Multicenter double-blind, randomized, placebo-controlled trial of levetiracetam as add-on therapy in Chinese patients with refractory partial-onset seizures

Purpose:   To evaluate efficacy and tolerability of levetiracetam (LEV; Keppra^®) as add-on therapy in Chinese patients with refractory partial-onset seizures.
Methods:   In this multicenter, double-blind, randomized, placebo-controlled trial, 206 patients aged 16–70 years with uncontrolled partial-onset seizures were randomized to receive LEV (n =103) or placebo (n =103); 202 patients (LEV, n =102; placebo, n = 100) comprised the intent-to-treat population. An 8-week historical baseline period confirmed eligibility according to seizure count. The 16-week treatment period consisted of a 4-week up-titration period (LEV, 1,000–3,000 mg/day in two equal divided doses) followed by a 12-week maintenance period. Efficacy assessments were based on weekly frequency of partial-onset seizures during the 16-week treatment period.
Results:   LEV significantly decreased weekly partial-onset seizure frequency over placebo by 26.8% (p  < 0.001). Median percentage reductions in weekly partial-onset seizure frequency from historical baseline were 55.9% for LEV and 13.7% for placebo (p  < 0.001). The ≥50% responder rates were 55.9% for LEV, compared with 26.0% for placebo (p  < 0.001). Freedom from partial-onset seizures during treatment period was achieved by 11 LEV patients (10.8%) and 2 placebo patients (2.0%) (p = 0.012). Adverse events were reported by 65 LEV-treated patients (63.1%) and 62 placebo-treated patients (60.2%); most were of mild-to-moderate intensity. The most common adverse events were somnolence (LEV, 17.5%; placebo, 17.5%), decreased platelet count (LEV, 9.7%; placebo, 9.7%), and dizziness (LEV, 7.8%; placebo, 13.6%).
Discussion:   Add-on LEV was effective and well-tolerated in Chinese patients with refractory partial-onset seizures.     

Adjunctive levetiracetam in infants and young children with refractory partial-onset seizures

Purpose:   To evaluate the efficacy and tolerability of adjunctive levetiracetam in very young children (aged 1 month to <4 years) with partial-onset seizures inadequately controlled with one or two antiepileptic drugs.
Methods:   This multicenter, double-blind, randomized, placebo-controlled study consisted of a 48-h inpatient baseline video-EEG (electroencephalography) and a 5-day inpatient treatment period (1-day up-titration; 48-h evaluation video-EEG in the last 2 days). Children who experienced at least two partial-onset seizures during the 48-h baseline video-EEG were randomized to either levetiracetam [40 mg/kg/day (age 1 to <6 months); 50 mg/kg/day (age ≥6 months to <4 years] or placebo.
Results:   Of 175 patients screened, 116 patients were randomized [60 levetiracetam; 56 placebo; intent-to-treat (ITT) population], and 111 completed the study. The responder rate in average daily partial-onset seizures frequency (48-h video-EEG monitoring; primary efficacy variable) was 43.1% for levetiracetam [modified ITT (mITT) = 58] versus 19.6% for placebo (mITT = 51; p=0.013), with odds ratio for response 3.11 [95% confidence interval (CI), 1.22–8.26]. The median percent reduction from baseline in average daily partial-onset seizure frequency was 43.6% for levetiracetam and 7.1% for placebo with a median difference between treatment groups of 39.2% (95% CI, 17.5–62.2; p   <   0.001). In general, levetiracetam was well tolerated. Treatment-emergent adverse events were reported by 55.0% levetiracetam- and 44.6% placebo-treated patients (ITT population). The most frequently reported adverse events were somnolence (13.3% levetiracetam, 1.8% placebo) and irritability (11.7% levetiracetam, 0% placebo).
Discussion:   Adjunctive levetiracetam is an efficacious and well-tolerated treatment for partial-onset seizures in infants and young children.     

