United States Patent 12,582,620: Scope, Claim Structure, and Practical Patent Landscape
United States Patent 12,582,620 claims an oral pharmaceutical solution with a tightly defined lisdexamfetamine dimesylate concentration, aqueous buffer/cosolvent system, pH window, and a glycol-type cosolvent. The claim set builds a broad independent claim (Claim 1) around the composition concept, then narrows along three main axes: cosolvent identity, cosolvent concentration, and buffer chemistry, with optional containment via preservative (Claim 20).
What does the core independent claim cover? (Claim 1)
Claim 1 is the sole independent claim and defines the core composition:
- Dosage form: oral pharmaceutical solution
- Active: lisdexamfetamine dimesylate at 10 mg/mL
- Vehicle: pharmaceutically acceptable aqueous carrier comprising:
- pH window: 6.0 to 9.0
- Cosolvent type: cosolvent comprises a glycol
Practical scope: Any oral solution matching:
- lisdexamfetamine dimesylate at 10 mg/mL,
- buffered aqueous solution,
- glycol cosolvent present,
- pH in 6.0-9.0,
falls within Claim 1, regardless of the specific glycol species unless narrowed by dependent claims asserted in litigation.
How do dependent claims narrow scope?
Cosolvent identity and concentration tiers
Claim 2 adds a specific cosolvent family and sets a general concentration envelope:
- Cosolvent: propylene glycol, low molecular weight polyethylene glycol, or mixture
- Total cosolvent: 5 mg/mL to 300 mg/mL
Claims 3-6 provide layered concentration bands for “low molecular weight polyethylene glycol” and for generic glycol system:
- Claim 3: cosolvent comprises low molecular weight polyethylene glycol
- Claim 4: total cosolvent 5 mg/mL to 300 mg/mL
- Claim 5: total cosolvent 50 mg/mL to 250 mg/mL
- Claim 6: total cosolvent 100 mg/mL to 200 mg/mL
Claims 7-8 narrow the pH window:
- Claim 7: pH 6.0 to 8.5
- Claim 8: pH 6.5 to 8.0
Claims 9 and 11-13 specify additional cosolvent selection:
- Claim 9: cosolvent comprises propylene glycol
- Claim 11: (under Claim 7) cosolvent comprises low molecular weight polyethylene glycol
- Claim 12: (under Claim 7) cosolvent comprises propylene glycol
- Claim 13: (under Claim 7) cosolvent further comprises glycerol, sorbitol, or xylitol
Claim 10 adds optional polyol co-components:
- cosolvent further comprises glycerol, sorbitol, or xylitol
Scope implication:
- Claim 1 is the broadest: “glycol” plus pH/buffer rules.
- Claims 2, 3, 9, 11-13, 10 impose identity constraints that can be used to capture formulations using specific excipient selections or mixtures.
- Claims 4-6 create multiple overlapping concentration ranges that are particularly useful in enforcement because drug products often select one target concentration band for formulation stability.
Buffer chemistry tiers
Claim 14 lists an extensive set of buffer components:
- buffer comprises:
ascorbic acid, acetic acid, tartaric acid, citric acid monohydrate, sodium citrate, potassium citrate, acetic acid, sodium acetate, sodium hydrogen phosphate, sodium dihydrogen phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate
or mixtures
Claim 15 narrows buffer to:
- phosphate buffer solution
Claims 16-19 mirror buffer options while tethering to dependent bases (notably pH or cosolvent selection depending on the claim chain):
- Claim 16: (under Claim 7) same buffer list as Claim 14
- Claim 17: (under Claim 7) phosphate buffer solution
- Claim 18: (under Claim 12) same buffer list as Claim 14
- Claim 19: (under Claim 12) phosphate buffer solution
Scope implication: The buffer list is broad and enumerated, which reduces “design-around” leverage by selecting a different organic acid system only if it is outside the listed set. Phosphate buffer is explicitly called out for the most common inorganic buffering approach.
Optional preservative
Claim 20 adds an additional formulation feature:
- the solution further comprises an antimicrobial preservative
Scope implication: This claim is not needed for base infringement, but it can strengthen coverage against formulations that include preservative systems.
How strong is enforceable coverage against alternative formulations?
The claim strategy is compositionally constraining in four places. To avoid infringement, a product must usually break at least one element:
- Active concentration: Claim 1 requires 10 mg/mL lisdexamfetamine dimesylate.
- Formulations at different strengths are outside Claim 1, unless a different claim (not provided here) exists in the patent record covering other concentrations.
- pH window: Claim 1 requires pH 6.0 to 9.0, with dependent tightening to 6.0-8.5 and 6.5-8.0.
- A design-around could target pH outside these windows, but solubility/stability constraints often drive products back into these typical oral-buffer ranges.
- Cosolvent type: Claim 1 requires a glycol cosolvent.
- Replacing glycols with non-glycol solubilizers (for example, certain surfactants or non-glycol solvents) would be a clear path out of Claim 1 if the alternative does not fall under “glycol.”
- Buffer/cosolvent carrier: the carrier must have buffer and cosolvent within an aqueous system.
Because the claim set contains multiple overlapping dependent ranges (pH, cosolvent concentration), the patent can be asserted with a “match on the closest embodiment” even if the exact claimed broad parameters are not met perfectly, as long as the asserted dependent claim elements align.
