Aripiprazole: pharmacology and evidence in bipolar disorder

Case report: rTMS in combination with aripiprazole and sodium valproate for the maintenance treatment of rapid cycling bipolar disorder

As a safe neuromodulation therapy, rTMS is applied to treat a variety of psychiatric and neurological disorders. Additionally, both aripiprazole and sodium valproate are effective in the treatment of rapid cycling bipolar disorder. This case reports a female patient with a 17-year history of bipolar disorder who developed rapid-circulation bipolar disorder 5 years prior to presentation. After combined treatment with rTMS, aripiprazole, and sodium valproate, the patient’s mood remained stable and she was able to live and work normally.

Understanding variability in the pharmacokinetics of atypical antipsychotics - focus on clozapine, olanzapine and aripiprazole population models

Antipsychotic medicines are widely used for the management of psychotic symptoms regardless of the underlying diagnosis. Most atypical antipsychotics undergo extensive metabolism prior to excretion. Various factors may influence their pharmacokinetics, particularly elimination, leading to highly variable drug concentrations between individual patients following the same dosing regimen. Population pharmacokinetic approach, based on nonlinear mixed effects modeling, is a useful tool to identify covariates explaining pharmacokinetic variability, as well as to characterize and distinguish unexplained residual and between-subject (interindividual) variability. In addition, this approach allows the use of both sparsely and intensively sampled data. In this paper, we reviewed the pharmacokinetic characteristics of clozapine, olanzapine and aripiprazole, focusing on a population modeling approach. In particular, models based on a nonlinear mixed effects approach performed by NONMEM^® software in order to identify and quantify sources of pharmacokinetic variability are presented. Population models were identified through systematic searches of PubMed and sixteen studies were selected. Some of the factors identified that significantly contribute to variability in elimination among clozapine, olanzapine, and aripiprazole are demographic characteristics, body weight, genetic polymorphism, smoking and in some cases drug interactions. Scientific research based on pharmacometric modeling is useful to further characterize sources of variability and their combined effect.

The safety and tolerability of aripiprazole once-monthly as maintenance treatment for bipolar I disorder: A double-blind, placebo-controlled, randomized withdrawal study

BACKGROUND

Aripiprazole once-monthly 400 mg (AOM 400), an atypical long-acting injectable antipsychotic, has demonstrated efficacy and safety in maintenance treatment of bipolar I disorder (BP-I). We further assess safety and tolerability and characterize adverse events (AEs) across the duration of aripiprazole exposure.

METHODS

Patients with BP-I were stabilized on oral aripiprazole (2-8 weeks), AOM 400 (12-28 weeks), followed by 1:1 randomization of patients meeting stability criteria to a 52-week, double-blind, placebo-controlled withdrawal phase. Treatment-emergent AEs (TEAEs) were collected across study phases. AEs were counted in a phase if they were drug-related and continued from the baseline of that phase. A separate analysis on new-onset akathisia was conducted.

RESULTS

Among TEAEs occurring in ≥10% of patients during all study phases were akathisia (23.3%) and weight increased (10.6%). Median time to akathisia onset was 20 days after starting oral aripiprazole; median duration was 29 days for the first occurrence; 21/168 patients (12.5%) reporting akathisia experienced >1 episode. Episodes of new-onset akathisia decreased over time, with few events reported in the randomized phase. Weight gain was minimal with oral aripiprazole, generally starting within 3 months after the first AOM 400 injection, and appearing to plateau at 36 weeks. The mean weight gain within any study phase was ≤1.0 kg. Potentially clinically significant changes in metabolic parameters were uncommon.

LIMITATIONS

Patients on placebo had AOM 400 exposure before randomization.

CONCLUSION

These findings suggest that AEs with AOM 400 treatment were time-limited and support AOM 400 as a well-tolerated maintenance treatment of BP-I.

Maintenance treatment in bipolar disorder: a focus on aripiprazole

Bipolar disorders (BD) are chronic medical syndromes heterogeneous in phenomenology, pathophysiology and treatment. The longitudinal course of bipolar disorders is often characterized by nonrecovery, subsyndromal symptoms, enduring cognitive deficits and impairment in psychosocial function. The risk for premature mortality from unnatural (e.g., suicide) as well as natural causes (e.g., cardiovascular disease) is significantly higher than the general population. The therapeutic objectives of maintenance therapy are to prevent relapse/recurrence, reduce the risk for premature mortality, promote functional restoration and enhance quality of life. A chronic disease management model, which includes pharmacologic and manual-based psychosocial interventions as paradigmatic components, provides a framework for best practice and optimal patient outcome. This article provides a succinct review of treatments approved by the US FDA for maintenance in bipolar disorders, with a focus on the most recently approved atypical antipsychotic, aripiprazole.