A randomized, double-blind, placebo-controlled, parallel-group study of rufinamide as adjunctive therapy for refractory partial-onset seizures

Purpose: Efficacy and safety of adjunctive rufinamide (3,200 mg/day) was assessed in adolescents and adults with inadequately controlled partial‐onset seizures receiving maintenance therapy with up to three antiepileptic drugs (AEDs). Methods: This randomized, double‐blind, placebo‐controlled, parallel‐group, multicenter study comprised a 56‐day baseline phase (BP), 12‐day titration phase, and 84‐day maintenance phase (MP). The primary efficacy variable was percentage change in total partial seizure frequency per 28 days (MP vs. BP). Secondary efficacy outcome measures included ≥50% responder rate and reduction in mean total partial seizure frequency during the MP. Safety and tolerability evaluation included adverse events (AEs), physical and neurologic examinations, and laboratory values. Pharmacokinetic and pharmacodynamic assessments were conducted. Results: Three hundred fifty‐seven patients were randomized: 176 to rufinamide and 181 to placebo. Patients had a median of 13.3 seizures per 28 days during BP; 86% were receiving ≥2 AEDs. For the intent‐to‐treat population, the median percentage reduction in total partial seizure frequency per 28 days was 23.25 for rufinamide versus 9.80 for placebo (p = 0.007). Rufinamide‐treated patients were more than twice as likely to have had a ≥50% reduction in partial seizure frequency (32.5% vs. 14.3%; p < 0.001) and had a greater reduction in median total partial seizure rate per 28 days during the MP (13.2 vs. 5.2; p < 0.001). Treatment‐emergent AEs occurring at ≥5% higher incidence in the rufinamide group compared with placebo were dizziness, fatigue, nausea, somnolence, and diplopia. Conclusions: Adjunctive treatment with rufinamide reduced total partial seizures in refractory patients. AEs reported were consistent with the known tolerability profile of rufinamide.     

Rufinamide: a double-blind, placebo-controlled proof of principle trial in patients with epilepsy

OBJECTIVE: This was the first proof of principle clinical trial assessing the efficacy and safety of rufinamide as adjunctive therapy in epileptic patients. The pharmacokinetic (PK) profile of rufinamide was also determined. METHODS: Fifty patients with diagnoses of partial or primary generalized tonic-clonic seizures were enrolled in this 28-day double-blind, placebo-controlled, weekly rising dose (400-1600 mg/day) trial. PK profiles were obtained after administration of single-dose rufinamide prior to and after the Double-blind phase. RESULTS: In the evaluable patient population, seizure frequency decreased by 41% in the rufinamide group and increased by 52% in the placebo group (P=0.040). Thirty-nine percent (39%) of rufinamide-treated and 16% of placebo-treated patients experienced reduction in seizure frequency of at least 50% relative to baseline (P=0.096). SAFETY: Treatment-emergent adverse events (AEs) consisted mainly of neurologic signs and symptoms commonly associated with antiepileptic drugs (AEDs). PHARMACOKINETICS: At steady state, rufinamide reached a peak plasma concentration with a mean time (Tmax) of 3.4 h and a mean half-life (t1/2) of 7.3 h. No autoinduction of rufinamide metabolism occurred. Rufinamide did not influence the plasma concentration of carbamazepine, phenytoin or valproate when added to these single AED regimens. CONCLUSION: Rufinamide has been shown, in this proof of principle trial, to be safe and effective in reducing seizure frequency in epileptic patients with no relevant influence on the metabolism of other AEDs.     

Dose–Response Study of Vigabatrin as Add-On Therapy in Patients with Uncontrolled Complex Partial Seizures

