Oxcarbazepine in the treatment of bipolar and schizoaffective disorders

Oxcarbazepine versus sodium valproate in treatment of acute mania: a double-blind randomized clinical trial

Oxcarbazepine as an anticonvulsant has been suggested as an effective drug in affective disorders. The present study was designed to compare the efficacy of oxcarbazepine and sodium valproate in the treatment of acute mania in the Iranian population. In a double-blind, randomized clinical trial, hospitalized bipolar patients in the acute manic phase who were admitted to Ibn-e-Sina psychiatric hospital in Mashhad city (north-eastern part of Iran) were enrolled. The diagnosis was confirmed using Structured Clinical Interview for DSM-IV-TR. Patients were then randomly allocated into two groups taking oxcarbazepine (900-2400 mg/day) and sodium valproate (about 20 mg/kg/day) for 6 weeks. Young Mania Rating Scale (YMRS), Clinical Global Impression Scale (CGI-S), and adverse effects of drugs were assessed at baseline and after 3 and 6 weeks. Mania symptoms based on mean scores of YMRS and CGI-S significantly decreased from baseline to endpoint in both treatments (P < 0.01). However, there was no significant difference between the two groups in terms of reduction of symptoms during times (P = 0.715 and P = 0.446, respectively) and adverse events (P > 0.05). This study confirmed the previous findings that indicate the efficacy of oxcarbazepine as same as sodium valproate. Moreover, its adverse effects resemble sodium valproate in the treatment of acutely manic patients.

Use and safety of antiepileptic drugs in psychiatric inpatients-data from the AMSP study

The psychiatric utilization patterns and risks of antiepileptic drugs (AEDs) were assessed by using data from the drug safety programme Arzneimittelsicherheit in der Psychiatrie over the time period 1993-2013. In a total of 432,215 patients, the main indications for AED use were acute mania, schizoaffective disorder, and schizophrenic and organic psychoses. Valproic acid (VPA) was the most common substance across all of those groups, reaching administration rates of up to 50% since 2005, at which time carbamazepine (CBZ) administration consistently dropped below a rate of 10%. Lamotrigine (LTG) and pregabalin (PGB) increased in relevance after 2005 and 2010, respectively (with administration rates of up to 9%), whereas oxcarbazepine (OXC) was least prevalent (<3%). The mean rates of severe adverse drug reactions (ADRs) ranged from 6 cases per 1000 patients treated (VPA) to 19/1000 (OXC) and were significantly lower with treatment with VPA compared to OXC and CBZ. Hyponatremia was the leading ADR during treatment with OXC; severe allergic skin reactions were most often observed during treatment with CBZ and LTG, and severe oedema was most common during treatment with PGB. Severe hyponatremia induced by OXC was observed significantly more often in female patients than in male patients.

Targeting astrocytes in bipolar disorder

Astrocytes are homeostatic cells of the central nervous system, which are critical for development and maintenance of synaptic transmission and hence of synaptically connected neuronal ensembles. Astrocytic densities are reduced in bipolar disorder, and therefore deficient astroglial function may contribute to overall disbalance in neurotransmission and to pathological evolution. Classical anti-bipolar drugs (lithium salts, valproic acid and carbamazepine) affect expression of astroglial genes and modify astroglial signalling and homeostatic cascades. Many effects of both antidepressant and anti-bipolar drugs are exerted through regulation of glutamate homeostasis and glutamatergic transmission, through K(+) buffering, through regulation of calcium-dependent phospholipase A2 (that controls metabolism of arachidonic acid) or through Ca(2+) homeostatic and signalling pathways. Sometimes anti-depressant and anti-bipolar drugs exert opposite effects, and some effects on gene expression in drug treated animals are opposite in neurones vs. astrocytes. Changes in the intracellular pH induced by anti-bipolar drugs affect uptake of myo-inositol and thereby signalling via inositoltrisphosphate (InsP3), this being in accord with one of the main theories of mechanism of action for these drugs.

Pharmacological management of bipolar depression: acute treatment, maintenance, and prophylaxis

Although the most distinctive clinical feature of bipolar disorder is the pathologically elevated mood, it does not usually constitute the prevalent mood state of bipolar illness. The majority of patients with bipolar disorder spend much more time in depressive episodes, including subsyndromal depressive symptoms, and bipolar depression accounts for the largest part of the morbidity and mortality of the illness. The pharmacological treatment of bipolar depression mostly consists of combinations of at least two drugs, including mood stabilizers (lithium and anticonvulsants), atypical antipsychotics, and antidepressants. Antidepressants are the most frequently prescribed drugs, but recommendations from evidence-based guidelines are not conclusive and do not overtly support their use. Among antidepressants, best evidence exists for fluoxetine, but in combination with olanzapine. Although some guidelines recommend the use of selective serotonin reuptake inhibitors or bupropion in combination with antimanic agents as first-choice treatment, others do not, based on the available evidence. Among anticonvulsants, the use of lamotrigine is overall recommended as a first-line choice, but acute monotherapy studies have failed. Valproate is generally mentioned as a second-line treatment. Lithium monotherapy is also suggested by most guidelines as a first-line treatment, but its efficacy in acute use is not totally clear. Amongst atypical antipsychotics, quetiapine, in monotherapy or as adjunctive treatment, is recommended by most guidelines as a first-line choice. Olanzapine monotherapy is also suggested by some guidelines and is approved in Japan. Armodafinil, pramipexole, ketamine, and lurasidone are recent proposals. Long-term treatment in bipolar disorder is strongly recommended, but guidelines do not recommend the use of antidepressants as a maintenance treatment. Lithium, lamotrigine, valproate, olanzapine, quetiapine, and aripiprazole are the recommended first-line maintenance options.