When to start aripiprazole therapy in patients with bipolar mania

Aripiprazole is a third generation atypical antipsychotic with compelling evidence as a highly effective treatment option in the management of acute manic and mixed episodes of bipolar I disorders. It has a unique mode of action, acting as a partial agonist at dopamine D2 and D3, and serotonin 5-HT1A; and exhibiting antagonistic action at the 5-HT2A and H1 receptors. Overall, it has a favorable safety and tolerability profile, with low potential for clinically significant weight gain and metabolic effects, especially compared to other well-established treatments. It also has a superior tolerability profile when used as maintenance treatment. Side effects like headache, insomnia, and extrapyramidal side effects (EPSEs), such as tremor and akathisia may be treatment limiting in some cases. It is efficacious in both acute mania and mixed states, and in the long-term prevention of manic relapses. Aripiprazole therefore, is a significant player in the current portfolio of anti-manic pharmacological treatments. The data sources for this article are from EMBASE, MEDLINE, and the clinical trial database searches for all the literature published between January 2003 and September 2013. The key search terms were "aripiprazole" combined with "bipolar disorder", "mania", "antipsychotics", "mood stabilizer", "randomized controlled trial", and "pharmacology". Abstracts and proceedings from national and international psychiatric meetings were also reviewed, along with reviews of the reference lists of relevant articles.

Pharmacokinetics, tolerability and safety of aripiprazole once-monthly in adult schizophrenia: an open-label, parallel-arm, multiple-dose study

This 24-week, open-label, Phase Ib, parallel-arm, multiple-dose trial assessed the pharmacokinetics, safety and tolerability of a once-monthly injection of aripiprazole (aripiprazole once-monthly) in 41 subjects with schizophrenia. The objective was to determine if aripiprazole plasma concentrations (at doses of 200, 300 and 400mg) were within the therapeutic range observed for the oral tablet (10-30 mg). Completion rates were 36.4% (n=4/11), 50.0% (n=8/16) and 71.4% (n=10/14) for the 200mg, 300 mg and 400mg groups, respectively. Patients were stabilized on oral aripiprazole (10mg/day) before the first injection and received oral aripiprazole (10mg/day) concomitantly with the first dose of aripiprazole once-monthly for 14 days. Administration of aripiprazole once-monthly at doses of 300 and 400mg provided sustained mean aripiprazole plasma concentrations comparable with the concentration range observed following multiple consecutive daily doses of oral aripiprazole. In contrast, plasma concentrations following administration of aripiprazole once-monthly at a dose of 200mg were below the therapeutic range and pharmacokinetic parameters were not proportional to the administered dose compared with the 300 mg and 400mg doses. Treatment with aripiprazole once-monthly, at any dose, did not result in any clinically meaningful changes from baseline in extrapyramidal symptom scales, clinical laboratory tests, vital signs, or electrocardiogram parameters. The most common treatment-emergent adverse events were vomiting (13.3%, 300 mg; 14.3%, 400mg), injection site pain (28.6%, 400mg), upper respiratory tract infection (10%, 200mg; 6.7% 300 mg; 14.3%, 400mg) and tremor (6.7%, 300 mg; 21.4%, 400mg). In conclusion, aripiprazole once-monthly at doses of 300 and 400mg is a viable formulation for treatment of adults with schizophrenia.

Aripiprazole in patients with bipolar mania and beyond: an update of practical guidance

BACKGROUND

Aripiprazole is an atypical antipsychotic with a pharmacological and clinical profile distinct from other atypical antipsychotics.

SCOPE

A European multidisciplinary advisory panel of university-based experts in bipolar disorders convened in April 2010 to review new clinical guidelines for the management of mania and the role of aripiprazole in its treatment. This report describes the consensus reached on how best to use aripiprazole in the treatment of mania.

FINDINGS

Current guidelines recommending aripiprazole for first-line treatment of mania have not generally translated to clinical practice. The panel agreed that clinicians may not feel sufficiently knowledgeable on how to use aripiprazole effectively in mania, and that the perception that aripiprazole is less sedating than other antipschotics may hamper its use. There was consensus about the importance of ensuring that clinicians understood the distinction between antimanic efficacy and sedation. Most acutely manic patients may require night-time sedation, but continuous daytime sedation is not necessarily indicated and may interfere with long-term compliance. If sedation is necessary, guidelines recommend the use of adjunctive benzodiazepines only for a short-time.