Summary: Purpose: This placebo-controlled, randomized, double-blind, multicenter study examined the efficacy and safety of three daily doses of vigabatrin (VGB; 1, 3, or 6 g) as add-on therapy in 174 patients with previously uncontrolled complex partial seizures with or without secondary generalization.
Methods: A 12-week pretreatment assessment period was followed by drug therapy with a 6-week titration period and a 12-week maintenance phase.
Results: VGB doses of 3 and 6 g/day reduced median monthly frequency of seizures by 4.3 and 4.5 seizures, respectively, compared with 0.2 seizures for placebo (p = 0.0001). The percentages of patients classified as therapeutic successes (≤50% reduction in seizure frequency) were 7% for placebo and 24, 51, and 54% for patients taking daily VGB doses of 1, 3, and 6 g, respectively; the comparison with placebo was significant for all treatment groups. The linear trend for dose response was highly significant (p ≥ 0.0001) for both median monthly seizure frequency and therapeutic success. Vigabatrin was well tolerated, causing no clinically significant changes in laboratory parameters, brain magnetic resonance imaging, evoked potentials, cognitive function, or psychosocial tests. Fatigue, drowsiness, and dizziness were the most common treatment-related adverse events in all treatment groups. Dropouts due to adverse events were higher in the 6-g/day group.
Conclusions: VGB was significantly more effective than placebo as add-on therapy in reducing seizure frequency. VGB at 3 and 6 g/day produced the best efficacy: however, adverse events may limit the use of the 6-g/day dose in some patients.     

Rapid onset of seizure suppression with pregabalin adjunctive treatment in patients with partial seizures

Purpose:  To determine the time at which pregabalin demonstrates seizure-suppressing activity when given as adjunctive treatment to patients with refractory partial seizures.
Methods:  Data from four similar 12-week, randomized, double-blind, placebo-controlled, parallel-group trials in patients with refractory partial seizures were pooled to provide an adequate sample to compare the proportion of patients free of seizures on each study day between pregabalin (combined 150–600 mg/day groups) and placebo (combined groups). A generalized estimating equation (GEE) statistical model was used to perform pairwise comparisons on each study day. In several pregabalin dosage groups the dosage was escalated during days 1–7, whereas in others pregabalin was initiated at a fixed dosage without escalation.
Results:  The proportion of patients free of seizures on any treatment day was greater in the combined pregabalin groups compared with baseline. Differences were not observed between the placebo group and baseline. A significantly greater proportion of patients were free of seizures in the combined pregabalin 150–600 mg/day and the pregabalin 600 mg/day fixed-dosage groups compared with the placebo groups from treatment day 2 onward (p < 0.05). From day 8 (coinciding with completion of the 1-week dosage-escalation period in two studies) onward, the proportion of patients free of seizures per day in the pregabalin groups remained relatively constant.
Discussion:  This exploratory analysis of a refractory population using a rigorous endpoint demonstrates that pregabalin rapidly reduced the frequency of partial seizures. At the dosing schemes most commonly used in placebo-controlled trials, significant seizure-suppressing activity was observed after only 2 days of treatment.     

Pregabalin As Adjunctive Therapy for Partial Seizures

Summary:  The efficacy and safety of pregabalin as adjunctive therapy for patients with partial epilepsy with or without secondary generalization has been studied in three randomized, double-blind, placebo-controlled trials involving 1,052 patients. Patients (≥12 years of age) participating in the trials were highly refractory to treatment, experiencing at least six seizures and no 4-week seizure-free period during the 8-week baseline phase, even though 73% received at least two antiepileptic drugs and 23% received three. Each fixed-dose study was 12 weeks in duration. In Study 1, patients received pregabalin 50, 150, 300, or 600 mg/day given two times daily with no titration period. Studies 2 and 3 had a 1-week titration to dose levels of 150 and 600 mg/day given three times daily (Study 2), 600 mg/day given two times daily, and 600 mg/day given three times daily (Study 3). Pregabalin, at 150, 300, and 600 mg/day, was significantly superior to placebo in reducing seizure frequency with a clear dose–response relationship. Responder rates, defined as the percentage of patients with ≥50% reduction in seizure frequency from baseline, approached 50% at 600 mg/day. In the effective dose range (150–600 mg/day), seizure freedom in the last 28 days of treatment was 3–17%. There was no difference between two times daily and three times daily dosing regimens. Efficacy was apparent as early as week one. The most commonly reported adverse events were CNS related, and either mild or moderate in intensity and generally self limiting. Few patients (≤5% in any treatment group) discontinued due to lack of efficacy. These results indicate that pregabalin is highly effective as adjunctive therapy in the treatment of patients with partial seizures with or without secondary generalization.     

