Depressive symptoms are associated with poor outcomes, increased risk of relapse and high suicide rates in patients with schizophrenia and schizoaffective disorder (1, 2).

Assess the efficacy of quetiapine XR (QTP-XR) versus risperidone on depressive symptoms in schizophrenia and schizoaffective disorder.

A randomised, open-label, parallel-group, flexible-dose study (NCT00640562).

LSM change from baseline to Week 12 in Calgary Depression Scale for Schizophrenia (CDSS) (3) score. Secondary endpoints: change in HAM-D and PANSS scores, and adverse events (AEs). No scorrection for multiplicity was done for the secondary endpoints.

216 patients received QTP-XR (n = 109; 400–800 mg/day) or risperidone (n = 107; 4–6 mg/day). From baseline, QTP-XR significantly reduced CDSS, HAM-D and PANSS negative total scores compared with risperidone (QTP-XR vs risperidone: -7.31 versus -5.53, p = 0.0107; -14.68 versus -11.53, p = 0.0005; -8.23 versus -5.45, p = 0.0008, respectively). No major differences in AEs were observed between QTP-XR and risperidone. Four serious AEs were experienced with QTP-XR and 5 with risperidone. Two patients receiving QTP-XR died (unrelated to study drug). Prolactin levels were significantly reduced from baseline with QTP-XR versus risperidone (-9.15 ng/mL and +22.18 ng/mL respectively; p < 0.0001). No important differences were seen in other laboratory parameters.

In this study, QTP-XR was superior to risperidone at reducing depressive symptoms in schizophrenia or schizoaffective disorder according to CDSS, HAM-D and PANSS negative scores.