news
PSTT Vol. 3, No. 11 November 2000
update
Seroquel offers hope for bipolar patients David Bradley, tel/fax: 144 1954 202218, Web: http://www.sciencebase.com
Phase III clinical trials of AstraZeneca’s (Macclesfield, UK) Seroquel (quetiapine fumarate) tablets will provide efficacy information for the drug in treating bipolar disorder for patients experiencing acute mania. Bipolar disorder, previously known as manic depression, is a serious mental illness affecting 1–3% of the population. The National Institute of Mental Health (Bethesda, MD, USA) estimates that there are more than two million people in the USA who have been diagnosed with this disorder. Symptoms are variable but tend to involve mania, impaired judgement, hallucinations and mood swings. The disorder is generally described as being of a cyclical nature with patients fluctuating between emotional states described as painful elation to absolute despair. It is the double-edged nature of the symptoms that gives rise to its more politically correct name. The impact on the bipolar patient, and their family and friends, of failing to effectively treat the disorder can be serious. The manic state is often associated with severe irritability, impatience, impulsiveness and other severe emotions. Bipolar disorder changes lives, seriously affects relationships and can, in the extreme, lead to suicide or homicide. Atypical treatment AstraZeneca’s drug Seroquel has previously been seen purely as an atypical antipsychotic for treating schizophrenia and depressive symptoms in patients with psychotic disorders1. As such, it has been available in the USA on prescription for treating the disorder for more than 600,000 patients since its approval in September 1997. A Phase III trial instigated in August this year now seeks to demonstrate its efficacy on sufferers of bipolar disorder. Seroquel, like the related atypical antipsychotic clozapine, is a low potency D-2 dopamine (DA) receptor antagonist and a 5-HT2-receptor antagonist, which is more potent than the ‘typical’ antipsychotics developed in the 1950s and 1960s to augment or replace ‘lithium’ therapy for mental disorders.
The first element of the AstraZeneca program will be a standard double-blind, randomized, placebo-controlled trial of Seroquel used in conjunction with a mood-stabilizing agent. Mood stabilizers are commonly used in conjunction with a second drug for treating and/or controlling mental disorders. A total of 178 bipolar patients suffering episodes of acute mania will take part in the trial across more than 40 medical centres in the USA. The study will last three weeks and patients will be assessed using the Young-Mania Rating Scale (YMRS), a global rating of the severity of mania in bipolar disorder, and other clinical assessment tools.
been supported by several placebo- and comparator-controlled Phase II and III clinical trials of more than 4000 male and female hospitalized patients with acute exacerbation of chronic or subchronic schizophrenia. However, as with other antipsychotics, caution is recommended for use in patients with a history of seizures or with conditions that can potentially lower the seizure threshold. Common adverse reactions seen in trials are headache (19%), somnolence (18%) and dizziness (10%), although these were classed as mild to moderate. References 1 Saller, C.F. and Salama, A.I. (1993) Seroquel: biochemical profile of a potential atypical
Stabilizing mood The treatment of bipolar patients usually involves the use of a mood stabilizer and an antipsychotic, both of which can have severe side effects, such as weight gain, sexual dysfunction, raised plasma prolactin levels, dry mouth, constipation and so-called extrapyramidal symptoms. These side effects are among the common reasons why patients stop taking their medication and undergo a relapse. AstraZeneca hope that the use of Seroquel with a mood stabilizer will produce fewer side effects than conventional therapies. Indeed, research has shown that patients taking Seroquel gained less than 2.5 kg on average over a ten-week period and an average of just under 2.75 kg in total after 12 months2. Other antipsychotics, although not all, are associated with weight gain of more than 4 kg. As with other antipsychotics, AstraZeneca points out that Seroquel can, in rare instances, lead to tardive dyskinesia (which is often associated with long-term use of antipsychotic agents) and neuroleptic malignant syndrome (neuromuscular symptoms include muscle rigidity, fever and an irregular pulse). These conditions are among the known extrapyramidal symptoms, which also include akinesia (slowed movement) and akathisia (restless limbs). According to AstraZeneca, the efficacy of Seroquel used as an atypical antipsychotic has
antipsychotic. Psychopharmacology (Berl.) 112, 285–292 2 Jones, A.M. et al. (2000) Weight changes in
1461-5347/00/$ – see front matter ©2000 Elsevier Science Ltd. All rights reserved. PII: S1461-5347(00)00308-4
patients treated with quetiapine. American Psychiatric Association Annual Meeting, 13–18 May, Chicago, USA
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