Efficacy and tolerability of levetiracetam 3000 mg/d in patients with refractory partial seizures: a multicenter, double-blind, responder-selected study evaluating monotherapy. European Levetiracetam Study Group

PURPOSE: To evaluate the efficacy and tolerability of levetiracetam (LEV) monotherapy in selected patients with refractory partial seizures. METHODS: In this multicenter, double-blind, placebo-controlled, parallel-group, responder-selected study, patients were randomized (2:1 ratio) to receive oral LEV 1500 mg twice daily or placebo during a 12-week add-on phase. Treatment responders (patients with a reduction in partial seizure frequency of 50% or more compared with baseline) entered a monotherapy phase that included a maximum 12-week down-titration period and 12 weeks of monotherapy at 1500 mg twice daily. In both phases, responder rate, seizure frequency, and adverse events were analyzed. RESULTS: A total of 286 patients (placebo, n = 105; LEV, n = 181) entered the add-on phase, and 86 patients (placebo, n = 17; LEV, n = 69) were eligible for the monotherapy phase. Thirty-six of 181 patients (19.9%) who received LEV completed the entire study compared with only 10 of 105 patients (9.5%) in the placebo group (p = 0.029). The odds of completing the study on LEV were 2.36 times (95% confidence interval, 1.08, 5.57) higher than on placebo. The responder rate during the add-on phase was significantly higher in the LEV group compared with the placebo group (42.1% vs. 16.7%, respectively; p < 0.001). In the LEV monotherapy group, the median percent reduction in partial seizure frequency compared with baseline was 73.8% (p = 0.037), with a responder rate of 59.2%. Nine patients (18.4%) remained seizure-free on LEV monotherapy. CONCLUSIONS: Conversion to LEV monotherapy (1500 mg twice daily) is effective and well tolerated in patients with refractory partial seizures who responded to 3000 mg/d LEV as add-on therapy.     

Vagus nerve stimulation for refractory epilepsy in children: More to VNS than seizure frequency reduction

Purpose :  Vagus nerve stimulation (VNS) is used increasingly as adjunctive therapy for refractory epilepsy. Studies of VNS in children report mainly seizure frequency reduction as a measure of efficacy and clinical details are often scanty. We report our experience with VNS in children with refractory epilepsy and emphasize the positive effects of VNS in terms of seizure severity.
Methods :  We reviewed 26 consecutive children who had VNS with a minimum follow-up period of 18 months. We examined their clinical characteristics, seizure types, seizure frequency, epilepsy syndrome diagnosis, and response to VNS in terms of seizure frequency and seizure severity.
Results :  Fifty-four percent of patients responded to VNS with ≥50% seizure frequency reduction. Patients with Lennox-Gastaut syndrome (LGS) and tonic seizures had a higher responder rate; 78% (seven of nine patients) (p < 0.01). Status epilepticus (SE) episodes were reduced or ceased in the four patients with recurrent SE. Seizure severity, duration, and recovery time decreased in all responders. Increased alertness was reported in all responders and three nonresponders.
Conclusion :  Decreased seizure severity, recovery time, abolition of daytime drop attacks, and reduced hospitalization due to SE improved patients' lives over and above the benefit from seizure frequency reduction.     

Efficacy of felbamate monotherapy in patients undergoing presurgical evaluation of partial seizures

