Improved quality of life in patients with partial seizures after conversion to oxcarbazepine monotherapy

Current role of carbamazepine and oxcarbazepine in the management of epilepsy

Epilepsy is one of the most common neurological disorders, affecting approximately 50 million people worldwide. Despite a dramatic increase in treatment options over the past 30 years, it still ranks fourth in the world's disease burden. There are now close to 30 antiepileptic drugs (AEDs), with more than two thirds introduced to the market after carbamazepine (CBZ) and one third after its derivative, oxcarbazepine (OXC). Following the introduction of these newer AEDs, the role of CBZ and OXC in the therapeutic armamentarium for seizure control and effective epilepsy management needs to be reviewed. The main guidelines list both CBZ and OXC as first-line options or second-line alternatives for the treatment of focal-onset epilepsy and primary generalized tonic-clonic seizures. While evidence suggests that overall AEDs have similar efficacy, some newer AEDs may be better tolerated than CBZ. In line with this, there have been changes in treatment patterns, with many variations across different countries. However, CBZ remains among the two or three most prescribed drugs for focal epilepsy in many countries, and is widely used across Europe, Africa, South America, and Asia, where it represents a good compromise between cost, availability, and effectiveness. OXC is among the first-choice options for the initial treatment of focal-onset seizures in several countries, including the US and China, where the oral suspension is commonly prescribed. This review provides guidance on the optimal use of these two drugs in clinical practice, including in children, the elderly, and in pregnancy.

Health-related quality of life in patients treated with eslicarbazepine acetate monotherapy: Pooled analysis from two registered clinical trials

PURPOSE

While antiepileptic drug (AED) treatment effectiveness is traditionally assessed based on seizure frequency reduction (SFR), the overall value of AEDs in managing epilepsy and associated sequelae may be best assessed by how patients feel and function in terms of overall health-related quality of life (HRQoL). We conducted a pooled analysis of the Quality of Life in Epilepsy-31 (QOLIE-31) questionnaire from two phase 3 trials to explore the effect of response to conversion to eslicarbazepine acetate (ESL) monotherapy on HRQoL.

METHODS

Data were pooled from two multicenter, randomized, double-blind, historical control phase 3 trials examining conversion to ESL monotherapy in adults with inadequately controlled partial-onset seizures (POS). The relationship between HRQoL and ESL treatment response was examined through the analysis of week 18 QOLIE-31 scores between patients who met the SFR ≥50% threshold (responders) and patients with SFR <50% (nonresponders). The analysis was conducted in the efficacy population (intent-to-treat (ITT) patients who entered the AED taper/conversion period) and completer population (efficacy patients who completed the ESL monotherapy period) and was repeated using an SFR ≥75% threshold.

RESULTS

In the efficacy population, week 18 QOLIE-31 total score least squares mean (LSM) was significantly higher for responders with ≥50% SFR (LSM difference: 3.0; 95% confidence interval (CI): 0.2-5.8; p = 0.037) and with ≥75% SFR (LSM difference: 7.0; 95% CI: 3.6-10.3; p < 0.001) than nonresponders. In the completer population, overall quality of life (QoL) (LSM difference: 5.1; 95% CI: 1.5-8.6; p = 0.006) and social functioning (LSM difference: 5.4; 95% CI: 0.1-10.7; p = 0.046) were significantly higher for responders with ≥50% SFR than nonresponders, and all domain LSMs were higher for responders with ≥75% SFR (all p < 0.05) than nonresponders.

CONCLUSIONS

This analysis of data from the phase 3 trials demonstrated significantly higher HRQoL among ESL responders with SFR of ≥75% and also at the lower SFR threshold of ≥50% compared with nonresponders.

Decreased quality of life in children with hypothalamic hamartoma and treatment-resistant epilepsy

We evaluated health-related quality of life in patients with hypothalamic hamartoma, to see how it differs from that of children with more common neurologic disorders. We used the PedsQL 4.0, along with the Child Behavior Checklist, Hague Seizure Severity Scale, and Side Effects Scale, to evaluate presurgical patients with hypothalamic hamartoma and epilepsy (n = 21). The results were compared with those of age-matched cohorts with migraine (n = 19) and Benign Epilepsy with Central Temporal Spikes (n = 11). In comparison with the migraine group, the patients with hypothalamic hamartoma had decreased health-related quality of life across all domains of the PedsQL 4.0. Compared with the benign epilepsy group, the hypothalamic hamartoma cohort has a significantly lower score in School Function. Comorbid psychomotor retardation was predictive of lower quality of life. Research examining the efficacy of recently developed surgical treatments for hypothalamic hamartoma should include health-related quality of life as an outcome measure.

