Tetrabenazine for Partial Responders

• Status: Completed
• Trial end date: 2006-01-01
• Target enrollment: 0
• Participant gender: All

Summary

Purpose of Study:

A) To improve outcome in large population of antipsychotic patients with schizophrenia or schizoaffective who are only partial responders B) To increase understanding of pharmacology and mechanisms of action underlying antipsychotic effect

Hypothesis/Objectives of the Study:

Tetrabenazine, through its pre-synaptic action, should augment the post-synaptic effects of an antipsychotic.

Background and Rationale for the study:

Preliminary evidence that other amine-depleting agents e.g., reserpine, can induce such an effect

• Phase: N/A
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Centre for Addiction and Mental Health
• Collaborator: Stanley Medical Research Institute
• Treatments: Antipsychotic Agents; Tetrabenazine

Criteria

Inclusion Criteria:

• has been on an antipsychotic medication for at least 3 months and achieved the maximum dose vis à vis tolerability/side effects.

• Partial response to antipsychotic medication (CGI > 4; BPRS [Anchored, 18-item] total > 30; single item score > 4 on 2 positive symptom items)

• has been on at least 2 previous antipsychotic trials of 4-6 weeks in duration at a dose reaching 400-600 mg chlorpromazine (or equivalent) with no clinical improvement

Exclusion Criteria:

• age < 18 or > 65

• previous documentation of hypersensitivity to tetrabenazine

• SCID criteria for a current depressive episode

• MAOI administration within 2 weeks of tetrabenazine treatment

• concomitant desipramine use

• diagnosis of idiopathic Parkinson's disease and/or levodopa treatment

• current unstable medical illness and current substance abuse