CONCLUSIONS

Clinical practice guidelines widely recommend aripiprazole as a first-line treatment for mania. Although clinical trials may not represent all patient subpopulations, they show that aripiprazole is well tolerated and has a long-term stabilizing potential. The successful use of aripiprazole rests on using the appropriate initial dose, titrating and adjusting the dose as needed and using appropriate concomitant medication to minimize any short-term adverse events. Low incidence of sedation makes aripiprazole a reasonable long-term treatment choice. If short-term sedation is required an adjunctive sedative agent can be added and removed when no longer needed. Clinical considerations should influence treatment choice, and a better distinction between sedation and antimanic effects should be an educational target aimed to overcome potential barriers for using non-sedative antimanic agents such as aripiprazole.

Aripiprazole monotherapy in the treatment of bipolar disorder: a meta-analysis

INTRODUCTION

Aripiprazole is approved for the acute and maintenance treatment of manic and mixed episodes associated with bipolar I disorder. The aim of the present work was to review and meta-analyze the findings of all the available randomized double-blind controlled trials (RCTs) on the efficacy of aripiprazole in the treatment of bipolar disorder.

MATERIAL AND METHODS

Aripiprazole RCTs were identified with a systematic search of MEDLINE and repositories. Standard meta-analytic techniques were applied.

RESULTS

Two thousand three hundred and three patients took part in the aripiprazole acute mania RCTs. At week 3 the pooled aripiprazole vs. placebo effect size was 0.34 and the NNT was 6 for response and 14 for remission. On average, response started at day 3. Suicide rates were negligible for all groups in mania but they were not reported in the acute depression trials. The meta-analysis of acute bipolar depression RCTs revealed a significant difference at week 8 with a weak effect size equal to 0.17. The analysis of maintenance data suggest that the median survival time for the aripiprazole group was not evaluable (very long), while the median survival time for placebo was 118-203 days depending on the clinical subpopulation.

DISCUSSION

The current meta-analysis supports the usefulness of aripiprazole during all phases of bipolar illness. Its effect against acute bipolar depression is weak and the efficacy during the maintenance phase is proven only against new manic episodes in patients with an index manic episode who had previously responded to aripiprazole during the acute phase.

Aripiprazole in the maintenance treatment of bipolar disorder: a critical review of the evidence and its dissemination into the scientific literature

BACKGROUND

Aripiprazole, a second-generation antipsychotic medication, has been increasingly used in the maintenance treatment of bipolar disorder and received approval from the U.S. Food and Drug Administration for this indication in 2005. Given its widespread use, we sought to critically review the evidence supporting the use of aripiprazole in the maintenance treatment of bipolar disorder and examine how that evidence has been disseminated in the scientific literature.

METHODS AND FINDINGS

We systematically searched multiple databases to identify double-blind, randomized controlled trials of aripiprazole for the maintenance treatment of bipolar disorder while excluding other types of studies, such as open-label, acute, and adjunctive studies. We then used a citation search to identify articles that cited these trials and rated the quality of their citations. Our evidence search protocol identified only two publications, both describing the results of a single trial conducted by Keck et al., which met criteria for inclusion in this review. We describe four issues that limit the interpretation of that trial as supporting the use of aripiprazole for bipolar maintenance: (1) insufficient duration to demonstrate maintenance efficacy; (2) limited generalizability due to its enriched sample; (3) possible conflation of iatrogenic adverse effects of abrupt medication discontinuation with beneficial effects of treatment; and (4) a low overall completion rate. Our citation search protocol yielded 80 publications that cited the Keck et al. trial in discussing the use of aripiprazole for bipolar maintenance. Of these, only 24 (30%) mentioned adverse events reported and four (5%) mentioned study limitations.

CONCLUSIONS

A single trial by Keck et al. represents the entirety of the literature on the use of aripiprazole for the maintenance treatment of bipolar disorder. Although careful review identifies four critical limitations to the trial's interpretation and overall utility, the trial has been uncritically cited in the subsequent scientific literature. Please see later in the article for the Editors' Summary.

Aripiprazole for the maintenance treatment of bipolar disorder: a review of available evidence

We aimed to review and synthesize results reporting on the maintenance efficacy of Aripiprazole in adults with bipolar I disorder. Aripiprazole is FDA approved for the acute and maintenance treatment of bipolar I disorder. Aripiprazole's efficacy during the long-term treatment of bipolar disorder is supported by extension of acute phase studies and long-term (ie, 100-week) double-blind placebo controlled recurrence prevention registration trials. Aripiprazole is not established as efficacious in the acute or maintenance treatment of bipolar depression. Moreover, aripiprazole's efficacy during the acute or maintenance phase of bipolar II disorder has not been sufficiently studied. Aripiprazole has a relatively lower hazard for metabolic disruption and change in body composition when compared to other atypical agents (eg, olanzapine, quetiapine). Moreover, aripiprazole has minimal propensity for sedation, somnolence and prolactin elevation. Aripiprazole is associated with extrapyramidal side effects, notably akathisia, which in most cases is not severe or treatment limiting. Future research vistas are to explore aripiprazole's efficacy in bipolar subgroups; recurrence prevention of bipolar depression; and in combination with other mood stabilizing agents.