The efficacy and safety of felbamate monotherapy were evaluated in 52 patients with refractory partial seizures with or without secondary generalization in a double-blind, randomized, placebo-controlled trial. Each patient completed a routine evaluation for epilepsy surgery and was randomized to receive either felbamate, titrated to a maximum daily dose of 3600 mg over 2 days, or placebo during the 10-day, inpatient, treatment phase. An intent-to-treat analysis was performed on the data of all 52 patients who received study medication, while a separate efficacy analysis also was performed on the data of 43 evaluable patients, which excluded protocol violators. The endpoint of the trial was completing 10 days of treatment or the occurrence of a fourth seizure. The primary efficacy variable was the average daily seizure frequency during the treatment phase for each patient. For the intent-to-treat analysis based on all 52 patients who received study medications, the mean rank of the daily seizure frequency for patients treated with felbamate was 21.6 compared to 29.6 for patients treated with placebo (P = 0.065). In the analysis based on the 43 evaluable patients, the mean rank of the daily seizure frequency for felbamate-treated patients was 17.0 compared to 25.4 for placebo-treated patients. This difference was statistically significant (P = 0.032) in favor of felbamate. Seizure frequency was decreased by 89.5% compared to baseline in nine patients who completed 10 days of felbamate therapy. This study permitted the rapid determination of the anticonvulsant activity of felbamate and demonstrated that felbamate is effective as monotherapy for the treatment of partial seizures.     

Felbamate: A Clinical Trial for Complex Partial Seizures

We performed a randomized, double-blind, three-period cross-over study of felbamate (FBM, 2-phenyl-1,3-propanediol dicarbamate: Carter-Wallace 554) in patients with complex partial seizures. Patients continued carbamazepine (CBZ) throughout the study and were observed in the hospital for the entire trial period. The entry criteria required at least six seizures in a 3-week baseline period (and no more than 1 week with a single seizure) with CBZ alone. Thirty subjects were randomized. Two left the study after randomization, 1 owing to seizure exacerbation, and 1 owing to hyponatremia, which may have been related to CBZ therapy. The daily dosage of 50 mg/kg (maximum 3,000 mg) FBM per day was well tolerated by all 28 patients who completed the study. Only mild adverse experience were observed during the trial. FBM reduced CBZ level (p less than 0.0001; 95% confidence interval -28%, -20%). There was no significant difference in seizure frequency between placebo and FBM periods (one-sided p = 0.172), but when a correction was made for the lower CBZ level noted during FBM periods, the data suggested a strong antiseizure effect of FBM.     

Adjunctive lacosamide for partial-onset seizures: Efficacy and safety results from a randomized controlled trial

Purpose:   To evaluate the efficacy and safety of lacosamide (200 and 400 mg/day) when added to one to three concomitant antiepileptic drugs (AEDs) in patients with uncontrolled partial-onset seizures.
Methods:   This multicenter, double-blind, placebo-controlled trial randomized patients (age 16–70 years) with partial-onset seizures with or without secondary generalization to placebo, lacosamide 200, or lacosamide 400 mg/day. The trial consisted of an 8-week baseline, a 4-week titration, and a 12-week maintenance period.
Results:   Four hundred eighty-five patients were randomized and received trial medication. Among these, 87% were taking two or more concomitant AEDs. Median percent reduction in seizure frequency per 28 days from baseline to maintenance period (intent-to-treat, ITT) was 20.5% for placebo, 35.3% for lacosamide 200 mg/day (p   =   0.02), and 36.4% for 400 mg/day (p   =   0.03). In the per protocol population, the reductions were 35.3% for lacosamide 200 mg/day (p   =   0.04) and 44.9% for 400 mg/day (p   =   0.01) compared to placebo (25.4%). The 50% responder rate for lacosamide 400 mg/day (40.5%) was significant (p   =   0.01) over placebo (25.8%), but was not for 200 mg/day (35.0%). In the per protocol population, the 50% responder rate for lacosamide 400 mg/day (46.3%) was significant (p   <   0.01) compared with the placebo responder rate (27.5%). Dose-related adverse events (AEs) included dizziness, nausea, and vomiting. Clinically relevant changes in the mean plasma concentrations of commonly used AEDs were not observed.
Discussion:   Results of this trial demonstrated the efficacy and tolerability of adjunctive lacosamide 200 and 400 mg/day and support that lacosamide may be an advantageous option for the treatment of partial-onset seizures in patients with epilepsy.     

