Atypical antipsychotics in the treatment of bipolar disorder

Impact of initiation of asenapine on patterns of utilization and cost of healthcare resources associated with the treatment of bipolar I disorder

OBJECTIVE

To assess the impact of initiation of asenapine on "real-world" levels of utilization and cost of healthcare services for the treatment of bipolar I disorder (BPD) in the US.

METHODS

Using two large US healthcare claims databases that collectively included commercially insured patients aged < 65 years and Medicare enrollees, this study identified all adults (≥ 18 years) with evidence of BPD who began therapy with asenapine between 2009-2012. The date of the earliest claim for asenapine during this period was deemed the 'index date', and patients without continuous enrollment for the 6-month periods before and after this date were excluded ('pre-index' and 'post-index', respectively). Healthcare claims with a BPD diagnosis, plus psychiatric medications and the costs thereof (2012 dollars) were deemed 'BPD-related'. Differences in BPD-related utilization and cost of healthcare services were compared between the pre- and post-index periods.

RESULTS

A total of 1403 patients met all selection criteria; the mean age was 42.8 years and 70.6% were women. Relative to pre-index, significant decreases were noted in post-index use of BPD-related healthcare services, most notably admissions (from 24.0% to 12.3% during the post-index period) and emergency department visits (from 4.6% to 2.6%) (both p < 0.05). While pharmacy costs increased, mean total post-index BPD-related healthcare costs were $979 lower than pre-index ($5002 vs $5981; p < 0.05), primarily due to the decrease in BPD-related admissions.

CONCLUSIONS

Relative to the 6-month period beforehand, levels of utilization of BPD-related healthcare services and costs decreased during the 6-month period immediately following initiation of asenapine therapy.

Safety and tolerability of quetiapine in the treatment of acute mania in bipolar disorder

OBJECTIVE

To review the safety/tolerability of quetiapine in four placebo-controlled studies in patients with bipolar I disorder experiencing acute mania.

METHODS

Four double-blind, placebo-controlled studies evaluated quetiapine monotherapy (12 weeks) or quetiapine in combination with lithium (mean serum concentration 0.76 mEq/L) or divalproex (mean serum concentration 68.6 microg/mL) (Li/DVP) (3 and 6 weeks) in patients with acute mania. Pooled data from the two monotherapy studies and the two combination therapy studies have been evaluated in the analysis presented here. Adverse event reporting, Simpson Angus Scale (SAS), and Barnes Akathisia Rating Scale (BARS) scores were recorded.

RESULTS

Most adverse events were mild to moderate. Common adverse events (> or = 5% and at least twice the placebo rate) with quetiapine monotherapy and combination therapy were somnolence, dry mouth, weight gain, dizziness, asthenia, pharyngitis, and postural hypotension. Treatment-related discontinuations due to adverse events were not significantly different between quetiapine and placebo, nor was the incidence of extrapyramidal symptoms (including akathisia) (quetiapine monotherapy 12.9% vs placebo 13.1%; combination therapy 21.4% vs placebo 19.2%). Mean change from baseline to endpoint in SAS and BARS scores was not significantly different between groups. Mean weight change at treatment end with quetiapine compared with placebo was +1.8 vs -0.15 kg in monotherapy; and +1.97 vs +0.27 kg with combination therapy. No patients discontinued due to weight gain. The effect of quetiapine monotherapy on serum prolactin levels was no different from placebo.

CONCLUSIONS

Quetiapine monotherapy and combination therapy were well tolerated in the treatment of acute mania.

Emerging experimental therapeutics for bipolar disorder: insights from the molecular and cellular actions of current mood stabilizers

Bipolar disorder afflicts approximately 1-3% of both men and women, and is coincident with major economic, societal, medical, and interpersonal consequences. Current mediations used for its treatment are associated with variable rates of efficacy and often intolerable side effects. While preclinical and clinical knowledge in the neurosciences has expanded at a tremendous rate, recent years have seen no major breakthroughs in the development of novel types of treatment for bipolar disorder. We review here approaches to develop novel treatments specifically for bipolar disorder. Deliberate (ie not by serendipity) treatments may come from one of two general mechanisms: (1) Understanding the mechanism of action of current medications and thereafter designing novel drugs that mimics these mechanism(s); (2) Basing medication development upon the hypothetical or proven underlying pathophysiology of bipolar disorder. In this review, we focus upon the first approach. Molecular and cellular targets of current mood stabilizers include lithium inhibitable enzymes where lithium competes for a magnesium binding site (inositol monophosphatase, inositol polyphosphate 1-phosphatase, glycogen synthase kinase-3 (GSK-3), fructose 1,6-bisphosphatase, bisphosphate nucleotidase, phosphoglucomutase), valproate inhibitable enzymes (succinate semialdehyde dehydrogenase, succinate semialdehyde reductase, histone deacetylase), targets of carbamazepine (sodium channels, adenosine receptors, adenylate cyclase), and signaling pathways regulated by multiple drugs of different classes (phosphoinositol/protein kinase C, cyclic AMP, arachidonic acid, neurotrophic pathways). While the task of developing novel medications for bipolar disorder is truly daunting, we are hopeful that understanding the mechanism of action of current mood stabilizers will ultimately lead clinical trials with more specific medications and thus better treatments those who suffer from this devastating illness.