title: Clozapine alone versus clozapine and risperidone with refractory schizophrenia.
abstract: BACKGROUND
  The treatment of schizophrenia with multiple antipsychotic drugs is common, but the benefits and risks are not known.
  
  
  METHODS
  In a randomized, double-blind study, we evaluated patients with schizophrenia and a poor response to treatment with clozapine. The patients continued to take clozapine and were randomly assigned to receive eight weeks of daily augmentation with 3 mg of risperidone or with placebo. This course of treatment was followed by an optional 18 weeks of augmentation with risperidone. The primary outcome was reduction in the total score for severity of symptoms on the Positive and Negative Syndrome Scale (PANSS). The secondary outcomes included cognitive functioning.
  
  
  RESULTS
  A total of 68 patients were randomly assigned to treatment. In the double-blind phase, the mean total score for the severity of symptoms decreased from baseline to eight weeks in both the risperidone and the placebo groups. There was no statistically significant difference in symptomatic benefit between augmentation with risperidone and placebo: 9 of 34 patients receiving placebo and 6 of 34 receiving risperidone responded to treatment (P=0.38). The mean difference in the change in PANSS scores from baseline to eight weeks between those receiving risperidone and those receiving placebo was 0.1 (95 percent confidence interval, -7.3 to 7.0). The verbal working-memory index showed a small decline in the risperidone group and a small improvement in the placebo group (P=0.02 for the comparison between the two groups in the change from baseline). The increase in fasting blood glucose levels was mildly greater in the risperidone group than in the placebo group (16.2 vs. 1.8 mg per deciliter [0.90 vs. 0.10 mmol per liter], P=0.04). The incidence and severity of other side effects did not differ between the two groups.
  
  
  CONCLUSIONS
  In this short-term study, the addition of risperidone to clozapine did not improve symptoms in patients with severe schizophrenia. (ClinicalTrials.gov number, NCT00272584).
authors.affiliation: Centre for Complex Disorders and the Department of Psychiatry, University of British Columbia, Vancouver General Hospital Research Pavilion, Vancouver, Canada. honer@interchange.ubc.ca
authors.forename: William G
authors.initials: WG
authors.lastname: Honer
authors.forename: Allen E
authors.initials: AE
authors.lastname: Thornton
authors.forename: Eric Y H
authors.initials: EY
authors.lastname: Chen
authors.forename: Raymond C K
authors.initials: RC
authors.lastname: Chan
authors.forename: Jessica O Y
authors.initials: JO
authors.lastname: Wong
authors.forename: Andrea
authors.initials: A
authors.lastname: Bergmann
authors.forename: Peter
authors.initials: P
authors.lastname: Falkai
authors.forename: Edith
authors.initials: E
authors.lastname: Pomarol-Clotet
authors.forename: Peter J
authors.initials: PJ
authors.lastname: McKenna
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Stip
authors.forename: Richard
authors.initials: R
authors.lastname: Williams
authors.forename: G William
authors.initials: GW
authors.lastname: MacEwan
authors.forename: Kishor
authors.initials: K
authors.lastname: Wasan
authors.forename: Ric
authors.initials: R
authors.lastname: Procyshyn
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D003024:Clozapine / Q000009:adverse effects / Q000627:therapeutic use*; D003071:Cognition / Q000187:drug effects; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D018967:Risperidone / Q000009:adverse effects / Q000627:therapeutic use*; D012559:Schizophrenia / Q000188:drug therapy*; D012565:Schizophrenic Psychology; D017211:Treatment Failure
chemical_list: D014150:Antipsychotic Agents; D003024:Clozapine; D018967:Risperidone