Memantine for Executive Dysfunction in Adults With ADHD: A Pilot Study

Not Applicable

Completed

Conditions: Attention Deficit Hyperactivity Disorder (ADHD)
Executive Function Deficits (EFD)

Interventions: Drug: Placebo
Drug: Memantine Hydrochloride
Drug: OROS-Methylphenidate

Brief Summary: This is a 12-week clinical trial evaluating the efficacy and safety of memantine hydrochloride (Namenda) in the treatment of executive function deficits (EFDs) in adults with Attention Deficit Hyperactivity Disorder (ADHD) receiving open-label treatment with OROS-Methylphenidate (OROS-MPH, Concerta). The study aims to examine the effects of treatment with memantine on ADHD symptoms. Following screening procedures, memantine is prescribed in randomized, double-blind fashion (equal chance of medication or placebo) for 12 weeks, along with open-label OROS-MPH (everyone receives medication).

Recruitment & Eligibility

Inclusion Criteria

Male or female adults ages 18-50 years
A diagnosis of childhood onset ADHD, according to the Diagnostic and Statistical Manual of Mental Disorder, Fourth Edition (DSM-IV) based on clinical assessment
A score of 20 or more on the Adult ADHD Investigator Symptom Report Scale (AISRS)
EFDs as established by at least 2 abnormal (>65) subscales of BRIEF-A

Exclusion Criteria

A history of non-response or intolerance to methylphenidate at adequate doses as determined by the clinician
A history of non-response or intolerance to memantine at adequate doses as determined by the clinician
Pregnant or nursing females
A history of clinically unstable or significant other psychiatric conditions including suicidality, homicidality, bipolar disorder, psychosis, or current tic disorder, as judged by the clinician
History of narrow angle glaucoma
Current (within 3 months) DSM-IV criteria for substance abuse or dependence
Medical condition or treatment that will either jeopardize subject safety or affect the scientific merit of the study, including cardiovascular disease, hypertension, history of renal or hepatic impairment, organic brain disorders, or history of seizure disorder.
Abnormal hematological or metabolic parameters
IQ < 80
Current use of any psychotropic medication
Lack of facility with the English language
Investigator and his/her immediate family; defined as the investigator's spouse, parent, child, grandparent, or grandchild

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	Subjects randomized to receive memantine-matched placebo in addition to open-label OROS-Methylphenidate
Placebo	OROS-Methylphenidate	Subjects randomized to receive memantine-matched placebo in addition to open-label OROS-Methylphenidate
Memantine	Memantine Hydrochloride	Subjects randomized to receive memantine in addition to open-label OROS-Methylphenidate
Memantine	OROS-Methylphenidate	Subjects randomized to receive memantine in addition to open-label OROS-Methylphenidate

Primary Outcome Measures

Name	Time	Method
Percent Change in Global Executive Composite T-Score on the Behavior Rating Inventory of Executive Function-Adult (BRIEF-A)	baseline, 12 weeks	This is a 75-item checklist with a large normative sample, internal consistency, test-retest reliability, inter-rater reliability, and external and concurrent validity, divided into nine empirically and theoretically derived and T-scored subscales: Inhibit, Shift, Emotional Control, Self-Monitor, Initiate, Working Memory, Plan/Organize, Task Monitor, and Organization of Materials. Example item: "I make careless errors when completing tasks." Items are rated 1 "Never," 2 "Sometimes," or 3 "Often." The Global Executive Composite (GEC) Score is calculated by totaling all items on the scale. GEC T-scores range from 34-108, with higher scores indicating more difficulties with executive function.

Secondary Outcome Measures