Effect of therapy with atypical antipsychotic drugs on prolactin concentration in patients with schizophrenia and schizoaffective disorders

Multi-center, randomized, double-blind, placebo-controlled study of quetiapine extended-release formulation in Japanese patients with bipolar depression

RATIONALE

Quetiapine fumarate is an atypical antipsychotic indicated for various mental disorders, but it has not been studied in Japanese patients with bipolar depression.

OBJECTIVES

To evaluate the efficacy and safety of quetiapine XR (extended release) in Japanese patients with bipolar depression.

METHODS

In this multi-center, randomized, double-blind, placebo-controlled, fixed-dose study of 431 Japanese adults with bipolar I or II disorder, efficacy was determined by analyzing the mean change from baseline in Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Secondary end points included MADRS response and remission rates, Hamilton Depression Scale 17-Item (HAM-D₁₇), and Clinical Global Impressions-Bipolar (CGI-BP) scale scores. Safety was determined by monitoring adverse events and clinical assessments.

RESULTS

This study revealed a statistically significantly greater decrease in MADRS total score after 8 weeks of quetiapine XR 300 mg/day monotherapy compared with placebo (- 12.6 vs. - 10.1; p = 0.034). There were also improvements in MADRS response (44.1 vs. 35.6%) and remission (38.0 vs. 26.6%) rates as well as in HAM-D₁₇ and CGI-BP scale scores compared with placebo. In the subgroup analysis of patients with bipolar I or II disorder, the adjusted mean changes in MADRS total score compared to placebo were - 2.3 and - 2.1, respectively. Adverse events occurred in 149 patients (83.2%) receiving quetiapine XR 300 mg/day and in 81 patients (45.8%) receiving placebo. The most common adverse events were somnolence and thirst, which is consistent with the previously reported safety profile.

CONCLUSIONS

Once-daily monotherapy with quetiapine XR is an effective and well-tolerated treatment for bipolar depression in Japanese patients.

Pituitary volume and early treatment response in drug-naïve first-episode psychosis patients

BACKGROUND

An early response to antipsychotic treatment in patients with psychosis has been associated with a better course and outcome. However, factors that predict treatment response are not well understood. The onset of schizophrenia and related disorders has been associated with increased levels of stress and hyper-activation of the hypothalamic-pituitary-adrenal (HPA) axis. This study examined whether pituitary volume at the onset of psychosis may be a potential predictor of early treatment response in first-episode psychosis (FEP) patients.

METHODS

We investigated the relationship between baseline pituitary volume and symptomatic treatment response over 12 weeks using mixed model analysis in a sample of 42 drug-naïve or early treated FEP patients who participated in a controlled dose-finding study of quetiapine fumarate. Logistic regression was used to examine predictors of treatment response. Pituitary volume was measured from magnetic resonance imaging scans that were obtained upon entry into the trial.

RESULTS

Larger pituitary volume was associated with less improvement in overall psychotic symptoms (Brief Psychiatric Rating Scale (BPRS) P=0.031) and positive symptoms (BPRS positive symptom subscale P=0.010). Regardless of gender, patients with a pituitary volume at the 25th percentile (413 mm(3)) were approximately three times more likely to respond to treatment by week 12 than those at the 75th percentile (635 mm(3)) (odds ratio=3.07, CI: 0.90-10.48).

CONCLUSION

The association of baseline pituitary volumes with early treatment response highlights the importance of the HPA axis in emerging psychosis. Potential implications for treatment strategies in early psychosis are discussed.