This pilot study is an eight-week, randomized, double-blind, placebo-controlled, escalating dose trial of the novel vigilance-promoting drug, modafinil, added to a stable dose of clozapine in 40 patients with schizophrenia or schizoaffective disorder. Modafinil will be initiated at 100 mg/d. After 2 weeks, the study drug may be increased to 200 mg/d and after 4 weeks, study drug may be increased to a maximum of 300 mg/d. Dose escalation will be based upon persistence of sedation versus emergence of side effects.

This pilot study is an eight-week, randomized, double-blind, placebo-controlled, escalating dose trial of the novel vigilance-promoting drug, modafinil, added to a stable dose of clozapine in 40 patients with schizophrenia or schizoaffective disorder. Modafinil will be initiated at 100 mg/d. After 2 weeks, the study drug may be increased to 200 mg/d and after 4 weeks, study drug may be increased to a maximum of 300 mg/d. Dose escalation will be based upon persistence of sedation versus emergence of side effects.

1. Evaluate tolerability and safety of modafinil compared to placebo using the SAFTEE and vital signs.
2. Evaluate the effect size of modafinil compared to placebo upon wakefulness and fatigue using the Epworth Sleepiness Scale (ESS) and the Fatigue Severity Scale (FSS).
3. Evaluate the effect size of modafinil compared to placebo upon negative symptoms using the SANS total score.
4. Evaluate the effect size of modafinil compared to placebo upon cognitive functioning using a standard battery of cognitive tests.
5. Evaluate the effect size of modafinil compared to placebo upon weight, BMI, waist/hip circumference and fasting glucose and lipids.
6. Effect the variability of response in placebo and modafinil groups for each of the outcome measures.

Inclusion Criteria:

• Diagnosis of Schizophrenia, any subtype or schizoaffective disorder
• Ages 18-65 years
• Capable of providing informed consent, or capable of providing assent with a guardian who provides informed consent
• Stable dose of clozapine for at least 1 month
• Three months of stable psychotic symptoms

Exclusion Criteria:

• Serious medical or neurological illness (unstable cardiac disease, seizure disorder, malignancy, liver or renal impairment, etc.)
• Current substance abuse
• Pregnancy, nursing, or unwilling to use appropriate birth control measures during participation if female and fertile.
• Unable to complete neuropsychological tests
• History of serious blood dyscrasia requiring discontinuation of clozapine
• Serious suicidal or homicidal risk within the past six months
• Current treatment with a psychostimulant