Memantine Treatment Study of Pathological Gambling

A Phase II Open-Label Multi-Center Trial of Memantine (Namenda(TM)) Treatment of Pathological Gambling

The goal of the proposed study is to evaluate the efficacy and safety of the drug memantine in individuals with pathological gambling (PG). Thirty subjects with DSM-IV PG will receive 10 weeks of open-label treatment with memantine. The hypothesis to be tested is that memantine will be effective and well tolerated in patients with PG. We hypothesize that memantine will reduce the severity of gambling symptoms and improve patients' overall functioning. This study will provide needed data on the treatment of a disabling disorder that currently lacks a clearly effective treatment.

Inclusion Criteria:

• Clinical diagnosis of Pathological Gambling using the clinician-administered Structured Clinical Interview for Pathological Gambling (SCI-PG) (Grant et al., 2004);
• Gambling behavior within 2 weeks prior to enrollment;
• For women, negative results on a urine pregnancy test and stable use of a medically accepted form of contraception.

Exclusion Criteria:

• Infrequent gambling (i.e. less than one time per week) that does not meet DSM-IV criteria for PG;
• Unstable medical illness or clinically significant abnormalities on laboratory tests, EKG, or physical examination at screen;
• History of seizures;
• Myocardial infarction within 6 months;
• Current pregnancy or lactation, or inadequate contraception in women of childbearing potential;
• A need for medication other than memantine with possible psychotropic effects or unfavorable interactions;
• Clinically significant suicidality;
• Current Axis I disorder determined by the SCID and SCID-compatible modules for impulse control disorders (Grant et al., 2005), except for nicotine dependence;
• Lifetime history of bipolar disorder type I or II, dementia, schizophrenia, or any psychotic disorder determined by SCID;
• Current or recent (past 3 months) DSM-IV substance abuse or dependence;
• Positive urine drug screen at screening;
• Initiation of psychotherapy or behavior therapy within 3 months prior to study baseline;
• Previous treatment with memantine;
• Treatment with investigational medication or depot neuroleptics within 3 months, with fluoxetine within 6 weeks, or with other psychotropics within 2 weeks prior to study baseline.