Efficacy and tolerability of quetiapine in patients with schizophrenia who switched from haloperidol, olanzapine or risperidone

Abstract

A post hoc analysis of the SPECTRUM trial was carried out to evaluate whether the improvements in efficacy and tolerability gained on switching to quetiapine occurred consistently for patients previously treated with either: haloperidol (n = 43); olanzapine (n = 66); or risperidone (n = 55) monotherapy. Patients were initiated with quetiapine to 400 mg/day over 7 days, and then flexibly dosed (300-750 mg/day) for 11 weeks. The mean (SD) modal dose of quetiapine was 501 (138) mg/day in the haloperidol subgroup, 472 (147) mg/day in the olanzapine subgroup and 485 (141) mg/day in the risperidone subgroup at the study endpoint. Switching to quetiapine induced significant improvements from baseline in PANSS scores, with least square mean changes in total scores of -32.5, -15.4, and -18.5 for patients previously treated with haloperidol, olanzapine and risperidone, respectively, (all p < 0.001 vs baseline). Significant improvements were also noted in CDSS scores, particularly for patients clinically depressed at baseline (all p < 0.001 vs baseline). There were significant reductions in EPS on the SAS and BAS for all subgroups (all p < 0.001 vs baseline). Switching to quetiapine produced efficacy and tolerability benefits regardless of whether their previous antipsychotic was haloperidol, olanzapine or risperidone.

Quetiapine in the treatment of schizophrenia and related disorders

“…Quetiapine showed, in certain cases, marked amelioration of acute EPS induced by the previously administered medication. Furthermore these results could have been confirmed by a recently published post hoc analysis of the SPECTRUM trial which was carried out to evaluate whether the improvements in efficacy and tolerability gained on switching to quetiapine occurred consistently for patients previously treated with an antipsychotic monotherapy (Larmo et al 2005). Switching to quetiapine showed a significant improvement in terms of efficacy and tolerability regardless of whether their previous antipsychotic was haloperidol, olanzapine, or risperidone.…”

Long-term efficacy and tolerability of quetiapine in patients with schizophrenia who switched from other antipsychotics because of inadequate therapeutic response—a prospective open-label study

“…Although the difference in the modes of dosage should be noted (oral risperidone [ 10 , 11 ] and risperidone long-acting injection [ 12 , 13 ], oral quetiapine immediate [ 11 ] and extended release [ 9 , 12 ]), in general, quetiapine showed long-term effectiveness similar to [ 11 ] or less than risperidone [ 10 ], a positive relapse prevention effect better than placebo [ 9 ] and equal to risperidone [ 12 ] except for its ability to achieve remission, which was less than risperidone [ 12 , 13 ]. When focused on studies that switched over to quetiapine, Larmo and his colleagues (2005) showed significant improvement in the Positive and Negative Syndrome Scale (PANSS) positive, negative, and general psychopathology subscales after switching to quetiapine in patients who were previously treated with low-dose haloperidol, risperidone, or olanzapine [ 14 ]. Recently, Chue et al (2013) reported another open-label, prospective study to evaluate long-term clinical benefits of switching to quetiapine extended release from an oral antipsychotic in patients with schizophrenia.…”

A Double-Blind, Placebo-Controlled Pilot Trial of Quetiapine for the Treatment of Type A and Type B Alcoholism

“…24,25 Quetiapine has a good safety profile compared with conventional antipsychotics, as well as other atypicals. 26,27 Based on its activity at both dopaminergic and serotonergic receptors, and its excellent safety profile, quetiapine is a promising pharmacotherapy for treating alcoholics. It may be particularly well suited for treating the more severely addicted, comorbidly complicated, Type B alcoholics.…”