Psychoses, Psychotic Disorders, Schizophrenias, Schizophrenic Disorders
Conditions
Keywords
Schizophrenia, sarcosine, D-serine, NMDA
Brief summary
Both GlyT-1 inhibitors and NMDA-glycine site agonists have been demonstrated to be beneficial for chronic schizophrenia patients. The purpose of this study is to compare efficacy and safety of add-on treatment of sarcosine, a GlyT-1 inhibitor, and D-serine, an NMDA-glycine site agonist, in chronically stable schizophrenia patients who have been stabilized with antipsychotics.
Detailed description
The etiology of schizophrenia remains unclear. Schizophrenia patients reveal positive symptoms, negative symptoms, and cognitive impairments. In addition to dopamine system hyperactivity, hypofunction of N-methyl-D-aspartate (NMDA) receptor plays a role in the pathophysiology of schizophrenia. Consequently, enhancing NMDA receptor neurotransmission has been regarded as a novel treatment approach. To date, there have been several reported trials on NMDA enhancers. Both sarcosine (N-methylglycine, a glycine transporter I inhibitor) and D-serine (a potent NMDA-glycine site agonist) showed therapeutic effects in chronically stable patients. Interestingly, sarcosine appeared more efficacious than D-serine in acutely exacerbated ones when added-on to antipsychotics. Both sarcosine and D-serine yielded excellent safety profiles. It remains unclear whether sarcosine can be also more efficacious than D-serine in the treatment for chronically stable schizophrenia. The aim of this project is to examine the efficacy and safety of add-on treatment of sarcosine vs. D-serine in chronically stable schizophrenia patients who have been stabilized with antipsychotics. In the study, 60-75 schizophrenic patients are recruited into the 6-week trial and randomly assigned into the three groups (2 gm/d sarcosine, 2 gm/d D-serine, or placebo) with a double-blind manner. Clinical manifestation (Positive and Negative Syndrome Scale \[PANSS\], side effects and quality of life (QOL) are evaluated every two weeks during the trial.. The efficacies of three groups are compared.
Interventions
DRUGSarcosine and D-serine
Sponsors
National Science and Technology Council, Taiwan
National Health Research Institutes, Taiwan
China Medical University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Fulfill the criteria of schizophrenia according to the Diagnostic and Statistic Manual, fourth edition (DSM-IV). * Agree to participate in the study and provide informed consent.
Exclusion criteria
* Meet DSM-IV criteria of major mood disorder, current substance dependence or mental retardation * History of epilepsy, head trauma or CNS diseases * Major, untreated medical diseases * Pregnancy or lactation
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Total scores of Positive and Negative Syndrome Scale (PANSS) and Quality of Life (QOL) | 6 weeks |
Secondary
| Measure | Time frame |
|---|---|
| Subscales of PANSS | 6 weeks |
Countries
Taiwan
Outcome results
None listed