Efficacy and safety of eslicarbazepine acetate as adjunctive treatment in adults with refractory partial-onset seizures: A randomized, double-blind, placebo-controlled, parallel-group phase III study

Purpose: To study the efficacy and safety of eslicarbazepine acetate (ESL) as adjunctive therapy for refractory partial seizures in adults with ≥4 partial‐onset seizures (simple or complex, with or without secondary generalization) per 4 weeks despite treatment with 1–2 antiepileptic drugs (AEDs). Methods: This multicenter, parallel‐group study had an 8‐week, single‐blind, placebo baseline phase, after which patients were randomized to placebo (n = 102) or once‐daily ESL 400 mg (n = 100), 800 mg (n = 98), or 1,200 mg (n = 102) in the double‐blind treatment phase. ESL starting dose was 400 mg; thereafter, ESL was titrated at weekly 400‐mg steps to the full maintenance dose (12 weeks). Results: Seizure frequency adjusted per 4 weeks over the maintenance period (primary endpoint) was significantly lower than placebo in the ESL 1,200‐mg (p = 0.0003) and 800‐mg (p = 0.0028) groups [analysis of covariance (ANCOVA) of log‐transformed seizure frequency]. Responder rate was 20% (placebo), 23% (400 mg), 34% (800 mg), and 43% (1,200 mg). Median relative reduction in seizure frequency was 16% (placebo), 26% (400 mg), 36% (800 mg), and 45% (1,200 mg). The most frequent concomitant AEDs were carbamazepine (56–62% of patients), lamotrigine (25–27%), and valproic acid (22–28%). Similar efficacy results were obtained in patients administered ESL with or without carbamazepine as concomitant AED. Discontinuation rates caused by adverse events (AEs) were 3.9% (placebo), 4% (400 mg), 8.2% (800 mg), and 19.6% (1,200 mg). AEs in >10% of any group were dizziness, headache, and diplopia. Most AEs were mild or moderate. Discussion: ESL, 800 and 1,200 mg once‐daily, was well tolerated and more effective than placebo in patients who were refractory to treatment with one or two concomitant AEDs.     

Multicenter double-blind, randomized, placebo-controlled trial of levetiracetam as add-on therapy in patients with refractory partial seizures. European Levetiracetam Study Group

PURPOSE: To evaluate the efficacy and tolerability of levetiracetam (LEV, Keppra) as add-on therapy in patients with refractory partial seizures. METHODS: In this European multicenter, double-blind, randomized, placebo-controlled trial, LEV (500 or 1,000 mg twice daily) was compared with placebo as add-on therapy in 324 patients with uncontrolled simple or complex partial seizures, or both, with or without secondary generalization. After enrollment, three parallel groups were assessed during a baseline period of 8 or 12 weeks, followed by a 4-week titration interval and a 12-week evaluation period. RESULTS: LEV significantly decreased partial seizure frequency compared with placebo. A reduction in seizure frequency of > or =50% occurred in 22.8% of patients in the 1,000-mg group and 31.6% of patients in the 2,000-mg group, compared with 10.4% of patients in the placebo group. Administration of LEV did not affect plasma concentrations of concomitant antiepileptic drugs or alter vital signs or laboratory parameters. No significant difference in the incidence of adverse events was observed between treatment groups (70.8% for the 1,000-mg group and 75.5% for the 2,000-mg group), or between the LEV and placebo groups (73.2% for placebo group). The most commonly reported adverse effects in the LEV group were asthenia, headache, and somnolence. CONCLUSIONS: The antiepileptic efficacy and tolerability of LEV (1,000 mg/d and 2,000 mg/d, administered in two divided doses) as add-on therapy was established in patients with refractory partial seizures in this clinical study.     