Predictive animal models of mania: hits, misses and future directions

Mania has long been recognized as aberrant behaviour indicative of mental illness. Manic states include a variety of complex and multifaceted symptoms that challenge clear clinical distinctions. Symptoms include over-activity, hypersexuality, irritability and reduced need for sleep, with cognitive deficits recently linked to functional outcome. Current treatments have arisen through serendipity or from other disorders. Hence, treatments are not efficacious for all patients, and there is an urgent need to develop targeted therapeutics. Part of the drug discovery process is the assessment of therapeutics in animal models. Here we review pharmacological, environmental and genetic manipulations developed to test the efficacy of therapeutics in animal models of mania. The merits of these models are discussed in terms of the manipulation used and the facet of mania measured. Moreover, the predictive validity of these models is discussed in the context of differentiating drugs that succeed or fail to meet criteria as approved mania treatments. The multifaceted symptomatology of mania has not been reflected in the majority of animal models, where locomotor activity remains the primary measure. This approach has resulted in numerous false positives for putative treatments. Recent work highlights the need to utilize multivariate strategies to enable comprehensive assessment of affective and cognitive dysfunction. Advances in therapeutic treatment may depend on novel models developed with an integrated approach that includes: (i) a comprehensive battery of tests for different aspects of mania, (ii) utilization of genetic information to establish aetiological validity and (iii) objective quantification of patient behaviour with translational cross-species paradigms.

Therapeutic Drug Monitoring of the Newer Anti-Epilepsy Medications

In the past twenty years, 14 new antiepileptic drugs have been approved for use in the United States and/or Europe. These drugs are eslicarbazepine acetate, felbamate, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, pregabalin, rufinamide, stiripentol, tiagabine, topiramate, vigabatrin and zonisamide. In general, the clinical utility of therapeutic drug monitoring has not been established in clinical trials for these new anticonvulsants, and clear guidelines for drug monitoring have yet to be defined. The antiepileptic drugs with the strongest justifications for drug monitoring are lamotrigine, oxcarbazepine, stiripentol, and zonisamide. Stiripentol and tiagabine are strongly protein bound and are candidates for free drug monitoring. Therapeutic drug monitoring has lower utility for gabapentin, pregabalin, and vigabatrin. Measurement of salivary drug concentrations has potential utility for therapeutic drug monitoring of lamotrigine, levetiracetam, and topiramate. Therapeutic drug monitoring of the new antiepileptic drugs will be discussed in managing patients with epilepsy.

Therapeutic Drug Monitoring of the Newer Anti-Epilepsy Medications

In the past twenty years, 14 new antiepileptic drugs have been approved for use in the United States and/or Europe. These drugs are eslicarbazepine acetate, felbamate, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, pregabalin, rufinamide, stiripentol, tiagabine, topiramate, vigabatrin and zonisamide. In general, the clinical utility of therapeutic drug monitoring has not been established in clinical trials for these new anticonvulsants, and clear guidelines for drug monitoring have yet to be defined. The antiepileptic drugs with the strongest justifications for drug monitoring are lamotrigine, oxcarbazepine, stiripentol, and zonisamide. Stiripentol and tiagabine are strongly protein bound and are candidates for free drug monitoring. Therapeutic drug monitoring has lower utility for gabapentin, pregabalin, and vigabatrin. Measurement of salivary drug concentrations has potential utility for therapeutic drug monitoring of lamotrigine, levetiracetam, and topiramate. Therapeutic drug monitoring of the new antiepileptic drugs will be discussed in managing patients with epilepsy.

Anticonvulsants in bipolar disorder

Anticonvulsant drugs are widely used in psychiatric indications. This includes alcohol and benzodiazepine withdrawal symptoms, panic and anxiety disorders, dementia, schizophrenia, and to some extent personality disorders. Besides pain syndromes, their main domain outside epilepsy, however, is bipolar disorder. Carbamazepine, valproate, and lamotrigine are meanwhile recognized mood stabilizers, but several other antiepileptic drugs have also been tried out with diverging or inconclusive results. Understanding the mechanisms of action and identifying similarities between anticonvulsants effective in bipolar disorder may also enhance our understanding of the underlying pathophysiology of the disorder.

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.