Claim chart logic (what a litigant must prove)
Below is an infringement-style checklist mapping each essential feature.
| Claim element |
What it requires |
Where the scope tightens |
| Dosage form |
Oral pharmaceutical solution |
All claims |
| Active |
Lisdexamfetamine dimesylate at 10 mg/mL |
All claims |
| Carrier |
Pharmaceutically acceptable aqueous carrier |
All claims |
| System components |
Buffer + cosolvent |
All claims |
| pH |
6.0 to 9.0 |
Claim 7: 6.0-8.5; Claim 8: 6.5-8.0 |
| Cosolvent family |
Glycol |
Claim 2: propylene glycol and/or low molecular weight PEG; Claim 10: add glycerol/sorbitol/xylitol |
| Cosolvent identity specifics |
Propylene glycol and/or low molecular weight PEG |
Claim 2, 3, 9, 11, 12 |
| Cosolvent concentration |
5-300 mg/mL |
Claim 5: 50-250 mg/mL; Claim 6: 100-200 mg/mL |
| Buffer chemistry |
Listed organic/inorganic salts/acids |
Claim 14, 16, 18; phosphate buffer: Claim 15, 17, 19 |
| Preservative |
Antimicrobial preservative |
Claim 20 |
What does this mean for the patent landscape (practical competitive mapping)?
1) The patent covers formulation mechanics, not dosage-regimen claims
The claims are directed to a specific solution composition (strength, pH, cosolvent/buffer system). This pattern typically implies that adjacent competitive products can avoid literal infringement by changing at least one of the fixed parameters:
- concentration of lisdexamfetamine dimesylate (not 10 mg/mL),
- pH outside 6.0-9.0 (or outside dependent subranges),
- use of non-glycol cosolvent systems,
- use of buffer components outside the enumerated lists (though phosphate is explicitly covered).
2) The “glycol cosolvent” and “pH window” are the most design-around sensitive hooks
In practice, competitors often select cosolvent systems to hit solubility and viscosity targets while maintaining manufacturability. Because Claim 1 requires a glycol cosolvent and Claim 2 lists propylene glycol and low molecular weight PEG, solutions using those excipients inside the pH window are most exposed.
3) The buffer list is broad enough to capture common acid-salt and phosphate systems
Claim 14’s buffer set includes multiple common buffering pairs (citrate, acetate, phosphate) and several acids. Claim 15 explicitly captures phosphate buffer solutions. That coverage reduces the ability to “swap” buffer systems unless the alternative falls outside the enumerated set.
4) Overlapping dependent ranges increase likelihood of matching commercial targets
Multiple dependent claims cover:
- pH narrowing (6.0-8.5; 6.5-8.0),
- cosolvent ranges (5-300; 50-250; 100-200 mg/mL),
- cosolvent identity variants (propylene glycol vs low molecular weight PEG; plus optional polyols).
This increases enforceability in settlement posture because a formulation developer often lands in one of these practical operating bands.
Landscape summary: coverage breadth vs. constraint
Where this patent is broad
- Broad independent coverage: 10 mg/mL lisdexamfetamine dimesylate oral solution with buffer + glycol cosolvent at pH 6.0-9.0.
Where this patent is constrained
- Fixed active concentration: 10 mg/mL is required.
- Specific formulation architecture: must be an aqueous buffered system with a glycol cosolvent.
- pH must be in a defined window.
- Buffer components must include members of the enumerated set for dependent buffer claims.
- Enforceable dependent claim options narrow but provide multiple matching “hooks.”
What you can infer about claim hierarchy and enforceability posture
- Claim 1 is the primary infringement target for any product that matches the full core configuration.
- Claims 2, 4-6, 7-8, 9-13 are likely the “most assertable” dependent claims because they correspond to common formulation levers: pH, cosolvent identity, cosolvent loading, and polyol additions.
- Claims 14-19 offer alternative footholds based on buffer selection, especially phosphate buffer.
- Claim 20 can be used to strengthen coverage if a competitor includes preservative.
Key Takeaways
- Patent scope centers on a specific formulation: oral lisdexamfetamine dimesylate at 10 mg/mL in an aqueous buffer + glycol cosolvent system at pH 6.0-9.0.
- Design-around leverage is limited by three hard constraints: 10 mg/mL, pH window, and glycol cosolvent requirement in Claim 1.
- Dependent claims create multiple enforcement entry points through overlapping pH ranges, cosolvent identity (propylene glycol and low molecular weight PEG), cosolvent concentration bands, enumerated buffer chemistries, and optional preservatives.
- The most commercially exposed products are those that use propylene glycol and/or low molecular weight PEG with buffered pH in 6.0-9.0, especially within 50-250 mg/mL or 100-200 mg/mL cosolvent loadings.
FAQs
1) What composition does Claim 1 require, in one line?
An oral aqueous solution containing 10 mg/mL lisdexamfetamine dimesylate, a buffer plus a glycol cosolvent, with pH 6.0 to 9.0.
2) If a product uses a glycol cosolvent but has pH 9.2, is it covered by Claim 1?
No, because Claim 1 limits pH to 6.0 to 9.0.
3) If a competitor uses propylene glycol, does that automatically infringe?
Not automatically. It still must match the full Claim 1 requirements: 10 mg/mL active, buffered aqueous carrier, glycol cosolvent presence, and pH 6.0-9.0.
4) Which dependent claims are most relevant to formulation “tuning”?
Claims tied to pH (Claims 7-8) and cosolvent concentration (Claims 4-6) and cosolvent identity (Claims 2, 9, 11-13).
5) Does buffer selection matter only in the dependent buffer claims?
Buffer selection becomes central in the dependent claims that enumerate specific buffer components (Claims 14-19), while Claim 1 already requires a buffer generically.
References
[1] United States Patent 12,582,620 (claims provided in prompt).