Psychosocial difficulties in people with epilepsy: a systematic review of literature from 2005 until 2010

The aims of this paper are to identify factors that influence the psychosocial difficulties (PSDs) that persons with epilepsy experience in their everyday life, to describe their onset and the way they evolve over time, and to analyze the determinants of changes over time and other related variables. Electronic databases were searched for studies published in English between January 2005 and May 2010, and information from thirteen studies was extracted. The most frequent PSDs found in people with epilepsy were depressive symptoms, memory functions, quality of life, anxiety, stigma, locus of control, cognitive functions in general, and emotional functions in general. It can be stated that patients' life areas are affected by cognitive, emotional, and psychological problems. However, the majority of studies focus on isolated PSDs or on the effects of a specific determinant in the course of epilepsy, leaving some gaps that could encourage further research.

Caregiver measures for seizure control, efficacy, and tolerability of antiepileptic drugs for childhood epilepsy: results of a preference survey

We sought to identify and quantify caregiver-defined characteristics of efficacy related to the perceived success of antiepileptic drug (AED) use. A 22-question survey was designed using physician input, focus groups, and clinical trial endpoints. Responses were pooled and analyzed with regard to seizure type and treatment, categorized as controlled (exposure to 1 AED), adjunctive (exposure to 2 AEDs), or refractory (exposure to ≥3 AEDs). Two hundred ninety-five surveys were completed: 109 (37%) controlled, 84 (28%) adjunctive, and 102 (35%) refractory. Seizure freedom and median seizure reduction >90% maintained for >1 year were reported as the most important indicators of medication efficacy by the majority of respondents. These measures were the same regardless of seizure type or treatment category. Our results demonstrate that current trial design may be inadequate to address the expectations of patients. Incorporating patient-defined AED efficacy measures may improve satisfaction and informed decision making regarding epilepsy treatment.

Use of the newer antiepileptic drugs in pediatric epilepsies

Children with epilepsy, particularly infants, differ from adults not only in the clinical manifestations of their seizures but also in the presence of unique electroencephalographic patterns, etiologies, and response to antiepileptic drugs (AEDs). There is a growing list of newer AEDs and nonpharmacologic therapies available to manage childhood epilepsy. These newer AEDs may not be overall more efficacious than the older drugs, but they do appear to be safer, better tolerated, and to have fewer drug-drug interactions. Selection of the AED for initial therapy must be based upon clinical judgment and patient-specific circumstances, such as the specific epilepsy syndrome being treated, anticipated duration of treatment, presence of comorbidities, ability to use certain formulations, and overall cost effectiveness. In some cases, seizures may be aggravated by the use of certain AEDs. Overall, oxcarbazepine is the first-line treatment for localization-related epilepsy with partial-onset seizures. For generalized epilepsies, the AED choice is highly dependent upon which specific syndrome is being treated. For generalized epilepsies with primarily absence seizures, lamotrigine is the AED of first choice. For mixed generalized epilepsies such as Lennox-Gastaut syndrome or juvenile myoclonic epilepsy, zonisamide or topiramate are the first-line agents. For infants with West syndrome, treatment is based upon the underlying etiology: vigabatrin for tuberous sclerosis; adrenocorticotropic hormone for children with no specific etiology uncovered (cryptogenic); and zonisamide for those with a severe symptomatic etiology other than tuberous sclerosis. Single drug therapy (monotherapy) is the goal of epilepsy treatment because this is associated with better compliance, fewer adverse effects, and lower cost. If the seizures prove intractable or adverse effects are encountered with the first AED, then a second monotherapy trial is undertaken. Once three appropriate medications at therapeutic doses have failed, other modalities should be considered, including epilepsy surgery, vagus nerve stimulation, and the ketogenic diet.