Tardive dyskinesia and other movement disorders secondary to aripiprazole

The objective of this report is to draw attention to tardive dyskinesia (TD) caused by aripiprazole, a third generation antipsychotic. TD has been traditionally attributed to typical (first-generation) antipsychotics, but other dopamine receptor blocking drugs and atypical (second- and third-generation) neuroleptics are emerging as an important cause of TD. We reviewed the medical records of patients with TD seen at the Baylor College of Medicine Movement Disorders Clinic between 2002 and 2010 to identify patients with TD associated with aripiprazole. Among 236 patients with TD seen over the specified period, 8 (3.4%) were found to have aripiprazole-associated TD. In 5 patients, TD occurred after exclusive exposure to aripiprazole. The mean age at onset was 55.8 ± 14.8 years with a female predominance. The average duration of treatment with aripiprazole was 18.4 ± 26.4 months. Oro-bucco-lingual stereotypy was seen in all patients. In most patients, TD did not spontaneously improve after stopping aripiprazole. Of the 5 patients treated with tetrabenazine, 4 improved during follow-up. Although aripiprazole, a third generation antipsychotic, has been promoted to have a low risk of TD, the drug accounts for about 3.5% of patients with TD evaluated in a movement disorders clinic. This largest reported series draws attention to the growing incidence of TD and other drug-induced movement disorders associated with "atypical antipsychotics."

Evaluation of akathisia in patients with schizophrenia, schizoaffective disorder, or bipolar I disorder: a post hoc analysis of pooled data from short- and long-term aripiprazole trials

The objective of this article is to assess the clinical characteristics of akathisia in patients with schizophrenia, schizoaffective disorder, or bipolar I disorder receiving aripiprazole, haloperidol, olanzapine, or placebo. We conducted post hoc analyses of pooled safety data from trials in patients with schizophrenia, schizoaffective disorder, and bipolar I disorder. Outcome measures included the incidence of akathisia, time to onset, duration, severity, and discontinuation due to akathisia, concomitant use of benzodiazepines and/or anticholinergics, Barnes Akathisia Rating Scale (BARS) scores, and the correlation between antipsychotic efficacy and akathisia. The results for schizophrenia and schizoaffective disorder were as follows: akathisia in 9% of aripiprazole- and 6% of placebo-treated patients; 12.5% of aripiprazole- versus 24% of haloperidol-treated patients; 11% of aripiprazole- versus 6% of olanzapine-treated patients. Bipolar I disorder: akathisia in 18% of aripiprazole- and 5% of placebo-treated patients. The clinical characteristics of akathisia were similar between each data set, regardless of disease. Akathisia was generally mild-to-moderate in severity. Discontinuation due to akathisia was low in both the schizophrenia trials (aripiprazole 0.3%; placebo 0%; aripiprazole 0.9%; haloperidol 2.3%; aripiprazole 1.2%; olanzapine 0.2%) and the bipolar trials (aripiprazole 2.3%; placebo 0%). Treatment-emergent akathisia was not associated with a poorer clinical response. In conclusion, akathisia with aripiprazole occurred early in treatment, was mild-to-moderate in severity, led to few study discontinuations, and did not compromise therapeutic efficacy.

Treatment of psychotic symptoms in bipolar disorder with aripiprazole monotherapy: a meta-analysis

BACKGROUND

We present a systematic review and meta-analysis of the available clinical trials concerning the usefulness of aripiprazole in the treatment of the psychotic symptoms in bipolar disorder.

METHODS

A systematic MEDLINE and repository search concerning clinical trials for aripiprazole in bipolar disorder was conducted.

RESULTS

The meta-analysis of four randomised controlled trials (RCTs) on acute mania suggests that the effect size of aripiprazole versus placebo was equal to 0.14 but a more reliable and accurate estimation is 0.18 for the total Positive and Negative Syndrome Scale (PANSS) score. The effect was higher for the PANSS-positive subscale (0.28), PANSS-hostility subscale (0.24) and PANSS-cognitive subscale (0.20), and lower for the PANSS-negative subscale (0.12). No data on the depressive phase of bipolar illness exist, while there are some data in favour of aripiprazole concerning the maintenance phase, where at week 26 all except the total PANSS score showed a significant superiority of aripiprazole over placebo (d = 0.28 for positive, d = 0.38 for the cognitive and d = 0.71 for the hostility subscales) and at week 100 the results were similar (d = 0.42, 0.63 and 0.48, respectively).

