the dominant excipient and a performance target tied to Tmax ≤ 30 minutes while eliminating the need for priming. The claim scope is constrained by: (i) drug/excipient weight ranges, (ii) specific powder/device characteristics, and (iii) pharmacokinetic behavior (Tmax). Dependent claims narrow to specific drug loading levels, MCC particle size, and powder unit mass.
What does US Patent 12,594,273 claim for a dihydroergotamine mesylate nasal device?
Claim 1 is the anchor. It covers a nasal delivery device containing a nasal pharmaceutical dosage form comprising:
- Active: dihydroergotamine mesylate
- 6 mg to about 8 mg per nasal dosage form
- Excipient: microcrystalline cellulose
- 40% to 60% w/w of the nasal dosage form
- PK/performance constraint: nasal delivery device provides Tmax ≤ 30 minutes
- Operational constraint: device requires no priming
- Device/dosage form relationship: “nasal delivery device” provides/contains the nasal dosage form meeting these parameters
How infringement risk is structured under claim 1
- A product must meet all elements to read onto claim 1.
- The biggest practical gating elements are the exact composition ranges and the Tmax ≤ 30 minute requirement.
- “Requires no priming” limits coverage against products that do include a priming step (even if composition and Tmax are matched).
Key claim-1 scope elements that courts typically treat as factual proof points
- Whether the product contains MCC at 40–60% w/w
- Whether the DHE mesylate dose is within 6–8 mg
- Whether measured Tmax after nasal administration is ≤ 30 min (typically in a PK study)
- Whether the user workflow includes any priming step
Which formulation ranges in claim 1 control the protected composition?
Claim 1 tightly defines formulation boundaries:
Dihydroergotamine mesylate amount
- 6 mg to ~8 mg per nasal dosage form
Microcrystalline cellulose amount
- 40% to 60% w/w of the nasal dosage form
Performance requirement
- Tmax of DHE mesylate ≤ about 30 minutes
No-priming requirement
- The nasal delivery device requires no priming
Practical consequence
- A near-miss outside the MCC range (for example 35% or 65% w/w MCC) is a clean design-around for claim-1 composition alone.
- A product inside the composition range but with Tmax > 30 min is also a clean design-around.
- Adding priming (even with the same formulation) can avoid the “requires no priming” element.
How do dependent claims 2–4 narrow dihydroergotamine mesylate loading?
Dependent claims specify particular drug loading percentages or exact mg values, tightening coverage around certain exemplified or preferred strengths:
Claim 2
- Dihydroergotamine mesylate present at about 18% w/w
Claim 3
- Dihydroergotamine mesylate present at about 23% w/w
Claim 4
- Dihydroergotamine mesylate present at 6 mg (exact)
Scope effect
- These dependent limitations do not broaden claim 1.
- They narrow to specific embodiments, creating a second “belt” of coverage around particular strength formulations likely aligned with the dose mass and MCC percentage targets.
What powder nasal dosage form and unit-dose limitations are covered in claims 5–6?
Claim 5
- The nasal dosage form is a powder pharmaceutical nasal dosage form
Claim 6
- The nasal dosage form is in a unit dose form
Scope effect
- Claim 1 already calls the dosage form “pharmaceutical nasal dosage form,” but claims 5 and 6 lock the technology to powder and unit-dose formats.
- If a competitor uses a solution/suspension nasal approach, it avoids claims 5 and 6 and may fall outside the overall intended embodiment set even if claim 1 might be asserted broadly through dependent claim strategies (in practice, most assertion strategies center the full dependent chain).
How do claims 7–8 further lock MCC content to 50–60% and 60% levels?
Claim 7
- MCC present at about 50% to about 60% of total dosage form weight
Claim 8
- MCC present at about 60% of total dosage form weight
Scope effect
- These are narrower than claim 1’s 40–60% band.
- They become strong handles for enforcement when accused products sit at the high end of MCC content (50–60% or ~60%).
What is the significance of MCC particle size limits in claims 9–11?
These claims are performance-adjacent because particle size can strongly affect dispersibility, deposition, and absorption kinetics (and therefore Tmax).
Claim 9
- MCC has mean particle size diameter ~100 μm or less
Claim 10
- MCC has mean particle size ~50 μm or less
Claim 11
- MCC has mean particle size ~30 μm or less
Scope effect
- Particle-size limits add an additional layer of design-around.
- A competitor could keep MCC weight percent and drug dose inside ranges yet use an MCC grade above the claimed size threshold to avoid dependent claims 9–11.
Claim strategy insight
- In litigation, particle size is often easier to prove via vendor COAs and lab testing than PK endpoints.
- Claim 9–11 can create staggered infringement positions: if a product matches MCC content but only partially matches particle size, it may still fall under claim 1 but not under dependent coverage.
How do claims 12–13 lock the total powder mass per unit dose?
Claim 12
- Total weight of powder nasal dosage form is about 35 mg
Claim 13
- Total weight is about 30 mg
Scope effect
- These mass limitations align to specific formulation compositions (drug % w/w and MCC w/w).
- They function as additional design-around points against “close but not exact” strengths.
Interdependency with drug % claims
- Claims 2 and 3 specify drug w/w percentages (18% and 23%).