Measuring outcomes of treatment with antiepileptic drugs in clinical trials

Epilepsy often requires life-long treatment with antiepileptic drugs (AEDs). For clinicians to meet the challenges of patient management, data on AED performance based on clearly defined and consistently applied outcome measures are needed. Ideally, the design of AED clinical trials should be relevant to real-world settings, providing reliable, valid, and comprehensive information on efficacy, tolerability, and quality of life (QOL). Several types of outcome parameters have been employed: percent seizure reduction, responder rate based on > or =50% seizure reduction, seizure-free rate, time to first seizure, time to Nth seizure, adverse events, QOL, retention, and compliance. Each provides important information about a drug's performance. Here we define and review endpoints for measuring AED treatment success and explore the concepts of efficacy, tolerability, QOL, retention, and compliance as well as their usefulness as clinical trial endpoints.

Epilepsy outcomes in elderly treated with topiramate

OBJECTIVES

To explore effectiveness, tolerability and quality of life in elderly patients with epilepsy treated with topiramate.

METHODS

One year, open-label, flexible-dosing clinical trial.

RESULTS

One hundred and seven patients (mean age 69 years, 53% men) were studied during 273 +/- 141 days. The average final dose in monotherapy was 98 mg/day vs 153 mg/day in adjunctive treatment. Mean monthly cumulative seizure frequency decreased from 3.7 +/- 15 to 1.6 +/- 7.7 (n = 101, P < 0.0001), 78% of patients with seizures at baseline (n = 102) achieved at least 50% reduction in seizure frequency, 44% were seizure-free throughout the trial. Total scores on the quality of life in epilepsy inventory (QOLIE-31) improved from 57 +/- 17 to 68 +/- 18 (n = 64, P < 0.0001). The most frequently reported adverse events included convulsions, dizziness and tiredness.

CONCLUSIONS

Elderly patients treated with topiramate showed marked reductions in seizures, good tolerability and significant improvements in several aspects of quality of life.

Oxcarbazepine improves mood in patients with epilepsy

This study prospectively examined whether continued add-on treatment with oxcarbazepine (OXC) is associated with quantitative improvement in mood and anxiety symptoms in adult patients with partial epilepsy. Depressive symptoms and anxiety were assessed by clinical interview using the Hamilton Depression Rating Scale (HDRS), the Cornell Dysthymia Rating Scale (CDRS), the Beck Depression Inventory (BDI), and the Hamilton Anxiety Rating Scale (HARS). Forty controls (patients with epilepsy treated with antiepileptic drugs other than OXC) and 40 OXC-treated patients were enrolled and completed the study. In our study, a significant improvement in affect, as measured by the CDRS, was demonstrated during the course of OXC treatment for 3 months. HDRS and BDI scores also declined in the OXC-treated group, but these decreases did not reach statistical significance. In addition, 28 of 40 OXC-treated subjects who were dysthymic by CDRS criteria on study entry (score > or =20) demonstrated affective improvement consistent with a treatment-related antidepressant effect (score <20). Although our results do not provide conclusive evidence supporting the specific use of OXC as an antidepressant, the significant decline in dysthymic symptoms in OXC-treated subjects compared with controls lends support to the hypothesis that OXC improves mood.

Efficacy, safety, and tolerability of oxcarbazepine monotherapy

OBJECTIVE

This prospective, open-label, multicenter study evaluated the efficacy and tolerability of oxcarbazepine as monotherapy in patients with partial seizures who switched from their current antiepileptic drug (AED) monotherapy because of lack of efficacy or poor tolerability.

METHOD

Patients (>or=12 years old) experiencing 2-40 seizures per month while receiving an AED were included. During a 16-week treatment phase, oxcarbazepine was initiated (8-10mg/kg for children; 600 mg/day for adults) and titrated up over 4 weeks while the existing AED was tapered off. Improvement in seizure frequency (defined as >or=50% reduction compared with baseline) was evaluated for all patients, as well as the subgroups of patients switched due to poor tolerability or lack of efficacy.

RESULTS

Overall, 52% of patients experienced a 50% reduction in seizure frequency, 35% had a >or=75% reduction, and 18% were seizure-free. The most frequent (>10%) adverse events were dizziness, nausea, headache, somnolence, and fatigue. Overall, 17% of patients prematurely withdrew because of an adverse event; 62% of these withdrawals occurred during the conversion period.

CONCLUSION

Oxcarbazepine as monotherapy may be a favorable treatment option for patients with partial seizures or poor tolerability of their existing monotherapy regimen.