Aripiprazole vs Risperidone Head-to-Head Effectiveness in First-Episode Non-Affective-Psychosis: A 3-Month Randomized, Flexible-Dose, Open-Label Clinical Trial

Abstract

Background: Antipsychotic choice for the acute phase of a first episode of psychosis (FEP) is of the utmost importance since it may influence long-term outcome. However, head-to-head comparisons between second-generation antipsychotics remain scarce. The aim of this study was to compare the effectiveness in the short term of aripiprazole and risperidone after FEP outbreak. Methods: From February 2011 to October 2018, a prospective, randomized, open-label study was undertaken. Two hundred-sixty-six first-episode drug-naïve patients were randomly assigned to aripiprazole (n = 136) or risperidone (n = 130) and followed-up for 12 weeks. The primary effectiveness measure was all-cause treatment discontinuation. In addition, an analysis based on intention-to-treat principle was conducted to assess clinical efficacy. Results: The overall dropout rate at 12 weeks was small (6.39%). Effectiveness measures were similar between treatment arms as treatment discontinuation rates (χ2= 0,409; P= .522), and mean time to all-cause discontinuation (log rank χ2 = −1.009; P= .316) showed no statistically significant differences. Despite no statistically significant differences between groups regarding clinical efficacy, aripiprazole required higher chlorpromazine equivalent dosage (χ2=2.160; P=.032) and extended mean time (W=8183.5; P=.008) to reach clinical response. Sex-related adverse events and rigidity were more frequent in the risperidone group, whereas sialorrhea was on the aripiprazole group. Conclusions: No differences regarding effectiveness were found between aripiprazole and risperidone for the short-phase treatment of FEP. Despite the importance of efficacy during this phase, differences in side effect profiles and patient’s preferences are essential factors that may lead clinical decisions for these patients.