Experimental fMRI Study of Guanfacine and Lisdexamfetamine in ADHD Adolescents

    Not Recruiting
  • days left to enroll
  • participants needed
  • sponsor
    King's College London
Updated on 19 August 2022
functional magnetic resonance imaging
cns stimulants


This is not a clinical trial. The aim of this study is to understand the mechanism of action of two recently licensed drugs for ADHD on brain function. We will compare the brain activation changes elicited by Guanfacine extended release (GXR; a non-stimulant drug) with the brain activation changes elicited by Lisdexamfetamine (LISDEX; a stimulant drug) and by placebo in 20 drug-free patients with ADHD using functional Magnetic Resonance Imaging (fMRI). For this purpose we intend to scan participants during their performance of tasks of attention, working memory, and inhibition, which we know from previous studies to elicit abnormal brain activation patterns in ADHD patients (Rubia et al., 2005; Smith et al., 2006).


Twenty ADHD patients between 8 and 20 years of age will participate in the double-blind, randomised, active drug condition, within-group, placebo-controlled experimental fMRI study. Each participant will be assessed in baseline measures during a pre-assessment visit. Then the patient will be scanned 3 times under each of these 3 drug conditions: GXR, LISDEX, and placebo. Every patient will receive a single typical clinical weight-adjusted dose of GXR (0.05mg/kg rounded down to the closest dose of 1mg, 2mg, or a maximum of 3mg), LISDEX (for participants aged 8-9 years 20mg regardless of weight; for participants aged 10-20 years the dose will be calculated at 0.5mg/kg rounded to the closest 30, 40, or 50mg, middle doses, e.g. 35mg, will be rounded down) and placebo (10mg Vit C) in one of the scans, in a randomised order. Patients will perform a battery of cognitive tests 3.5 hours after drug administration, after which the will undergo an fMRI scan. The scan will start 4.5 hours after drug administration where drugs have shown to have maximum plasma concentration. Participants will be scanned 3 times, one week apart, under each drug condition.

Condition Attention deficit hyperactivity disorder, Attention Deficit/Hyperactivity Disorder (ADHD - Pediatric), Attention Deficit/Hyperactivity Disorder (ADHD - Adults), Family Medicine-ADHD Pediatrics, Attention Deficit/Hyperactivity Disorder (ADHD - Adults), Attention Deficit/Hyperactivity Disorder (ADHD - Pediatric), Family Medicine-ADHD Pediatrics, adhd
Treatment Placebo, Lisdexamfetamine dimesylate, Guanfacine Extended Release Oral Tablet
Clinical Study IdentifierNCT03333668
SponsorKing's College London
Last Modified on19 August 2022

Similar trials to consider


Browse trials for

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note