United States Patent 9,028,868: What Is Claimed, How Broad the Scope Is, and Where It Sits in the Landscape
US 9,028,868 claims methods of treating stimulant-responsive conditions by oral dosing of amphetamine (or salts/prodrugs) using a single oral delayed-release format that creates a specific exposure profile: a long lag period with low early plasma levels, a constrained early-to-total exposure ratio, and a delayed Tmax window.
What core dosing format defines the claim scope?
The independent claim elements in Claim 1 (method claim) and the second independent cluster in Claim 6 (solid composition method claim) converge on the same architecture and exposure targets:
Single-dose, multilayer release architecture
The claimed composition is an oral delayed release dosage comprising:
- Core: therapeutic amount of a central nervous system stimulant (amphetamines) + at least one pharmaceutically acceptable excipient
- Sustained release layer coating the core
- Delayed release layer coating the sustained release layer
Exposure profile constraints (the legal “meat”)
The delayed release layer must produce all of the following after oral administration:
- Lag period ≥ 5 hours during which plasma concentration is < 10% of Cmax
- AUC0-10 < ~7% of AUC0-48
- Tmax between 12 and 19 hours
In Claim 1 the constraints are tied to “the amphetamine, amphetamine salt, amphetamine prodrug, or combination thereof” within the single delayed release dosage.
Claim 6 uses closely aligned clinical shorthand for the same profile (see below).
Human-dosing equivalent language
Claim 6 recasts the exposure profile in human terms:
- No more than ~10% of Cmax is detectable at 5 hours
- AUC0-10 < ~7% of AUC0-48
- Tmax between 12 and 19 hours
So, whether the infringement theory is aimed at a process method (Claim 1) or a composition method (Claim 6), the exposure profile is the same gating metric.
Which drug substances are in the claim scope?
The stimulant identity is an explicit limitation.
Amphetamine families expressly listed
Claim 1 covers administration of:
- Amphetamine
- An amphetamine salt
- An amphetamine prodrug
- A combination
Claim 3 narrows this by listing examples:
- amphetamine / pharmaceutical amphetamine salt
- dextroamphetamine / pharmaceutical salt
- lisdexamfetamine dimesylate (prodrug) / pharmaceutical salt
Claims 8 to 11 further enumerate within the Claim 6 composition method:
- Claim 8: “amphetamine, dextroamphetamine, or an isomer, racemic mixture, prodrug or pharmaceutical salt of any thereof”
- Claim 9: amphetamine or salt
- Claim 10: dextroamphetamine or salt
- Claim 11: lisdexamfetamine dimesylate or salt
Implication for scope: The patent does not read only on lisdexamfetamine. It reads on amphetamine-class actives that can be delivered in a multilayer oral delayed-release format that produces the specific exposure profile.
Which clinical indications are covered?
Claim 5 lists conditions responsive to CNS stimulants and ties them to the method claims.
Covered conditions include:
- attention deficit disorder (ADD)
- attention deficit hyperactivity disorder (ADHD)
- excessive daytime sleepiness
- major depressive disorder
- bipolar depression
- negative symptoms in schizophrenia
- chronic fatigue
- fatigue associated with chemotherapy
- binge eating disorder
Claim 13 narrows further in a dependent claim to:
This provides a clear “core” commercial target (ADHD/ADD) while also retaining secondary label expansion pathways (sleepiness, fatigue, certain depressive symptom domains, binge eating).
How broadly does timing and dose constrain infringement?
Dosing frequency
Claim 2 adds:
- once a day (dependent limitation)
That means some formulations or regimens that meet the exposure profile but require non-once-daily dosing sit outside Claim 2 (but can still fall under Claim 1/6 if those independent claims are satisfied).
Dose range
Claim 12 states:
Claim 14 mirrors it for the narrowed ADHD/ADD dependent path:
- effective amount 5 mg to 54 mg
Tmax anchoring
Claim 4 states:
This tightens the timing in a dependent claim. Under Claim 1/6, Tmax is already constrained to 12 to 19 hours; Claim 4 further selects a subset of that range.
What does the claim set suggest about the intended product and design space?
The combination of:
- a multilayer delayed release over a sustained release core, and
- specific pharmacokinetic thresholds:
- early plasma suppressed relative to Cmax
- low early AUC fraction
- long-lag, delayed Tmax
maps to a delayed-onset once-daily amphetamine exposure profile rather than immediate-release or conventional extended-release.
From a design-around perspective, the claims are not limited to a specific polymer system or manufacturing process in the text you provided. They are functionally constrained through PK metrics and layered architecture. That generally:
- increases the chance that different formulations can infringe if they hit the same PK targets, and
- increases the chance that a design-around must shift exposure timing or early suppression beyond those thresholds.
Where does US 9,028,868 likely sit in the stimulant “delayed onset” landscape?
Positioning relative to known delayed-onset amphetamine products
The lisdexamfetamine class is a prodrug approach to delayed conversion to active dextroamphetamine. However, the claims in 9,028,868 also require a delayed release layer over a sustained release layer, which implies the patent is not relying only on metabolic conversion timing. It requires physical dosage form release behavior producing low early plasma and late Tmax.
Practical take: the patent is best read as claiming a specific oral dosage-form mechanism that yields a delayed exposure profile, using amphetamine actives and prodrugs as payloads.