CONCLUSION

The data analysed for the current study support the usefulness of aripiprazole against psychotic symptoms during the acute manic and maintenance phases of bipolar illness.

Efficacy and safety of aripiprazole in the treatment of bipolar disorder: a systematic review

BACKGROUND

The current article is a systematic review concerning the efficacy and safety of aripiprazole in the treatment of bipolar disorder.

METHODS

A systematic Medline and repositories search concerning the usefulness of aripiprazole in bipolar disorder was performed, with the combination of the words 'aripiprazole' and 'bipolar'.

RESULTS

The search returned 184 articles and was last updated on 15 April 2009. An additional search included repositories of clinical trials and previous systematic reviews specifically in order to trace unpublished trials. There were seven placebo-controlled randomised controlled trials (RCTs), six with comparator studies and one with add-on studies. They assessed the usefulness of aripiprazole in acute mania, acute bipolar depression and during the maintenance phase in comparison to placebo, lithium or haloperidol.

CONCLUSION

Aripiprazole appears effective for the treatment and prophylaxis against mania. The data on bipolar depression are so far negative, however there is a need for further study at lower dosages. The most frequent adverse effects are extrapyramidal signs and symptoms, especially akathisia, without any significant weight gain, hyperprolactinaemia or laboratory test changes.

Effect of aripiprazole on self-reported anhedonia in bipolar depressed patients

Some studies have suggested that aripiprazole might be a useful treatment for bipolar depression. There are no studies evaluating the effect of aripiprazole on anhedonia. In the present study, effects of aripiprazole were investigated under routine clinical conditions. Anhedonia was measured in patients with bipolar disorder type I (n=50) using the self-rated Snaith-Hamilton Pleasure Scale (SHAPS) and depression was assessed using the Montgomery-Asberg Depression Rating Scale. Anhedonia was present in 52% of all patients and was significantly reduced during treatment with aripiprazole. All patients completed the 16-week trial. Only 16% of patients experienced side effects (akathisia, headache). Future studies should investigate the specificity of anti-anhedonic and anti-depressant properties of aripiprazole in bipolar patients.

The World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the biological treatment of bipolar disorders: update 2009 on the treatment of acute mania

These updated guidelines are based on a first edition that was published in 2003, and have been edited and updated with the available scientific evidence until end of 2008. Their purpose is to supply a systematic overview of all scientific evidence pertaining to the treatment of acute mania in adults. The data used for these guidelines have been extracted from a MEDLINE and EMBASE search, from the clinical trial database clinicaltrials.gov, from recent proceedings of key conferences, and from various national and international treatment guidelines. Their scientific rigor was categorised into six levels of evidence (A-F). As these guidelines are intended for clinical use, the scientific evidence was finally asigned different grades of recommendation to ensure practicability.

Tolerability and pharmacokinetics of aripiprazole in children and adolescents with psychiatric disorders: an open-label, dose-escalation study

This multicenter, open-label, sequential-cohort, dose-escalation study explored the tolerability and pharmacokinetics (PK) of aripiprazole up to the maximum approved adult dose (30 mg/d) in children and adolescents (aged 10-17 years) preferentially with primary psychiatric diagnoses of a bipolar or schizophrenia spectrum disorder. During a dose-escalation phase, patients received aripiprazole for up to 12 days using forced titration to achieve doses of 20, 25, or 30 mg/d. In the subsequent fixed-dose phase, patients received the maximum dose for that cohort for an additional 14 days. Tolerability in each fixed-dose cohort was assessed by measures including evaluation of spontaneously reported adverse events (AEs) and vital signs. If 4 of 6 patients tolerated the maximum dose for the cohort, the dose was considered tolerated, and enrollment in the next dose level began. Of 21 enrolled patients, 17 completed the fixed-dose phase. Aripiprazole treatment was generally well tolerated, with criteria for tolerability met for all doses tested. All patients experienced at least 1 AE, none of which met the regulatory criteria for a serious AE. There were no deaths or clinically relevant changes in vital signs or weight. Aripiprazole PK seemed to be linear across the tested dose range and was comparable with previous PK observations in adults. This study provides information regarding the tolerability and PK of aripiprazole up to the maximum adult dose in children and adolescents. These data provided support for exploration of a 30-mg/d dose in child/adolescent schizophrenia and bipolar disorder.