The efficacy of quetiapine XR was investigated in patients with major depressive disorder and differing levels of baseline severity. Pooled data from four placebo-controlled monotherapy studies of quetiapine XR (50–300 mg/day) were analyzed. Post-hoc analyses were carried out to assess change from baseline in the Montgomery Åsberg Depression Rating Scale (MADRS) total score at endpoint (week 6 or 8) to week 1, and response (≥50% reduction in MADRS total score) and remission (MADRS total score≤10) rates at endpoint for all patients and six baseline severity cohorts (MADRS total score ≥24, ≥26, ≥28, ≥30, ≥32, and ≥34). In total, 1752 patients (all patients) were evaluated (MADRS score at baseline: ≥24, n=1601; ≥26, n=1467; ≥28, n=1269; ≥30, n=1038; ≥32, n=745; and ≥34, n=500). At endpoint, quetiapine XR reduced MADRS total score in all patients (P<0.001) and each severity cohort (≥24, ≥26, ≥28, ≥30, and ≥32, P<0.001; ≥34, P<0.01) versus placebo. Quetiapine XR also improved MADRS total score at week 1, response rates for each severity cohort, and remission rates in five out of six severity cohorts, versus placebo. Quetiapine XR monotherapy showed antidepressant effects in patients with major depressive disorder across different levels of baseline severity.
aDepartment of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
bDepartment of Psychiatry, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts
cDepartment of Psychiatry, UT Southwestern Medical Center-Dallas, Dallas, Texas
eAstraZeneca Pharmaceuticals, Wilmington, Delaware, USA
fImperial College, University of London, London, UK
gDepartment of Psychiatry and Psychotherapy, University Hospital Carl Gustav Carus, Dresden, Germany
Previously poster presented at the 18th European Congress of Psychiatry, Munich, Germany, 27 February 2010–2 March 2010.
Previously poster presented at the 163rd Annual Meeting of the American Psychiatric Association, New Orleans, Los Angeles, USA, 22–26 May 2010.
Previously poster presented at the 50th Annual Meeting of the New Clinical Drug Evaluation Unit, Boca Raton, Florida, USA, 14–17 June 2010.
Correspondence to Michael E. Thase, MD, Department of Psychiatry, School of Medicine, University of Pennsylvania, 3535 Market Street, Philadelphia, Pennsylvania 19104, USA Tel: +1 215 746 6675; fax: +1 215 573 0759; e-mail: firstname.lastname@example.org
Received October 1, 2012
Accepted February 1, 2013