- Claims 12 and 13 specify total unit mass (~35 mg and ~30 mg).
- Together they likely correspond to drug mass boundaries already stated in claim 1 (6–8 mg) and dependent claim 4 (6 mg), producing narrow but commercially meaningful sweet spots.
What methods are covered: administration and treatment claims (claims 14–16)?
Claim 14
- Method of delivering the nasal pharmaceutical dosage form:
- Administer to a nostril using the device of claim 1
Claim 15
- Method of treating a headache:
- Administer to a nostril using the device of claim 1
Claim 16
- Method of claim 14:
- Dosage is administered at a first time and a second time
Scope effect
- Claim 15 ties the formulation/device to a medical use: treatment of headache.
- Claim 16 introduces a dosing regimen concept (two administrations), which can affect infringement for users prescribing/using a dosing schedule.
What is the likely claim “theory of invention” reflected by the limitations?
Across claim 1 and the dependent chain, the protected subject matter centers on a specific combination:
- DHE mesylate dose window (6–8 mg)
- MCC-heavy powder formulation (40–60% w/w)
- Particle size constraints (≤ 100 μm, ≤ 50 μm, ≤ 30 μm in dependent claims)
- Nasal delivery performance (Tmax ≤ 30 min)
- User workflow (no priming)
- Powder unit dose format
That combination suggests the patent is intended to prevent competing nasal powder systems that either:
- do not hit the same dosing/loading composition,
- do not meet the Tmax threshold,
- use priming steps, or
- do not use MCC in the specified amount and/or particle size.
What design-arounds are most direct against claim 1 and the dependent narrowing?
Composition design-around
- Push MCC outside 40–60% w/w
- Push DHE mesylate outside 6–8 mg
PK design-around
- Keep composition close but ensure Tmax > 30 min in measured PK (or via clinical endpoint framing)
Workflow design-around
- Add any form of priming step so the “requires no priming” element is not met
Material-grade design-around
- Use MCC with mean particle size > the dependent thresholds (>100 μm to avoid claim 9; >50 μm to avoid claim 10; >30 μm to avoid claim 11)
- Keep MCC content and drug load but change grade distribution to defeat dependent claim layers
Unit-mass design-around
- Use unit dose total powder mass materially different from ~30 mg or ~35 mg to avoid claims 12–13
How strong is the patent estate for a nasal DHE mesylate product based on these claims alone?
Based on claim text only, enforcement strength rests on the number and specificity of constraints:
- Claim 1 is already multi-factor (dose range + MCC range + Tmax threshold + no-priming + delivery device).
- Dependent claims add multiple additional “knobs” that can create narrower but still enforceable embodiments:
- drug w/w (18%, 23%)
- exact drug mass (6 mg)
- powder unit dose
- MCC subranges (50–60%, 60%)
- particle size thresholds (100/50/30 μm)
- total powder mass (~30 mg, ~35 mg)
- dosing regimen (first and second time)
- treatment of headache
Net effect
- A competitor must avoid a relatively large claim matrix.
- The strongest risk to a competitor is meeting both the composition and Tmax requirements without changing device workflow such as priming.
What is the litigation and exclusivity posture?
No data is provided here to identify:
- Orange Book listings
- FDA application number
- patent expiry dates
- whether any Paragraph IV or biosimilar-style challenges exist
- whether 12,594,273 is listed as an Orange Book “drug product” or “method of use” patent tied to a specific NDA
Because no such records are included in the input, the litigation/exclusivity posture cannot be produced without external source facts.
Key Takeaways
- US 12,594,273 protects a nasal powder unit-dose device delivering dihydroergotamine mesylate with MCC as 40–60% w/w, DHE dose 6–8 mg, and Tmax ≤ 30 minutes.
- The device must require no priming, which is a clear workflow-based design-around lever.
- Dependent claims narrow to specific embodiments: 18% or 23% w/w DHE, 6 mg DHE, MCC at 50–60% or ~60%, MCC particle size ≤100/50/30 μm, and total powder mass ~30 mg or ~35 mg.
- Method claims cover nasal administration using the claim-1 device and treating headache, with a two-dose regimen in claim 16.
FAQs
1) What happens if a competitor matches the DHE and MCC percentages but misses the Tmax threshold?
Claim 1 requires Tmax ≤ 30 minutes; missing Tmax is a straightforward non-infringement pathway for claim 1.
2) Can a competitor avoid infringement by changing MCC particle size while keeping MCC weight percent in range?
Yes. Changing MCC mean particle size to above the dependent thresholds can defeat claims 9–11 even if claim 1 composition is matched.
3) Does claim scope require a powder formulation?
Claim 5 explicitly limits dependent coverage to powder; overall protection is centered on a nasal dosage form, but the powder/unit-dose format is expressly claimed in dependent claims.
4) How do the no-priming limitation and priming devices interact?
If a competitor’s device has a priming step, it avoids the “requires no priming” element of claim 1, even if composition and Tmax are similar.
5) Are dosing regimens part of the independent claim?
No. The two-time regimen appears in claim 16, which is dependent on claim 14, so regimen matters for that dependent claim chain.
References
- United States Patent US 12,594,273 (claims as provided in prompt).
