title: Aripiprazole, an antipsychotic with a novel mechanism of action, and risperidone vs placebo in patients with schizophrenia and schizoaffective disorder.
abstract: BACKGROUND
  Aripiprazole is a dopamine D2 receptor partial agonist with partial agonist activity at serotonin 5HT1A receptors and antagonist activity at 5HT2A receptors. This multicenter trial examined the efficacy, safety, and tolerability of aripiprazole in patients with acute exacerbation of schizophrenia or schizoaffective disorder.
  
  
  METHODS
  In this 4-week double-blind study, 404 patients were randomized to 20 mg/d (n = 101) or 30 mg/d (n = 101) of aripiprazole, placebo (n = 103), or 6 mg/d of risperidone (n = 99). Efficacy assessments included Positive and Negative Syndrome Scale (PANSS) scores and Clinical Global Impression scores. Safety and tolerability evaluations included extrapyramidal symptoms and effects on weight, prolactin, and corrected QT (QTc) interval.
  
  
  RESULTS
  Aripiprazole (20 and 30 mg/d) and risperidone (6 mg/d) were significantly better than placebo on all efficacy measures. Separation from placebo occurred at week 1 for PANSS total and positive scores with aripiprazole and risperidone and for PANSS negative scores with aripiprazole. There were no significant differences between aripiprazole and placebo in mean change from baseline in the extrapyramidal symptom rating scales. Mean prolactin levels decreased with aripiprazole but significantly increased 5-fold with risperidone. Mean change in QTc interval did not differ significantly from placebo with any active treatment group. Aripiprazole and risperidone groups showed a similar low incidence of clinically significant weight gain.
  
  
  CONCLUSIONS
  Aripiprazole is effective, safe, and well tolerated for the positive and negative symptoms in schizophrenia and schizoaffective disorder. It is the first non-D2 receptor antagonist with clear antipsychotic effects and represents a novel treatment development for psychotic disorders.
authors.affiliation: Brain Imaging Center, University of California, Irvine, 92697, USA. sgpotkin@uci.edu
authors.forename: Steven G
authors.initials: SG
authors.lastname: Potkin
authors.forename: Anutosh R
authors.initials: AR
authors.lastname: Saha
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Kujawa
authors.forename: William H
authors.initials: WH
authors.lastname: Carson
authors.forename: Mirza
authors.initials: M
authors.lastname: Ali
authors.forename: Elyse
authors.initials: E
authors.lastname: Stock
authors.forename: Joseph
authors.initials: J
authors.lastname: Stringfellow
authors.forename: Gary
authors.initials: G
authors.lastname: Ingenito
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Marder
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000068180:Aripiprazole; D001480:Basal Ganglia Diseases / Q000139:chemically induced; D004311:Double-Blind Method; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D010879:Piperazines / Q000009:adverse effects / Q000627:therapeutic use*; D010919:Placebos; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D015363:Quinolones / Q000009:adverse effects / Q000627:therapeutic use*; D018967:Risperidone / Q000009:adverse effects / Q000627:therapeutic use*; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy*; D012565:Schizophrenic Psychology; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents; D010879:Piperazines; D010919:Placebos; D015363:Quinolones; D000068180:Aripiprazole; D018967:Risperidone