US Patent 7,655,636: How Narrow Are the Claims and What Matters in the U.S. Landscape?

United States Patent 7,655,636 claims a specific IV dosing method for coronary vasodilation intended to yield high coronary peak flow velocity with “little peripheral vasodilation,” using regadenoson and pharmaceutical excipients. The claim set is tightly structured around (1) route and dosing pattern (single IV bolus), (2) a measurable hemodynamic endpoint (coronary peak flow velocity increase), and (3) optional myocardial perfusion imaging with radionuclide timing and sequencing.

The practical scope is narrower than regadenoson marketing claims that broadly cover vasodilation or myocardial perfusion imaging, because here the enforceable method boundaries hinge on a single bolus and a quantitative velocity threshold.

What Exactly Do the Claims Cover? (Core Method Scope)

Claim 1 is the anchor

Claim 1 defines the method in one sentence and includes all operative limitations:

What you do: “A method of producing coronary vasodilation with little peripheral vasodilation”
Who receives it: “administering to a human”
Route and dosing pattern: “a single intravenous (IV) bolus dose”
What you administer: “a pharmaceutical composition comprising regadenoson”
- Regadenoson is identified by chemical name and formula (as provided in the claim text).
What else is required: “at least one pharmaceutical excipient” in an amount sufficient to increase performance.
Performance metric (hard threshold):
- “increase the average coronary peak flow velocity by at least about 16.5 cm/sec.”

Enforcement consequence: Any U.S. method practice that uses regadenoson but does not satisfy both (a) the single IV bolus dosing pattern and (b) the coronary peak flow velocity increase threshold (average, at least ~16.5 cm/sec), sits outside Claim 1’s strictest literal scope.

Claims 2-5 narrow dosing rate and dose amount

These claims further limit Claim 1 by specifying administration duration and dose quantity:

Claim 2: administer the single dose in about 10 to about 20 seconds.
Claim 3: dose is sufficient to raise average coronary peak flow velocity by about 16.5 to about 77.0 cm/sec.
Claim 4: single dose includes about 10 to about 500 micrograms of regadenoson.
Claim 5: single dose is about 0.05 to about 60 μg/kg.

Enforcement consequence: These are dosing-range and kinetics limitations. They matter because regadenoson has multiple clinical regimens in the market history; if an accused method uses different injection duration, different bolus structure, or different dosing ranges, it can avoid dependent-claim requirements even if it still produces coronary vasodilation.

Claims 6-10 add an imaging pathway

Claims 6-10 introduce myocardial perfusion imaging and radionuclide administration timing/sequencing:

Claim 6: myocardial perfusion imaging is performed after the single regadenoson bolus.
Claim 7: radionuclide is administered at a time selected from:
- before the regadenoson dose,
- simultaneously,
- after.
Claim 8: radionuclide and regadenoson administered separately.
Claim 9: radionuclide and regadenoson administered simultaneously.
Claim 10: myocardium examination begins no sooner than about 1 minute from regadenoson administration.

Enforcement consequence: Imaging implementations are captured, but with timing windows. The claim set is written to cover multiple radionuclide workflows (separate vs simultaneous), so a design-around is more likely to depend on timing (especially Claim 10’s “no sooner than 1 minute”) or on not using the single-bolus regadenoson regimen as defined.

How Broad Is This Compared with Regadenoson’s General Indications?

Breadth inside the claim set

Within the defined regimen, Claim 1 is conceptually broad in that it covers:

any human receiving regadenoson by the specified method,
any “pharmaceutical composition” with excipients sufficient to meet the velocity threshold,
and a quantitative endpoint.

Breadth limited by exact method and endpoint

The claims do not cover:

continuous infusion regimens,
multi-bolus titration,
routes other than single IV bolus,
or outcomes not tied to the specified coronary peak flow velocity threshold.

In practice, this claim style targets a procedure standardization use-case: a reproducible hemodynamic outcome (coronary peak flow velocity increase) with a safety/side-effect framing (“little peripheral vasodilation”), though the enforceable part is the velocity metric.

Where “Little Peripheral Vasodilation” Lands Legally

The phrase “with little peripheral vasodilation” is in Claim 1’s preamble-style functional limitation. In method claims like this, it can still act as a substantive requirement in claim construction because it is tied to the method’s purpose. However, the only explicit numeric endpoint in Claim 1 is the coronary peak flow velocity threshold.

Net claim land:

The strongest measurable limitation is coronary peak flow velocity increase ≥ about 16.5 cm/sec.
The “little peripheral vasodilation” concept is likely to be argued as either:
- a functional requirement implied by the dosing formulation and bolus conditions, or
- a statement of intended benefit that is not a distinct measurable step.

Either way, in an infringement analysis, the velocity endpoint will dominate because the claim is written with a numeric threshold.

Design-Around Pressure Points (U.S. Method Infringement)

The enforceable boundaries suggest four primary non-infringement levers:

Bolus structure: not a “single IV bolus dose.”
Dose timing: not injected over “about 10 to about 20 seconds” (Claim 2).
Dose amount or weight range: not within the microgram or μg/kg limits (Claims 4-5).
Hemodynamic endpoint: not achieving average coronary peak flow velocity increase in the claimed ranges (Claims 1 and 3).
Imaging timing: myocardium examination begins before about 1 minute post-dose (Claim 10).

Because Claims 7-9 cover radionuclide sequencing options, radionuclide workflow changes alone are unlikely to avoid infringement if all other limitations are met.

Claim Chart Style Decomposition (What Has to Be Present)

Below is a mapping of claim elements to likely practice components.

Claim Element	Literal Requirement in the Claim	Likely Corresponding Practice Component
Method objective	coronary vasodilation with little peripheral vasodilation	selected clinical goal, supported by measured outcomes
Subject	human	patient population
Regimen structure	single IV bolus dose	injection technique and administration protocol
Active	regadenoson	drug identity
Composition	excipients included	formulation includes pharmaceutical excipients
Performance metric	increase average coronary peak flow velocity ≥ about 16.5 cm/sec	catheter-based or other coronary flow velocity measurement protocol
Injection duration	10 to 20 seconds (Claim 2)	pump rate / manual timing / infusion protocol
Dose amount	10 to 500 micrograms (Claim 4)	total administered regadenoson mass
Dose by weight	0.05 to 60 μg/kg (Claim 5)	weight-based dosing
Perfusion imaging	myocardial perfusion imaging after dosing (Claim 6)	imaging sequence
Radionuclide timing	before, simultaneous, or after (Claim 7)	radionuclide administration schedule
Separate vs simultaneous	separately (Claim 8) or simultaneously (Claim 9)	scheduling differences
Imaging start time	examination begins no sooner than ~1 minute (Claim 10)	imaging commencement timing

Scope Summary: What Regimen Type Is Captured

Captured: a standardized regadenoson coronary-vasodilation protocol using single IV bolus, administered over a defined time window (10-20 seconds), with dosing quantities within specified ranges, designed to produce a quantified coronary hemodynamic response (peak flow velocity increase), and optionally paired with myocardial perfusion imaging with radionuclide timing and a minimum imaging start time.

Not clearly captured: regimens that change route, split dosing, dosing duration, dose mass/weight ranges, or that do not meet the coronary velocity endpoint.

Patent Landscape Implications in the U.S. (Strategic View)

How this patent fits the enforcement ecosystem

For U.S. regadenoson strategy, patents typically cluster into:

compound (drug substance) protection (chemical identity),
formulation (specific compositions),
method of use (clinical protocols, endpoints, imaging workflows),
device/process (if any).

US 7,655,636 is a method-of-use claim set, specifically tethered to:

a hemodynamic endpoint (“average coronary peak flow velocity”),
a dosing modality (single IV bolus),
and imaging timing (optional, dependent claims).

That means it is most relevant for challengers and competitors not trying to replace regadenoson itself, but trying to modify administration parameters and imaging workflow to avoid an asserted method.

Practical litigation posture

In enforcement:

Plaintiff’s strongest case is usually procedural method infringement with evidence from clinical protocol documentation and measured hemodynamic outcomes.
Defense often targets:
- injection protocol deviations (seconds, bolus structure),
- dosing quantities and whether they fall within claimed ranges for a specific patient,
- and failure to show average coronary peak flow velocity increase as claimed.

Frequent market reality

Even when competitors do not change the active drug, they can often alter:

injection duration,
bolus vs infusion structure,
imaging start timing, to reduce risk against narrowly drafted method claims.

This patent’s tight quantitative limitations make it particularly sensitive to protocol differences.

Key Takeaways

US 7,655,636 is a narrowly drafted method-of-use patent centered on a single IV bolus of regadenoson with a hard numeric hemodynamic endpoint: average coronary peak flow velocity increase ≥ about 16.5 cm/sec (Claim 1).
Dependent claims tighten the regimen with injection duration (10-20 seconds), dose amount ranges (10-500 micrograms), weight-based ranges (0.05-60 μg/kg), and upper endpoint cap (16.5-77.0 cm/sec) (Claims 2-5).
Imaging claims (6-10) broaden applicability to myocardial perfusion imaging but still hinge on timing, especially no earlier than ~1 minute for myocardium examination start (Claim 10).
The most viable non-infringement strategies are protocol changes that break one of the anchor limitations: single bolus, injection duration, dose quantity, endpoint attainment, or imaging start timing.

FAQs

1. What is the single most important limitation in Claim 1?
The method requires a single IV bolus of a regadenoson pharmaceutical composition that increases average coronary peak flow velocity by at least about 16.5 cm/sec.

2. Do the claims require a specific radionuclide?
The claims require a radionuclide for myocardial perfusion imaging timing, but they do not specify a radionuclide identity in the text provided; the timing and sequencing are the operative elements (Claims 6-10).

3. Can a competitor avoid infringement by using regadenoson but changing injection duration?
Yes, Claim 2 limits administration to about 10 to about 20 seconds; changing injection duration is a direct route to avoiding dependent-claim coverage if Claim 1 is otherwise implicated.

4. Is “little peripheral vasodilation” quantified in these claims?
No explicit numeric peripheral metric is provided in the claim text given; the only explicit quantitative metric is the coronary peak flow velocity endpoint (Claims 1 and 3).

5. Does the patent cover myocardial perfusion imaging protocols?
Yes, but only in the context of the claimed regadenoson single IV bolus regimen followed by imaging, with radionuclide timing options and a minimum imaging start time (Claims 6-10).

References

[1] United States Patent 7,655,636.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2005295437	⤷ Start Trial
Canada	2583185	⤷ Start Trial
China	101076343	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 7,655,636

Summary for Patent: 7,655,636