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Clinical and Pharmacogenetic Study of Attention Deficit With Hyperactivity Disorder (ADHD)

This study is currently recruiting participants.
See Contacts and Locations
Verified August 2017 by Ridha Joober, McGill University
Information provided by (Responsible Party):
Ridha Joober, McGill University Identifier:
First received: June 4, 2007
Last updated: August 30, 2017
Last verified: August 2017
Attention deficit with hyperactivity disorder (ADHD) is a very common behavioral problem during childhood. It is estimated that up to 80% of this disorder could be related to genetic factors. The most common treatment for ADHD is psychostimulants. In this study, the researchers investigate the effect of genetic variants in increasing the risk for behaviours pertinent to ADHD or in modulating the response of these behaviours to methylphenidate. Response to methylphenidate is evaluated through a double blind placebo controlled one week study.

Condition Intervention Phase
Attention Deficit Hyperactivity Disorder Drug: Ritalin Drug: Placebo Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Clinical and Pharmacogenetic Study of Attention Deficit With Hyperactivity Disorder (ADHD)

Resource links provided by NLM:

Further study details as provided by Ridha Joober, McGill University:

Primary Outcome Measures:
  • Conners' Global Index - Parent Version (CGI-P) [ Time Frame: Once weekly during the medication trial ]
    10-item standardized scale evaluating ADHD symptoms; filled by parents.

  • Conner's Global Index - Teacher Version (CGI-T) [ Time Frame: Once weekly during the medication trial ]
    10-item standardized scale evaluating ADHD symptoms; filled by teachers.

Estimated Enrollment: 1000
Study Start Date: November 1999
Estimated Study Completion Date: March 2025
Estimated Primary Completion Date: September 2018 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: Ritalin Drug: Ritalin
0.25 mg/kg bid, orally for 7 consecutive days
Placebo Comparator: Placebo Drug: Placebo
taken orally twice a day for 7 consecutive days

Detailed Description:

Attention Deficit Hyperactivity disorder (ADHD) is a syndrome that is characterized by inattention, motor hyperactivity and impulsivity. It affects 8 to 12% of the population. The presentation of children with ADHD can be varied, from simple inattention to severe motor hyperactivity and impulsivity. It has a negative impact on the child's life, including poor school achievement and difficulty with peer and family relationships.

Although the etiology of ADHD is not well understood, genetic factors are known to play a significant role in the pathogenesis of ADHD, as indicated by family, twin and adoption studies. In addition, environmental factors such as smoking during pregnancy and obstetrical complications have been found to contribute significantly in increasing the risk for and severity of ADHD. It is therefore likely that genetic predisposing factors interact with environmental factors to produce the behavioral disturbances observed in ADHD. The first goal of this study is therefore to investigate possible genetic and environmental risk factors, and examine how they might interact to confer increased risk for ADHD.

A majority of children (70%) with ADHD show a significant improvement with of their behavioral disorder when treated with stimulant drugs such as methylphenidate (MPH). However, the extent to which each child benefits from MPH is variable and some of the children do not improve at all in spite of adequate trials with stimulant drugs. The second purpose of this project is to study the correlates/predictors of responsiveness to MPH in school-aged children and to identify genetic factors that may modulate the behavioral response to this drug.

In order to achieve our research goals, children with ADHD are invited to participate to a two-week double-blind placebo controlled medication trial with MPH (Ritalin, 0.5mg/kg/day). During these two weeks, neuropsychological and behavioral assessments of the child are performed at the clinic to evaluate the cognitive performance of the child while on medication and placebo. Parents are invited to answer questionnaires about the behavior of their child and about family history of mental disorders, as well as prenatal and perinatal risk factors. Finally, the participating child, both parents, and siblings are invited to provide a blood or saliva sample for genetic analysis.


Ages Eligible for Study:   6 Years to 12 Years   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • ADHD

Exclusion Criteria:

  • Psychosis
  • Tourette syndrome
  • Intelligence quotient (IQ) < 70
  • Pervasive developmental disorder (PDD)
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00483106

Contact: Johanne Bellingham, RA (514) 761-6131 ext 2098

Canada, Quebec
Douglas Mental Health University Institute Recruiting
Montreal, Quebec, Canada, H4H 1R3
Contact: Johanne Bellingham, RA    (514) 761-6131 ext 2098   
Sponsors and Collaborators
McGill University
Principal Investigator: Ridha Joober, MD, PhD Douglas Mental Health University Institute
Principal Investigator: Natalie Grizenko, MD, FRCPC Douglas Mental Health University Institute
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Ridha Joober, Md, PhD., McGill University Identifier: NCT00483106     History of Changes
Other Study ID Numbers: 99-22
Study First Received: June 4, 2007
Last Updated: August 30, 2017

Keywords provided by Ridha Joober, McGill University:
Attention Deficit Hyperactivity Disorder

Additional relevant MeSH terms:
Attention Deficit and Disruptive Behavior Disorders
Attention Deficit Disorder with Hyperactivity
Pathologic Processes
Neurodevelopmental Disorders
Mental Disorders
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms
Central Nervous System Stimulants
Physiological Effects of Drugs
Dopamine Uptake Inhibitors
Neurotransmitter Uptake Inhibitors
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Dopamine Agents
Neurotransmitter Agents processed this record on September 20, 2017