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.     

Pregabalin add-on treatment in patients with partial seizures: a novel evaluation of flexible-dose and fixed-dose treatment in a double-blind, placebo-controlled study

PURPOSE: To evaluate pregabalin as add-on therapy for patients with partial seizures administered as fixed dose or as flexible dose adjusted to optimal seizure reduction and tolerability. METHODS: Patients receiving antiepileptic drugs (98.8% between 1 and 3 AEDs; 1.2% on more than 3 AEDs) and experiencing > or =4 partial seizures during the 6-week baseline period and no 4-week seizure-free interval were randomized (1:2:2) to placebo (n = 73), pregabalin fixed dose (600 mg/day BID; n = 137), or pregabalin flexible dose (n = 131; 150 and 300 mg/day for 2 weeks each; 450 and 600 mg/day for 4 weeks each, BID) for 12 weeks. Dosage could be adjusted based on tolerability and maintained when a 4-week seizure-free period was achieved. Primary efficacy parameter was reduction in seizure frequency from baseline. RESULTS: Both pregabalin regimens significantly reduced seizure frequency compared with placebo, by 35.4%, for flexible dose (p = 0.0091) and 49.3% for fixed dose (p = 0.0001) versus 10.6% for placebo, and the fixed-dose group was superior to the flexible-dose group (p = 0.0337). Most adverse events were mild or moderate. Discontinuation rates due to adverse events were 6.8% (placebo), 12.2% (pregabalin flexible dose), and 32.8% (pregabalin fixed dose). Patients receiving pregabalin fixed dose discontinued due to adverse event earlier than other groups. CONCLUSIONS: Pregabalin administered twice daily, either as fixed (600 mg/day), or as flexible (150-600 mg/day) dose, was highly effective and generally well-tolerated as add-on therapy for partial seizures with or without secondary generalization. Lower incidence of adverse events and discontinuations were achieved in patients receiving pregabalin when dosing was individualized to optimize efficacy and tolerability.     

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.     

Double-Blind, Placebo-Controlled, Lamotrigine in Treatment-Resistant Generalised Epilepsy

Summary: Purpose : Lamotrigine (LTG) is recognised as effective add-on therapy for focal epilepsies, but this is the first double-blind, placebo-controlled, crossover study in treatmentresistant generalised epilepsy.
Methods: The study consisted of 2 × 8-week treatment periods followed by a 4-week washout period. Patients received doses of either 75 or 150 mg daily, depending on their concomitant antiepileptic drugs (AEDs). Long-term continuation was offered at the end of the study with open-label LTG.
Results: Five centres in Australia recruited 26 patients who were having absence, myoclonic, or generalized tonic-clonic seizures or a combination of these. Twenty-two patients completed the study. There was a significant reduction in frequency of both tonic-clonic and absence seizure types with LTG. A 250% decrease in seizures was observed for tonic-clonic seizures in 50% of cases and for absence seizures in 33% of evaluable cases. Rash was the only adverse effect causing discontinuation. Twenty-three of 26 opted for open-label LTG, with 20 still receiving LTG for a mean of 26 months. In these 20, 80% had 250% seizure reduction and five (25%) were seizure free.
Conclusions: This study shows that LTG is effective add-on therapy in patients with refractory generalised epilepsies. Statistically significant reduction in seizures in both absence and tonic-clonic seizure types was seen even with low doses of LTG.     

Dose-dependent safety and efficacy of zonisamide: a randomized, double-blind, placebo-controlled study in patients with refractory partial seizures