Competitive moat shape
Because key limits are PK thresholds:
- “lag period ≥ 5 hours with plasma <10% of Cmax”
- “AUC0-10 < ~7% of AUC0-48”
- “Tmax 12 to 19 hours”
competitors cannot “avoid” infringement by swapping excipients alone if the exposure profile still matches. They would need to change the time course of plasma exposure outside the claimed windows, or remove the layer architecture (core + sustained release layer + delayed release layer), depending on how strictly those structural elements are construed.
Claim-by-claim scope map (what must be present for coverage)
Independent claim 1 (method)
Coverage requires:
- Treat condition responsive to CNS stimulant
- Orally administer effective amount of amphetamine/salt/prodrug
- In a single delayed release dosage with:
- core: amphetamine + excipients
- sustained release layer over core
- delayed release layer over sustained release layer
- PK requirements:
- lag period ≥ 5 hours with plasma <10% Cmax
- AUC0-10 < ~7% of AUC0-48
- Tmax 12 to 19 hours
Dependent claims linked to use conditions
- Claim 2: once daily
- Claim 3: specifies example actives (amphetamine/dextroamphetamine/lisdexamfetamine dimesylate) or salts
- Claim 4: Tmax subset (Cmax >15 hours)
- Claim 5: list of conditions
Independent claim 6 (composition method)
Coverage requires:
- Orally administer to a human a solid oral pharmaceutical composition with:
- core + sustained release layer + delayed release layer (same architecture)
- PK human thresholds:
- ≤10% Cmax detectable at 5 hours
- AUC0-10 < ~7% AUC0-48
- Tmax 12 to 19 hours
Dependent claims 7 to 14
- Claim 7: condition list
- Claim 8-11: stimulant identity variants (amphetamine/dextroamphetamine/prodrug/salts)
- Claim 12: dose 5-54 mg
- Claim 13: ADD/ADHD
- Claim 14: dose 5-54 mg for ADD/ADHD branch
Risk map for generic or competitor entry (functional infringement hotspots)
Most infringement-sensitive design variables
Based on the claim language, the highest-risk variables are those that directly affect the listed PK thresholds:
| Design variable |
Why it matters legally |
Likely effect on claim satisfaction |
| Release lag (time to early plasma) |
Claim demands ≥5-hour lag with plasma <10% of Cmax |
Changing lag below 5 hours can fall outside; increasing lag likely keeps risk high if Tmax remains in window |
| Early exposure fraction (AUC0-10 / AUC0-48) |
Claim demands AUC0-10 < ~7% |
A small formulation shift can push early AUC above threshold, creating design-around leverage |
| Tmax timing |
Claim requires 12 to 19 hours; dependent claim narrows >15 |
Changing retardation speed shifts Tmax and can defeat coverage |
| Layer architecture |
Core + sustained + delayed layers is explicitly claimed |
Omitting the delayed release layer or collapsing layer roles can avoid structural limitations |
Less determinative (within provided text)
- Excipients: only need to be “pharmaceutically acceptable”; the claim does not state specific excipient types
- Dose strength: constrained to 5-54 mg in dependent claim 12/14; independent claims still allow “effective amount” unless interpreted to require the same range
What do the claims imply about likely prosecution intent?
The layered architecture plus strict PK thresholds indicates the patentee pursued a dosage-form class definition rather than a narrow drug-only claim. The patent’s strength is that it:
- ties structure (core + sustained + delayed layers) to
- functional outcomes (late Tmax + suppressed early plasma and early AUC fraction).
For enforceability, that supports arguments that the “how” is controlled by the dosage form and measured by PK endpoints.
Key Takeaways
- US 9,028,868 is centered on oral amphetamine-class therapy delivered in a single delayed-release dosage with a core + sustained release layer + delayed release layer architecture.
- The claims are PK-gated: ≥5-hour lag with plasma <10% of Cmax, AUC0-10 < ~7% of AUC0-48, and Tmax 12 to 19 hours.
- Covered stimulants explicitly include amphetamine, dextroamphetamine, and lisdexamfetamine dimesylate, including salts and prodrug variants.
- Covered indications include a broad stimulant-responsive set, with dependent claims clearly anchoring ADD/ADHD.
- For market entrants, the biggest infringement levers are the early exposure fraction and Tmax window plus the presence of the claimed layer architecture.
FAQs
1) Does the patent claim only lisdexamfetamine (Vyvanse) formulations?
No. The claims include amphetamine, dextroamphetamine, and lisdexamfetamine dimesylate, along with salts and prodrug forms, as long as the dosage form delivers the claimed PK profile and has the claimed layered architecture.
2) What PK endpoints drive infringement risk?
The key endpoints are lag period ≥5 hours with plasma <10% of Cmax, AUC0-10 < ~7% of AUC0-48, and Tmax 12 to 19 hours (with a dependent narrowing to Cmax >15 hours).
3) Is the claim limited to once-daily dosing?
Only Claim 2 explicitly requires once a day. The independent claims are not limited to once daily based on the text provided; however, any actual regimen used must still satisfy the architecture and PK thresholds.
4) What dose range is explicitly covered?
Dependent Claim 12 limits effective amount to 5 mg to 54 mg. Independent claims use “effective amount,” while dependent claims provide the explicit numeric range.
5) Are the indications limited to ADHD/ADD?
No. While dependent claims focus on ADD/ADHD, the independent claim set includes a longer list: excessive daytime sleepiness, major depressive disorder, bipolar depression, negative symptoms in schizophrenia, chronic fatigue, chemotherapy-associated fatigue, and binge eating disorder.
References (APA)
[1] US Patent 9,028,868. Claims as provided in user prompt.