Acute and long-term treatment of mania

The treatment of mania starts with a correct diagnosis and elementary measures to prevent risks for the patient, relatives, and others. Sometimes, compulsory admission and treatment may be required for a few days. Patients with psychotic or mixed mania may be more difficult to treat. At the present time, there is solid evidence supporting the use of lithium, the anticonvulsants valproate and carbamazepine, and the antipsychotics chlorpromazine, haloperidol, risperidone, olanzapine, quetiapine, ziprasidone, aripiprazole, and asenapine in acute mania, and some evidence supporting the use of clozapine or electroconvulsive therapy in treatment-refractory cases. However, in clinical practice, combination therapy is the rule rather than the exception. The treatment of acute mania deserves a long-term view, and the evidence base for some treatments may be stronger than for others. When taking decisions about treatment, tolerability should also be a major concern, as differences in safety and tolerability may exceed differences in efficacy for most compounds. Psychoeducation of patients and caregivers is a powerful tool that should be used in combination with medication for optimal long-term outcome. Functional recovery should be the ultimate goal.

A double-blind, randomized, placebo-controlled prophylaxis trial of oxcarbazepine as adjunctive treatment to lithium in the long-term treatment of bipolar I and II disorder

We evaluated the prophylactic efficacy and the long-term tolerability of oxcarbazepine administration in the treatment of bipolar I and II disorder as an adjunctive therapy to lithium. We conducted a 52-wk, double-blind, randomized, placebo-controlled, parallel-group, multicentre, clinical trial. Bipolar I and II DSM-IV outpatients, having had two or more episodes in the last year, but currently being in remission, were randomly assigned on a 1:1 ratio to oxcarbazepine (n=26) or placebo (n=29) as adjuncts to ongoing treatment with lithium. The primary efficacy variable was the length of the remission period assessed by means of the Young Mania Rating Scale (YMRS) and Montgomery-Asberg Depression Rating Scale (MADRS). Other assessments were the Clinical Global Impression (CGI-BP-M), functional activity (GAF), anxiety (HAMA) and impulsiveness (BIS-11). The average time until first recurrence of any type was 19.2+/-13.9 wk and 18.6+/-17.0 wk for oxcarbazepine and placebo respectively (p=0.315). Ten (38.46%) patients had a recurrence of any kind in the oxcarbazepine group vs. 17 (58.62%) in the placebo group (p=0.1354). There was a trend for depressive episodes being less likely in the oxcarbazepine group compared to the placebo group (11.54% and 31.03% respectively, p=0.085), and for better functionality with the GAF (p=0.074). Impulsivity was significantly better prevented by oxcarbazepine (p=0.0443). Overall, oxcarbazepine was well tolerated. This pilot, randomized clinical trial, suggests that oxcarbazepine might have some prophylactic efficacy with regards to impulsivity and perhaps mood episodes in patients taking lithium, although further, adequately powered controlled trials are needed to confirm these findings.

Oxcarbazepine in the maintenance treatment of bipolar disorder

BACKGROUND

Some studies have suggested that oxcarbazepine has a role in preventing episode recurrence in bipolar affective disorder. This review attempted to investigate the existing evidence from randomised controlled trials for its use in the maintenance treatment of this illness.

OBJECTIVES

To review the efficacy of oxcarbazepine, relative to placebo and other agents, in the prevention of affective episodes of bipolar affective disorder. The efficacy of oxcarbazepine was considered in terms of episode recurrence, general and social functioning. Adverse effects, overall acceptability to participants and mortality were also considered.

SEARCH STRATEGY

CCDANCTR-Studies and CCDANCTR-References were searched on 7/11/2007. Medline, CENTRAL, EMBASE and PsycINFO were searched in March 2007. Specialist journals and conference proceedings were handsearched. Reference lists of relevant papers and major textbooks of affective disorder were checked. Authors, experts in the field and pharmaceutical companies were contacted requesting information on published or unpublished trials.

SELECTION CRITERIA

Randomised controlled trials comparing oxcarbazepine with placebo or alternative agents, where the stated intent of intervention was the maintenance treatment of bipolar affective disorder were sought. Participants with bipolar disorder, male and female, of all ages, were included.

DATA COLLECTION AND ANALYSIS

Data were extracted from the original reports individually by two review authors. The methodological quality of included studies was assessed individually by two review authors. The main outcomes were the efficacy of oxcarbazepine maintenance treatment in preventing or attenuating further episodes of bipolar affective disorder (including its efficacy in rapid cycling disorder), the acceptability of oxcarbazepine treatment to participants, the prevalence of side-effects, and mortality, if any, on oxcarbazepine treatment. Where appropriate, data concerning outcome measures and adverse effects were to be extracted from the studies and analysed using Review Manager software.

MAIN RESULTS

Two randomised controlled trials were found that met the methodological criteria for inclusion in the review. However, they did not report data with sufficient clarity to allow their confident extraction for inclusion in the meta-analysis. Findings from the two studies were presented descriptively.

AUTHORS' CONCLUSIONS

There is an insufficient methodologically rigorous evidence base to provide guidance on the use of oxcarbazepine in the maintenance treatment of bipolar disorder. Given the need for more efficacious therapeutic agents, there is a need for good quality randomised controlled trials examining the therapeutic potential of this and related agents in bipolar disorder.