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CompletedNCT01904526Updated Mar 6, 2020Results posted

PK/PD Comparison of Guanfacine ER and IR

A Phase 2 interventional study of Guanfacine in Smoking, sponsored by Yale University. Completed at 1 site in United States. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2020-03-06.

Sponsored by Yale University · Phase 2, Interventional, and Other

Phase
Phase 2
Study type
Interventional
Enrollment
5
Allocation
Not applicable
Ages
18 Years to 65 Years
Sex
All
01

Study summary

Evaluate whether a 4mg/day or 6/mg day dose of extended-release guanfacine produces pharmacokinetic/dynamic (PK/PD) properties similar to 3mg/day immediate release guanfacine.

02

Conditions studied

  • Smoking

Keywords

  • Guanfacine
  • PK/PD
  • Smokers
03

In context

Lead sponsor

Yale University is the lead sponsor of 1,724 studies on the registry; 298 are open to participants now.

Of its 210 completed or terminated interventional studies of FDA-regulated products, 126 (60%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Age 18-65
  • Able to read, write and comprehend English
  • Smoker
  • Able to take oral medications and willing to adhere to medication regimen
  • Provide evidence of a stable living residence in the last 2 months, have reasonable transportation to the study site, and have no plans to move within the next 3 months or unresolved legal problems.

Exclusion criteria

Exclusion Criteria:

  • Any significant current medical conditions that would contraindicate smoking
  • Current Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) abuse or dependence of other substances, other than nicotine dependence or alcohol abuse
  • Positive test results at intake appointment on urine drug screens for illicit drugs
  • Past 30 day use of psychoactive drugs including anxiolytics and antidepressants
  • Women who are pregnant or nursing
  • Suicidal, homicidal or evidence of current mental illness such as schizophrenia, bipolar disorder or major depression, or anxiety disorders
  • Meeting DSM-IV criteria for current attention deficit hyperactivity disorder (ADHD)
  • Individuals who are currently taking medications known to be effective for smoking cessation or are regular users of other tobacco products in the past 30 days
  • Only one member per household can participate in the study

  • Specific exclusions for administration of guanfacine not already specified include:

    • EKG evidence at baseline screening of any clinically significant conduction abnormalities or arrhythmias
    • Known intolerance for guanfacine or any alpha blocker
    • History of fainting, syncopal attacks
    • Heart failure or myocardial infarction
    • Impaired liver (as indicated by aspartate aminotransferase (AST), alanine aminotransferase (ALT) >3x normal)
    • Renal function (as indicated by estimated creatinine clearance \<60cc/min)
    • Treatment with any antihypertensive drug or any alpha-adrenergic blocker
    • Use of any central nervous system depressant (e.g., phenothiazines, barbiturates, benzodiazepines)
    • Use of strong cytochrome P450 3A4 (CYP3A4) inhibitors (e.g., ketoconazole) or inducers (e.g., rifampin), or consumption of grapefruit juice
  • Subjects may have not donated blood in the past 8 weeks or have been involved in other investigational studies that involve substantial blood draws or medications unknown to us
05

Study design

Phase
Phase 2
Primary purpose
Other
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
5 participants (actual)

Study arms

  • Experimental
    Guanfacine

    Guanfacine 3 mg/day immediate release followed by Guanfacine 4mg/day extended release followed by Guanfacine 6 mg/day extended release

    Drug: Guanfacine

Interventions

  • DrugGuanfacine

    3mg/day IR with 3-week lead-in period. Maintained at steady state to complete lab session. After completion of lab session, 1-week lead-in medication period to 4mg/day ER. Maintained at steady state to complete lab session. After completion of lab session, 1-week lead-in medication period to 6mg/day ER. Maintained at steady state to complete lab session. 5-day taper after lab.

