Conditions: Schizophrenia
Keywords: Negative symptoms NMDA Glutamate Glycine
Allocation: NON_RANDOMIZED | Intervention model: SINGLE_GROUP
Enrollment: 55
Healthy volunteers: no

Brief summary:
This study will determine whether increasing D-serine within the body will improve negative symptoms and cognitive impairments in people with schizophrenia.

Detailed description:
Schizophrenia is a life-long brain disorder affecting approximately 1 percent of Americans each year. Schizophrenia can be extremely disabling, causing people to hear voices, experience paranoia or hallucinations, believe that others are controlling their thoughts, and even fail at maintaining a job or caring for themselves. Current medications help to relieve most of these symptoms, but not all. Some people with schizophrenia still suffer from negative symptoms, such as difficulty with talking, expressing emotions, and motivation; they may also suffer from cognitive impairments, such as decreased concentration and memory loss. D-serine, an amino acid found within the body, activates brain cell receptors that appear to play a role in learning and memory. This study will determine whether adding a D-serine solution to a stable antipsychotic medication regimen will decrease negative symptoms in people with schizophrenia.

Participants in this open-label study will remain on their regular medication regimen for at least 2 weeks. During this time and before starting treatment, participants will be interviewed about their emotional problems, marital status, education, family background, employment history, and any drug or alcohol problems. Participants will also undergo a physical exam, an electrocardiogram (EKG), vital sign measurements, psychological tests, cognitive tasks, and an electroencephalogram (EEG). Participants will then begin 4 weeks of treatment with D-serine. In addition to participants' regular medication regimen, they will drink a D-serine powder mixed with water twice daily. Every 2 weeks, participants will undergo a physical exam and an interview about any changes in symptoms or emotional problems that they may be experiencing. Blood and urine samples will be taken throughout the study. After 4 weeks, participants will undergo an EKG, EEG, and the same psychological tests and cognitive tasks completed prior to treatment. A follow-up visit will occur 2 weeks post-treatment to monitor any changes in negative symptoms.

Arms:
arm 1: D-serine 30 mg/kg arm 2: D-serine 60 mg/kg arm 3: D-serine 120 mg/kg

Interventions: intervention 1: D-serine intervention 2: D-serine intervention 3: D-serine intervention 4: D-serine
Intervention descriptions: intervention 1: D-serine at following dose levels: 30 mg/kg, 60 mg/kg, and 120 mg/kg. PK/PD studies done at day 1. Medication will be administered as powder dissolved in liquid given in two divided doses daily for 4 weeks. intervention 2: None intervention 3: None intervention 4: None

Protocol document: