D-Serine Treatment For Tardive Dyskinesia

Study Overview
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Brief Summary
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Presently no generally effective treatments for tardive dyskinesia (TD) are available. D-serine is a naturally occurring amino acid that acts in-vivo as positive allosteric modulator at the glycine site associated with the glutamatergic NMDA receptor. Previous studies have suggested that D-serine may improve motor symptoms, including dyskinesias, which are caused by treatment with presently used antipsychotics drugs. The hypothesis under investigation in the present study is that D-serine adjuvant treatment may improve TD in schizophrenia patients diagnosed with this disorder.

Official Title
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D-SERINE TREATMENT FOR TARDIVE DYSKINESIA

Conditions
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Schizophrenia and Schizoaffective Disorder, Tardive Dyskinesia

Intervention / Treatment
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* Dietary Supplement: D-serine
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age 18-70; diagnosis of schizophrenia/schizoaffective disorder according to DSM-IV criteria; diagnosis will be made on the basis of SCID interview and information from medical records, previous treating psychiatrists, and family informants; history of ≥3 months antipsychotic drugs treatment and present stable dose antipsychotic treatment for at last 4 weeks; fulfillment of Schooler-Kane TD research criteria on a first evaluation performed 2-12 weeks prior to study entrance and on a subsequent evaluation performed prior to allocation to experimental treatment. Exclusion Criteria: meeting criteria for other DSM-IV Axis I diagnoses; presence of a neurological disorder or history of significant head injury; substance abuse or alcoholism during entire lifetime; are judged clinically to be at suicidal or homicidal risk; female patients who are pregnant or lactating; female patients who are not pregnant or lactating, if sexually active, must be using medically accepted means of contraception.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: D-serine adjuvant treatment<br>Random assignment, parallel group, double blind, placebo controlled 8 weeks trial. First arm: D-serine adjuvant treatment, up to 4 g/day Second arm: Placebo adjuvant treatment | Dietary Supplement: D-serine<br> <br> |
| Placebo Comparator: Placebo adjuvant treatment<br>Random assignment, parallel group, double blind, placebo controlled 8 weeks trial. First arm: D-serine adjuvant treatment, up to 4 g/day Second arm: Placebo adjuvant treatment | Dietary Supplement: Placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in AIMS total score |  | biweekly during a period of 8 weeks |