BOLDER II STUDY CONFIRMS THERAPEUTIC POTENTIAL OF SEROQUEL IN BIPOLAR DEPRESSION

Newly released top-line results from the BOLDER II (BipOLar DEpRession) study have underlined the potential for SEROQUEL (quetiapine fumarate) in the treatment of patients with major depressive episodes associated with bipolar disorder. Based on prior discussions with the US Food and Drug Administration (FDA) and the results of BOLDER II, AstraZeneca plans to file for a US licence extension for SEROQUEL in the treatment of depressive episodes associated with bipolar disorder around the end of this year (2005).

BOLDER II - an eight week, multi-centre, placebo-controlled study - found that SEROQUEL 300mg and 600mg doses achieved a statistically significant reduction in levels of bipolar depression compared with placebo (p-value less than or equal to 0.001), as measured by the change from baseline in Montgomery-Åsberg Depression Rating Scale (MADRS) total score.

The significant reduction in MADRS total score was seen both in patients with bipolar I and bipolar II disorder, in patients with or without a rapid cycling course of illness, and as early as week one after randomisation. Significant improvements were also seen compared with placebo in the various secondary study endpoints among SEROQUEL-treated patients, including reduction of anxiety symptoms. In addition, more than half (53 per cent) of patients receiving SEROQUEL achieved remission from their bipolar depression symptoms.

BOLDER II reinforces the findings of the landmark BOLDER I study published in American Journal of Psychiatry in July 2005, which first indicated a significant effect for SEROQUEL in treating major depressive episodes associated with bipolar disorder. Importantly, SEROQUEL was shown to be well tolerated in BOLDER II with a similar safety profile seen to that in BOLDER I. The rate of serious adverse events was low, and comparable in all treated groups. The most common adverse events reported in the trial were dry mouth, sedation, somnolence, dizziness and constipation. There was a low incidence of treatment-emergent mania in the SEROQUEL-treated groups. As in BOLDER I, there was a low incidence of EPS (extrapyramidal symptoms) and minimal weight change reported in the study.

Patients with bipolar depression are underserved and understudied. The findings from the BOLDER II study are very encouraging and support the findings of BOLDER I, in showing the potential of SEROQUEL, as monotherapy, for the acute treatment of bipolar depression. Each of these two studies represent the largest placebo-controlled short-term studies ever conducted in bipolar depression. The beneficial risk:benefit profile of SEROQUEL seen in both studies could offer an important therapeutic value for both patients and physicians as there is currently only one FDA approved therapy to treat depressive episodes associated with bipolar disorder.

Bipolar disorder is a serious mental illness that affects approximately 3-4 per cent of the adult population and is the sixth leading cause of disability in the world. Patients with bipolar disorder are symptomatic almost half of their lives, and approximately two-thirds of that time is spent in the depressed phase of the illness.

SEROQUEL has been licensed for the treatment of schizophrenia since 1997 and is available in 85 countries for the treatment of this condition. It is currently licensed for the treatment of mania associated with bipolar disorder in 73 countries. In the first half of 2005, SEROQUEL sales reached $1,300 million.

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21st October 2005

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