PURPOSE: To evaluate the safety and efficacy of zonisamide (ZNS) as adjunctive treatment in patients with refractory localization-related epilepsy. METHODS: This was a double-blind, placebo-controlled study of adjunctive ZNS in 351 patients with refractory partial seizures receiving a stable regimen of one to three antiepileptic drugs (AEDs). Patients were randomized to placebo or ZNS, 100 mg, 300 mg, or 500 mg/day (2:1:1:2) after a 12-week baseline. Dose titration was undertaken over a 6-week titration phase, which was followed by an 18-week fixed-dose assessment phase. Primary efficacy parameters were the differences between ZNS, 500 mg/day, and placebo in the change from baseline in frequency of complex partial (CP) seizures during the fixed-dose assessment phase and in the proportion of CP responders (> or =50% decrease from baseline in seizure frequency). Safety and tolerability also were assessed. RESULTS: Compared with placebo, the highest dose of ZNS (500 mg/day) resulted in a significantly greater decrease in CP seizure frequency from baseline (51.2% vs. 16.3%; p < 0.0001) and a significantly higher proportion of CP responders (52.3% vs. 21.3%; p < 0.001). Both ZNS, 500 mg/day, and 300 mg/day were statistically superior to placebo in reducing the frequency of "all seizures" and simple partial (SP) + CP seizures. For all seizures, a significant dose-response relation was observed (p < 0.0001).The most common adverse events were somnolence, headache, dizziness, and nausea during the titration phase and headache and pharyngitis during the fixed-dose assessment phase. CONCLUSIONS: ZNS provides dose-dependent, effective, and generally well-tolerated adjunctive therapy in patients with partial 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.     

Rufinamide for the adjunctive treatment of partial seizures in adults and adolescents: A randomized placebo-controlled trial

Purpose:   To evaluate efficacy and safety of adjunctive treatment with rufinamide 1600 mg twice daily in subjects aged ≥16 years with refractory partial seizures.
Methods:   This double-blind, placebo-controlled, randomized, parallel-group, multicenter trial included an 8-week baseline phase and a 13-week double-blind phase. Treatment was initiated with rufinamide 400 mg twice daily or placebo; rufinamide was titrated to 1600 mg twice daily. Percentage change in partial seizure frequency was the primary outcome measure. Secondary outcome measures included total partial seizure frequency and the percentage of subjects experiencing a ≥50% reduction in partial seizure frequency.
Results:   Three hundred thirteen subjects were randomized; 156 subjects received rufinamide and 157 received placebo. Rufinamide-treated subjects experienced a 20.4% median reduction in partial seizure frequency relative to baseline, while placebo-treated subjects had an increase of 1.6% (p = 0.02). Exclusion of subjects taking carbamazepine in a post hoc analysis resulted in a reduction of 29.2% versus 0.7% in the placebo group (p = 0.05), whereas the treatment difference in subjects taking carbamazepine was not significant. Of rufinamide-treated subjects, 28.2% experienced a ≥50% decrease in partial seizure frequency versus 18.6% of placebo-treated subjects (p = 0.04). The most common adverse events associated with rufinamide treatment were dizziness, nausea, diplopia, and ataxia; they occurred primarily during the titration phase.
Discussion:   Adjunctive therapy with rufinamide 3200 mg/day compared with matching placebo demonstrated efficacy and was generally well tolerated in adults with partial seizures. Further study of this agent in adults with partial seizures taking a range of baseline AEDs is warranted.     

Vigabatrin in complex partial seizures: a long-term study

The efficacy and safety of oral vigabatrin (VGB) as add-on therapy in the long-term treatment of poorly controlled epilepsy were evaluated in 19 patients with complex partial seizures, either with or without secondary generalization. The study was run with a single-blind, placebo-controlled, crossover design, and included 2 months of placebo and 13-15 months of treatment with VGB, at doses ranging from 1 to 4 g/day. Of the 14 patients who completed the trial, 2 were seizure free, in 5 seizure frequency dropped by more than 75% and in another 5 by more than 50% with respect to baseline. The decrease in seizure frequency in the group as a whole was significant at all observation points of the trial. Three patients were not entered into the long-term phase due to lack of improvement (an increase in seizure frequency was observed in one of them), and 2 were excluded later because improvement disappeared leading to unauthorized changes in comedication. Side effects were mild and never caused discontinuation of treatment. In conclusion, VGB showed a remarkable efficacy and safety in the long-term treatment of complex partial seizures.     

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.     

