The study was stopped after 4 years of recruitment difficulties.

The purpose of this study is to determine the tolerability of the medication cysteamine bitartrate on schizophrenia patients and to evaluate the effect of the medication on the symptoms of schizophrenia.

Despite the availability of numerous antipsychotics, the treatment of schizophrenia is very unsatisfactory. Many patients have persistent positive psychotic symptoms or negative symptoms despite treatment, and any improvement in cognitive function is small. New approaches to the pharmacotherapy of schizophrenia that are not based primarily on dopaminergic blockade are needed.

The rationale for a trial of cysteamine comes from the evidence that cysteamine increases brain concentrations of brain-derived neurotrophic factor.

We will conduct an open-label study of tolerability and efficacy of cysteamine as an adjunct to second-generation antipsychotics in schizophrenia and schizoaffective subjects with partially responsive symptoms.

Our objectives are to determine the safety and tolerability of cysteamine administered as an adjunct to second-generation antipsychotic drugs in adult outpatients with partially-responsive schizophrenia. Additionally, we are evaluating the effect of cysteamine on the positive and negative symptoms of schizophrenia as measured by changes in the Positive and Negative Symptom Scale (PANSS), and on cognitive impairment as measured by the Brief Assessment of Cognition in Schizophrenia (BACS).

Inclusion Criteria:

• Diagnosis of schizophrenia or schizoaffective disorder

• 18-60 years of age

• Residual symptoms, as defined by both 1 & 2:

  1. At least one PANSS positive symptom item score > 4, or at least two items with a score > 3
  2. At least one PANSS negative symptom item score > 4, or at two items with a score > 3

• No clinically significant change in symptoms for at least one month

• On the same psychotropic medication(s) > 2 weeks

• Taking a second-generation antipsychotic (olanzapine, risperidone, quetiapine, ziprasidone, aripiprazole, or clozapine)

• Provision of written informed consent

Exclusion Criteria:

• Meets criteria for current major depressive disorder
• Abnormal hepatic function (AST or ALT > 2.5 X the upper limit of normal, or bilirubin > 1.5 X the upper limit of normal)
• Abnormal renal function (BUN or creatinine > 1.5 X the upper limit of normal)
• Presence of any unstable or untreated medical disorder
• Any history of seizure disorder, HIV, or diagnosis of AIDS
• Any abnormal lab test result that is judged to be clinically significant by the investigators
• Pregnancy, breast feeding, or female and of child-bearing potential who is not using any contraceptive method
• Present danger to self or others

Recruitment challenges for this study are the number of pills that the subjects are required to take during treatment and the reported foul body odor that the subjects complianed of and was also noted by the Investigator and research staff.