    Also known as: Tenex, Intuniv

06

What researchers measure

Primary outcomes

  1. Plasma Trough Levels of Guanfacine

    Evaluate whether a 4mg/day or 6mg/day dose of extended-release guanfacine produces pharmacokinetic (PK) properties similar to 3mg/day immediate release guanfacine by measuring plasma trough levels of guanfacine for each dose

    Time frame: +24 hours on Lab Session days (Days 22, 49, 58)

Secondary outcomes

  1. Heart Rate

    Evaluate the safety and tolerability of guanfacine by measuring physiologic reactivity (e.g., heart rate)

    Time frame: Last day of titration period 1 (Day 21) to the last day of titration period 3 (Day 57)

  2. Systolic Blood Pressure

    Evaluate the safety and tolerability of guanfacine by measuring physiologic reactivity (e.g., systolic blood pressure)

    Time frame: Last day of titration period 1 (Day 21) to the last day of titration period 3 (Day 57)

07

Results

Posted Apr 23, 2018

Participant flow

Participant flow — Overall Study
MilestoneGuanfacine
Started5
Completed5
Not completed0

Outcome measures

PrimaryPlasma Trough Levels of Guanfacine

Evaluate whether a 4mg/day or 6mg/day dose of extended-release guanfacine produces pharmacokinetic (PK) properties similar to 3mg/day immediate release guanfacine by measuring plasma trough levels of guanfacine for each dose

Time frame:
+24 hours on Lab Session days (Days 22, 49, 58)
Reported as:
Mean · ng/ml
Plasma Trough Levels of Guanfacine
ng/mlGuanfacine 3mg/Day Immediate ReleaseGuanfacine 4mg/Day Extended ReleaseGuanfacine 6mg/Day Extended Release
Plasma Trough Levels of Guanfacine3.40 ± 0.333.46 ± 0.675.92 ± 1.02
SecondaryHeart Rate

Evaluate the safety and tolerability of guanfacine by measuring physiologic reactivity (e.g., heart rate)

Time frame:
Last day of titration period 1 (Day 21) to the last day of titration period 3 (Day 57)
Reported as:
Mean · beats per minute
Heart Rate
beats per minuteGuanfacine 3mg/Day Immediate ReleaseGuanfacine 4mg/Day Extended ReleaseGuanfacine 6mg/Day Extended Release
Heart Rate59.6 ± 1.7558.8 ± 3.9761.6 ± 5.30
SecondarySystolic Blood Pressure

Evaluate the safety and tolerability of guanfacine by measuring physiologic reactivity (e.g., systolic blood pressure)

Time frame:
Last day of titration period 1 (Day 21) to the last day of titration period 3 (Day 57)
Reported as:
Mean · mmHg
Systolic Blood Pressure
mmHgGuanfacine 3mg/Day Immediate ReleaseGuanfacine 4mg/Day Extended ReleaseGuanfacine 6mg/Day Extended Release
Systolic Blood Pressure101.0 ± 3.73107.4 ± 7.51108.4 ± 7.16

Adverse events

Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Guanfacine 3mg/Day Immediate Release0/5 (0%)0/5 (0%)3/5 (60%)
Guanfacine 4mg/Day Extended Release0/5 (0%)0/5 (0%)4/5 (80%)
Guanfacine 6mg/Day Extended Release0/5 (0%)0/5 (0%)4/5 (80%)
Most frequent other events
Showing 10 of 28
Most frequent other events
EventGuanfacine 3mg/Day Immediate ReleaseGuanfacine 4mg/Day Extended ReleaseGuanfacine 6mg/Day Extended Release
Dry mouthGeneral disorders2/54/54/5
DrowsinessGeneral disorders3/53/53/5
FatigueGeneral disorders3/53/53/5
Gas painsGastrointestinal disorders2/52/53/5
DizzinessGeneral disorders2/52/52/5
ConstipationGastrointestinal disorders2/52/52/5
HeadacheGeneral disorders2/51/50/5
WeaknessGeneral disorders1/50/52/5
ImpotenceGeneral disorders2/50/51/5
InsomniaGeneral disorders0/51/50/5

Baseline characteristics

Age, Continuous
Age, Continuous(Years)Guanfacine
Mean45.8 ± 2.49
Sex: Female, Male
Sex: Female, Male(Participants)Guanfacine
Female2
Male3
08

Study locations

1 site
  • Yale Center for Clinical Investigations, Yale University
    New Haven, Connecticut 06519, United States
09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 6, 2020, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT01904526
Lead sponsor
Yale University
Collaborators
National Institute on Drug Abuse (NIDA)
Responsible party
Sherry McKee (Associate Professor of Psychiatry, Yale University) — Principal investigator
First posted
Jul 22, 2013
Start date
Jul 2013
Primary completion
Dec 2016
Completion
Dec 2016
Results posted
Apr 23, 2018
Last update
Mar 6, 2020

Study contacts

Sherry A McKee, PhD
principal investigator · Yale University

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Mar 2020. You cannot join it, but the record below documents what was studied.

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