Pharmacoeconomics of quetiapine for the management of acute mania in bipolar I disorder

Abstract

Bipolar disorder (or manic depression) is a lifelong, severe and complex psychiatric illness characterized by recurrent episodes of depression and mania. The aim of this study is to explore the cost-effectiveness of quetiapine compared with other alternatives for the treatment of acute manic episodes in bipolar I disorder, with a specific focus on serious side effects. Four trials investigating quetiapine monotherapy and adjunctive therapy were performed to investigate the efficacy of quetiapine in patients with bipolar I disorder. Data were derived from The Netherlands Mental Health Survey and Incidence Study and used to construct a study population for the model. To assess the cost-effectiveness of quetiapine in the management of acute mania in bipolar I disorders, a discrete event simulation model of seven monotherapy and combination treatment options was developed. A comparison of the total costs demonstrates that all of the monotherapy options and placebo are more costly than the combination therapy options. The combinations of lithium with risperidone (euro2365) and with olanzapine (euro2429) are estimated to be less costly per patient than the combination of lithium with quetiapine (euro2555). A group of 10,000 patients switching from olanzepine/lithium to quetiapine/lithium would involve extra costs of euro1,260,000, but would prevent an estimated number of 362 serious side effects. Switching from risperidone/lithium to quetiapine/lithium would cost an additional euro1,900,000 and would prevent 1580 serious side effects. In terms of serious side effects, the combination of lithium/quetiapine was superior to the combination of lithium with olanzapine or risperidone. It must be considered whether the decreased likelihood of developing a severe side effect is worth the extra costs incurred with the combination of quetiapine/lithium.

Economic evaluations in bipolar disorder: a systematic review and critical appraisal

“…While the DES model built by Klok et al. satisfied the lowest number of quality criteria (49%), the DES model developed by Ekman et al. fulfilled the highest proportion (94%).…”

“…All of the modeling studies in our review had a clear definition of the decision problem, model objectives, and scope. Different modeling approaches were used to address the study question, including one decision tree model , eight cohort‐based Markov models , two DES studies , two publications using the same mathematical model , and two studies that failed to explicitly state their approach or structure . All studies except Klok et al.…”

“…All studies except Klok et al. specified the primary decision maker and perspective of the study. Nine studies adopted a health care provider perspective , three studies utilized a third‐party payer perspective , one study adopted a societal perspective , and two studies reported results using both third‐party payer and societal perspectives .…”

“…The DES model adopted by Klok et al. simulated a large number of individuals with BD‐I, where individual health state rewards were determined by patients' attributes such as age, gender, number of previous episodes, and co‐existing morbidity. However, structural assumptions behind the modeling process lacked transparency and it was not clear how they calculated and incorporated ‘time‐to‐event’ probabilities.…”

“…The majority of the studies used either meta‐analysis or individual RCTs to identify relative treatment effect sizes. Although individual effect sizes from RCTs may not be generalizable to other populations or settings, given the resource restraints, individual effect sizes from RCTs is still considered as highly ranked evidence .…”