Tiagabine: Efficacy and Safety in Adjunctive Treatment of Partial Seizures

PURPOSE: To assess the efficacy and safety of tiagabine (TGB), a new antiepileptic drug (AED), as add-on therapy in patients with refractory partial seizures. METHODS: This response-dependent study used an open-label screening phase (in which patients were titrated to their optimal TGB dose, < or =64 mg/day) followed by a double-blind, placebo-controlled, crossover phase. Initial eligibility criteria included (a) seizures inadequately controlled by existing AEDs, and (b) six or more partial seizures during an 8-week baseline period. Patients showing benefit from TGB (> or =25% reduction in total seizure rate relative to baseline) were eligible for randomization into the double-blind phase, which comprised two 7-week assessment periods separated by a 3-week crossover period. RESULTS: Forty-four (50%) of the 88 enrolled patients entered the double-blind phase of the study during which there were significant reductions compared with placebo in all partial (p < 0.01), complex partial (p < 0.001), and secondarily generalized tonic-clonic seizure rates (p < 0.05). Thirty-three percent of patients experienced a reduction of > or =50% in the all partial seizure rate. Eight (22%) patients receiving TGB during the double-blind phase reported adverse events, of which dizziness and incoordination were the most frequent. Three patients withdrew from treatment during the double-blind phase because of adverse events; two during treatment with TGB and one during treatment with placebo. TGB did not affect plasma concentrations of other coadministered AEDs. CONCLUSIONS: TGB was significantly better than placebo in terms of seizure rate reduction and was generally well-tolerated in patients with difficult to control 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.     

Efficacy and safety of levetiracetam in children with partial seizures: an open-label trial

PURPOSE: To assess the efficacy and safety of levetiracetam (LEV) as adjunctive therapy in children with treatment-resistant partial-onset seizures. METHODS: Children (aged 6-12 years) with treatment-resistant partial-onset seizures receiving one standard antiepileptic drug (AED) were eligible. After a 4-week baseline period, children received LEV in a 6-week titration phase (target dose, 40 mg/kg/day) followed by an 8-week evaluation phase. Seizure frequency during the evaluation period with individualized LEV doses (20-40 mg/kg/day) were compared with the 4-week baseline seizure frequency. Plasma concentrations of LEV and other AEDs were determined to evaluate potential drug interactions. RESULTS: Twenty-four subjects enrolled and received LEV; 23 entered the evaluation phase, and 22 completed the evaluation phase. Compared with their baseline seizure frequency, 12 (52%) of 23 subjects entering the evaluation phase had their seizure frequency decrease by >50%. Two subjects remained seizure free during the entire evaluation period. LEV did not significantly affect plasma concentrations of any concomitant AED during this study, and no alteration of mean clinical laboratory values was observed. The most commonly reported adverse events were headache, infection, anorexia, and somnolence. CONCLUSIONS: This open-label study of adjunctive LEV therapy (at 20-40 mg/kg/day) suggests that LEV is effective, safe, and well tolerated in children ages 6-12 years with treatment-resistant partial-onset seizures. A randomized, placebo-controlled, double-blind trial of LEV adjunctive therapy in children with treatment-resistant partial-onset seizures is needed and ongoing to confirm these open-label findings.     

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.     

A placebo-controlled trial of lamotrigine add-on therapy for partial seizures in children. Lamictal Pediatric Partial Seizure Study Group

OBJECTIVE: To compare the safety and efficacy of add-on lamotrigine and placebo in the treatment of children and adolescents with partial seizures. BACKGROUND: Add-on and monotherapy lamotrigine is safe and effective in adults with partial seizures, and reports of preliminary uncontrolled trials suggest similar benefits in children. METHODS: We studied 201 children with diagnoses of partial seizures of any subtype currently receiving stable conventional regimens of antiepileptic therapy at 40 study sites in the United States and France. After a baseline observation period (to confirm that more than four seizures occurred in each of two consecutive 4-week periods), patients were randomized to add-on lamotrigine or placebo therapy. A 6-week dose-escalation period was followed by a 12-week maintenance period. RESULTS: Compared with placebo, lamotrigine significantly reduced the frequency of all partial seizures and the frequency of secondarily generalized partial seizures in these treatment-resistant patients. The most commonly reported adverse events in the lamotrigine-treated patients were vomiting, somnolence, and infection; the frequency of these and other adverse events was similar to that in the placebo-treated group, with the exception of ataxia, dizziness, tremor, and nausea, which were more frequent in the lamotrigine-treated group. The frequency of withdrawals for adverse events was similar between groups. Two patients were hospitalized for skin rash, which resolved after discontinuation of lamotrigine therapy. CONCLUSIONS: Lamotrigine was effective for the adjunctive treatment of partial seizures in children and demonstrated an acceptable safety profile.     

