A D1 Agonist For Working Memory

Overview

The purpose of the study is to examine the effects of the administration of a drug called DAR-0100A on attention and memory in persons with schizotypal personality disorder (SPD). DAR-0100A has not been FDA approved, however in recent studies has been used to treat cognitive deficits, meaning problems in the way you organize your thinking, in people diagnosed with schizophrenia. Many people who carry a diagnosis of schizotypal personality disorder have trouble with attention and memory. Increasing the presence of a brain chemical called dopamine has been found to help people with schizophrenia with their attention and memory problems. This study will investigate whether the same is true for people with schizotypal personality disorder by using DAR-0100A, a drug that has been shown to help with the cognitive deficits of people with Parkinson's disease by increasing dopamine effects. Information collected in this experiment may lead to a better understanding of the brain mechanisms involved in schizotypal personality disorder and improve treatments for the psychological problems associated with this condition.

Primary Aims: 1. To perform a 5-year study in which three consecutive days of DAR-0100A at a dose of 15 mg or placebo are administered intravenously over 30 minutes to 60 patients with SPD (12/yr) in a between-groups, randomized, double-blind design. Cognitive testing will be performed at baseline (Visit 1) and on the third day of drug/placebo administration (Visit 4). Subjects will return a minimum of two weeks later for Visit 5 to receive drug (if randomized initially to placebo) or placebo (if randomized to drug) in a double blind fashion in an identical protocol. This allows all patients to receive drug for Secondary Aim 1 while maintaining the blind. Baseline (Visit 1) and repeat cognitive testing (Visit 4) is also administered to 60 healthy controls per year (12/yr). The cognitive tests of working memory serving as primary outcome measures will include the modified AX-CPT (accuracy scores for AX, AY and BX and ANOVA), the N-back (delta difference 0-back-2-back), and the Paced Auditory Serial Addition Task (PASAT) (% correct and ANOVA). Other tests included are tests of working and verbal memory, executive function, and verbal learning for secondary outcome measures as well as comparison tests not hypothesized to change with drug. 2. To compare changes on the primary outcome measures from baseline to Visit 4 testing between drug and placebo administration in SPD subjects. 3. To compare primary outcome variables from baseline to Visit 4 between patients groups and healthy controls. 4. To obtain plasma DAR-0100A concentrations on Visit 4 to evaluate plasma concentrations in relation to cognitive changes as a potential covariate. Secondary Aims: 1. To evaluate the change between baseline and Visit 4 cognitive testing in all SPD patients receiving drug in the first or second phase. 2. To evaluate secondary outcome and comparison variables between SPD patients on placebo and drug. Primary Hypotheses: 1\. Baseline primary outcome measures will be impaired in SPD subjects compared to controls. 2. SPD subjects on DAR-0100A will show improvement on primary measures greater than healthy controls and SPD patients randomized to placebo between baseline and Visit 4. 3\. SPD patients will show significant improvements on primary outcome variables on drug compared to placebo but not on comparis-on perceptual (JLOT) and processing speed/attentional tasks (Trails A).