Quetiapine augmentation in depressed patients with partial response to antidepressants

Clinical trials suggest between 30-50% of depressed patients have an inadequate outcome to antidepressant pharmacotherapy. Among the approaches to improve outcome has been augmentation with antipsychotic medications. We aim to investigate the efficacy and tolerability of augmentation with quetiapine in depressed patients with a partial response to antidepressants.

Patients with a Major Depressive Disorder (DSMIV) who had partial/no response to a stable dose of an Selective Serotonin Reuptake Inhibitors (SSRI)/SNRI were recruited. All patients received add-on quetiapine (200-600 mg nocte) in a 6-week trial. Outcome measures (HAMD, MADRS) were assessed at screening, baseline, weeks 1, 2, 4 and 6. Extrapyramidal symptoms (EPSEs) were assessed at baseline, weeks 2, 4 and 6. A neuropsychological battery of tests was administered at baseline, weeks 3 and 6.

Nineteen patients entered the trial and 18 completed the trial per protocol. We report a rapid improvement in depression ratings over 6 weeks (p < 0.0005) and remission rates of 67% at week 1 and 94% at week 6. There was no evidence of EPSE and no worsening (and some improvement) of cognition.

This suggests clinical benefits of quetiapine augmentation of SSRI/SNRI antidepressants with no worsening, and possible improvements in cognition.