Efficacy and safety of levetiracetam 1000-3000 mg/day in patients with refractory partial-onset seizures: a multicenter, open-label single-arm study

PURPOSE: To evaluate the efficacy and tolerability of levetiracetam as add-on therapy in patients with refractory partial-onset seizures in a protocol designed to reflect clinical practice. METHODS: All patients in this open-label, single-arm study entered an 8-week baseline period followed by a 4-week titration period and a 12-week maintenance period. Patients initially received levetiracetam 1000 mg/day (administered bid) and could increase to 2000 mg/day after 2 weeks, and to 3000 mg/day after another 2 weeks, to obtain adequate seizure control. During the 12-week maintenance period, the dose of levetiracetam could not be increased but could be decreased once if tolerability warranted. Seizure count and adverse events were recorded by patients in a diary. Quality of life and global evaluation of disease evolution were also evaluated. RESULTS: Ninety-nine patients were enrolled and 91 completed the study. A steady dose was maintained over the last 8 weeks of treatment or longer in 84 patients, with 89.3% of these patients receiving 3000 mg/day, 9.5% receiving 2000 mg/day, and 1.2% receiving 1000 mg/day. A 35.9% median percent reduction from baseline in weekly frequency of partial-onset seizures was observed over the entire treatment period. The median partial-onset seizure count decreased from 2.3 per week during the baseline period to 1.3 per week over the treatment period. A total of 42.4% of patients were responders (> or = 50% reduction from baseline in weekly seizure frequency) over the treatment period; two patients were seizure-free from the first day of treatment throughout the treatment period. The most frequent drug-related adverse events were fatigue (27.3% of patients), somnolence (11.1%), headache (8.1%), and dizziness (8.1%). CONCLUSION: Levetiracetam as add-on therapy at doses up to 3000 mg/day effectively reduced the frequency of partial-onset seizures in patients with refractory epilepsy and was well-tolerated in this study, bridging conditions of placebo-controlled clinical trials and clinical practice.     

Efficacy and Tolerability of Vigabatrin in Children with Refractory Partial Seizures: A Single-Blind Dose-Increasing Study

Summary: The efficacy and tolerability of vigabatrin (VGB) in children with refractory partial epilepsy were assessed in a single-blind, add-on, fixed-sequence, placebo-controlled trial. After 1-month observation, the patients entered a 7-month treatment period that involved administration of placebo for 1 month followed by VGB at the initial dosage of 40 mg/kg/day, to be increased to 60 and 80 mg/kg/day at 2-month intervals if seizures persisted. Of the 46 children enrolled in the study, 7 dropped out prematurely due to lack of efficacy of the drug (n = 6) or increased seizure frequency (n = 1). In 11 patients who either became seizure-free (n = 3) or improved markedly (n = 8), treatment was completed at a dose <80 mg/kg/day. The average number of seizures per month in the 39 patients who completed the study decreased from 97 during placebo to 21,12, and 9 after 2, 4, and 6 months of VGB treatments respectively (p < 0.0001 at each time). Response to VGB remained statistically significant when dropouts were included in the evaluation. The number of patients who had <50% reduction in seizure frequency after 2, 4, and 6 months was 28, 33, and 35, respectively. Eight patients became seizure-free during the last 2 months of VGB treatment (3 at 40, 3 at 60, and 2 at 80 mg/kg/day, as compared with none during placebo treatment). Serum levels of associated antiepileptic drugs (AEDs) showed no signscant changes, except for serum phenytoin (PHT) concentration, which significantly (p < 0.01) decreased after VGB treatment. Increased appetite and sedation were observed in 17 and 11% of cases, respectively. VGB is effective in the management of refractory partial epilepsy in children, and in some patients a positive dose-response relationship appears to occur over the assessed dosing range.     