Lacosamide as adjunctive therapy for partial‐onset seizures: A randomized controlled trial

Purpose: To evaluate the efficacy and safety of lacosamide (400 and 600 mg/day) as adjunctive treatment in patients with uncontrolled partial‐onset seizures taking one to three concomitant antiepileptic drugs (AEDs). Methods: This multicenter, double‐blind, placebo‐controlled trial randomized patients 1:2:1 to placebo, lacosamide 400 mg, or lacosamide 600 mg/day. After an 8‐week baseline period, patients began treatment with placebo or lacosamide 100 mg/day, were force‐titrated weekly (100 mg/day increments) to the target dose, and entered a 12‐week maintenance period. Results: A total of 405 patients were randomized and received trial medication. Most (82.1%) were taking two to three concomitant AEDs. Median percent reductions in seizure frequency per 28 days from baseline to maintenance (intention‐to‐treat, ITT) were 37.3% for lacosamide 400 mg/day (p = 0.008) and 37.8% for lacosamide 600 mg/day (p = 0.006) compared to 20.8% for placebo, with responder rates of 38.3% and 41.2%, respectively, compared to placebo (18.3%, p < 0.001; ITT). Patients randomized to lacosamide showed large reductions in secondarily generalized tonic–clonic seizures, with median percent reductions in seizure frequency of 59.4% for lacosamide 400 mg/day and 93.0% for lacosamide 600 mg/day compared to 14.3% for placebo, and responder rates of 56.0% and 70.2% compared to placebo (33.3%). Dose‐related adverse events included dizziness, nausea, and vomiting. Discussion: Adjunctive treatment with lacosamide 400 and 600 mg/day reduced seizure frequency for patients with uncontrolled partial‐onset seizures. Lacosamide 400 mg/day provided a good balance of efficacy and tolerability; lacosamide 600 mg/day may provide additional benefit for some patients as suggested by secondary efficacy analyses, including response in patients with secondarily generalized tonic–clonic seizures.     

Gabapentin as Add-On Therapy in Children with Refractory Partial Seizures: A 12-Week, Multicentre, Double-Blind, Placebo-Controlled Study

PURPOSE: To evaluate the efficacy and safety of gabapentin (Neurontin; GBP) as add-on therapy for refractory partial seizures in paediatric patients aged 3-12 years. METHODS: After a 6-week baseline period, 247 patients (54 centres) entered a 12-week double-blind phase and were randomized to receive either GBP (t.i.d., titrated to 23-35 mg/kg/ day) or placebo. Seizure activity and type were recorded daily. Efficacy variables included Response Ratio (RRatio), responder rate, and percentage change in frequency (PCH) for all partial seizures; PCH and RRatio for individual types of partial seizures; and investigator and parent/guardian global assessments of seizure frequency and patient well-being. RESULTS: RRatio for all partial seizures was significantly lower (better) for GBP-treated patients (p = 0.0407). Responder rate favored GBP, but the difference between treatment groups was not statistically significant. Median PCH for all partial seizures for the GBP treatment group (-17.0%) was better than that for the placebo group (-6.5%). Median PCH for specific seizure types showed GBP to be most effective in controlling complex partial seizures (-35%) and secondarily generalized seizures (-28%) when compared with placebo (-12%, +13%, respectively). A greater percentage of GBP-treated patients exhibited improvement according to investigator and parent/guardian global assessments, with a statistically significant difference observed in the parent/guardian global assessment of seizure-frequency reduction (p = 0.046). Three GBP patients and one placebo patient were seizure free during the double-blind treatment period. GBP was well tolerated. CONCLUSIONS: GBP was effective and well tolerated as an add-on therapy for partial seizures in paediatric patients with previously drug-resistant seizures.     

Topiramate Monotherapy for Partial Onset Seizures

Summary: Purpose: Evaluation of topiramate (TPM) as monotherapy in patients with uncontrolled partial onset seizures.
Methods: A total of 48 patients were evaluated in a doubleblind, parallel-group trial. During a 56-day baseline period, patients had at least eight partial onset seizures while being treated with one or two standard antiepileptic drugs (AEDs). After 1–2 weeks of open-label treatment with TPM 100 mg/day, patients were randomly assigned, in equal proportions, to receive double-blind therapy with TPM 100 or 1,000 mg/day in a 5-week conversion and an 11-week monotherapy period. The study endpoint was completion of 112 study days (success) or fulfillment of one or more exit criteria: doubling of average 28- day or highest 2-day baseline seizure rate, a generalized tonic-clonic seizure (GTCS) if none had occurred at baseline, or significant prolongation of generalized seizure duration.
Results: Time until exit was longer (p = 0.002) and success frequency was higher (p = 0.005) with TPM 1,000 as compared with 100 mg/day. Seizure-rate reductions of 50, 75, or 100% were achieved by 46, 25, and 13% of the 1,000-mg/day group, respectively, as compared with 13, 8, and 0% of the 100-mg/day group, respectively. Most adverse events (AE) were mild or moderate in severity.
Conclusions: Monotherapy with TPM 1,000 mg/day for partial onset seizures with or without secondarily generalized seizures was effective, with a favorable safety profile.     

Once-daily extended-release levetiracetam as adjunctive treatment of partial-onset seizures in patients with epilepsy: A double-blind, randomized, placebo-controlled trial

Purpose:   Double-blind randomized trial to assess efficacy and tolerability of once-daily extended-release levetiracetam (LEV XR) tablets (2 × 500 mg) as add-on therapy in patients (12–70 years old) with partial-onset seizures (POS) refractory to one to three antiepileptic drugs.
Methods:   After an 8-week prospective baseline-period, eligible patients were randomized (1:1) to once-daily LEV XR 1,000 mg/day or placebo for 12 weeks. Evaluations included changes from baseline in POS-frequency/week, responders (≥50% reduction in POS-frequency/week), seizure-freedom, adverse events, laboratory tests, physical and neurologic examinations, vital signs, body-weight, and 12-lead electrocardiogram.
Results:   Of 188 patients screened, 158 were randomized (intention-to-treat population): LEV XR (n = 79) or placebo (n = 79). Seventy-one (89.9%) LEV XR and 72 (91.1%) placebo patients completed the trial. Median POS-frequency/week reduction was 46.1% on LEV XR and 33.4% on placebo. Estimated reduction with LEV XR over placebo was 14.4% (p   =   0.038). Thirty-four (43%) LEV XR and 23 (29.1%) placebo patients experienced ≥50% reduction in POS-frequency/week. Eight (10.1%) patients receiving LEV XR and one (1.3%) receiving placebo were free of POS during the 12-week treatment period. Forty-one (53.2%) LEV XR and 43 (54.4%) placebo patients reported ≥1 adverse event. Adverse events reported with an incidence >5% and seen more often with LEV XR than with placebo were somnolence, influenza, irritability, nasopharyngitis, dizziness, and nausea .
Discussion:   Once-daily LEV XR 1,000 mg was effective and well-tolerated as adjunct therapy in patients with POS. Ten percent of patients randomized to LEV XR experienced freedom from POS. These results support the clinical value of this new LEV XR formulation.     

Treatment of partial seizures with gabapentin: double-blind, placebo-controlled, parallel-group study

This double-blind study was conducted to evaluate the efficacy and safety of gabapentin 1200 mg/day and 1800 mg/day (t.i.d.) compared to placebo as an adjunctive therapy in patients with refractory epilepsy. Patients were included when they had partial seizures at least eight times during a 12-week baseline period despite treatment with one to two antiepileptic drugs. After baseline, eligible patients were randomized to gabapentin 1200 mg/day, 1800 mg/day, or placebo for 12-week treatment. The primary end-point, response ratio, was derived from seizure frequencies during treatment and baseline period based upon the seizure daily record by a patient. Of the 209 randomized patients, 86 received gabapentin 1200 mg/day, 41 received gabapentin 1800 mg/day, and 82 received placebo. A statistically significant difference was found between each of the two gabapentin groups and placebo for the primary efficacy end-point, response ratio (P < 0.005) with definite dose-response (P < 0.001). More gabapentin patients reported moderate to marked improvement in seizure frequency and intensity/duration of each seizure than placebo patients. Treatment-related adverse events were reported by approximately 65% of patients receiving gabapentin compared to approximately 46% of patients receiving placebo; somnolence and dizziness were the most common events. Gabapentin 1200 mg/day and 1800 mg/day significantly reduced the frequency of refractory seizures compared to placebo. Favorable tolerability of gabapentin was confirmed also in a Japanese population, consistent with previous global studies.