多中心、随机、双盲、安慰剂对照评价唑尼沙胺添加治疗癫(癎)部分性发作的疗效和安全性

目的 评价唑尼沙胺作为添加治疗癫(癎)部分性发作的疗效和安全性.方法 确诊为有癫(癎)部分性发作的217例癫(癎)患者,随机分配入唑尼沙胺治疗组(n=111)与安慰剂组(n=106)进行随机、双盲、安慰剂对照、多中心平行设计添加治疗.在3个月回顾性基线期后,给予患者初始剂量唑尼沙胺(100 mg/片)或安慰剂每次1片,每日1次口服,4周内递增至每次2片,每日2次.分别在治疗0、2、4、8、12和16周时进行随访.主要疗效指标为治疗结束后与基线期比较发作次数减少的中位百分比;次要疗效指标为发作次数减少大于50%的比例.同时观察研究药物的安全性与不良反应情况.结果 总发作次数减少率中位数在唑尼沙胺组为33.33%,安慰剂组为0;唑尼沙胺组总发作次数减少>50%者38例(34.23%),安慰剂组21例(19.81%),差异有统计学意义(χ3=5.7159,P=0.0168).唑尼沙胺组治疗后无发作13例(11.71%),有效25例(22.52%),临床有效率为34.23%;安慰剂组无发作5例(4.72%),有效16例(15.09%),临床有效率为19.81%,2组间比较差异有统计学意义(U=2.4701,P=0.0135).唑尼沙胺组与安慰剂组比较,其不良反应发生率差异无统计学意义,唑尼沙胺组较常见的不良反应有思睡、乏力、食欲下降、胃肠道不适、失眠和便秘.结论 唑尼沙胺作为部分性癫(癎)发作的添加药物有确定的疗效,安全耐受性较好,具有一定临床应用价值.     

多中心、随机、双盲、安慰剂对照评价普瑞巴林添加治疗部分性癫癎发作的疗效和安全性

目的 评价普瑞巴林添加治疗部分性癫（癎）发作的疗效和安全性.方法采用随机、双盲、安慰剂对照、多中心平行设计添加治疗的方法,确诊为有部分性癫（癎）发作的225例癫（癎）患者,被随机分配入普瑞巴林治疗组（114例）与安慰剂组（111例）.在6周前瞻性基线期后,采用灵活剂量的普瑞巴林（150～600 mg·d-1）添加治疗成人部分性癫（癎）发作.主要疗效指标：部分性癫（癎）发作28 d-反应率.次要疗效指标：部分性癫（癎）发作28d-减少率、临床疗效评价、16周内癫（癎）无发作和发作减少率≥50％的病例比例、第13～16周癫（癎）无发作和发作减少率≥50％的病例比例以及临床疗效总评量表评分;并观察研究药物的安全性与不良反应情况.结果 普瑞巴林组部分性癫（癎）发作28 d-反应率（-40.24±37.88）％,显著高于安慰剂组（-22.84±37.61）％（F=15.063 9,P=0.000 l）.普瑞巴林组和安慰剂组的不良事件发生率分别为60.53％和47.75％,组间无显著差异;但普瑞巴林组的不良反应发生率较安慰剂组高（45.61％ vs 23.42％,P=0.000 7）,主要不良反应有头晕、嗜睡、视物模糊、乏力等.结论 普瑞巴林组的疗效显著优于安慰剂组.普瑞巴林作为部分性癫（痈）发作的添加药物有确定的疗效,安全耐受性较好,具有一定临床应用价值.     

Adjuvant Vigabatrin in Refractory Epilepsy: A Ceiling to Effective Dosage in Individual Patients?

A double-blind, randomized, cross-over study of additional vigabatrin (γ-vinyl-GABA, VGB, 1.0 g twice daily for 6 weeks, followed by 1.5 g twice daily for 6 weeks) and matched placebo was undertaken in 24 patients with refractory epilepsy. Nineteen completed the trial satisfactorily. Fewer seizure days were reported during VGB treatment [placebo 41, VGB 23, p < 0.05, 95% confidence interval (CI) ?1.5 to ?14]. An overall reduction in median seizure numbers failed to reach statistical significance (n = 19; placebo 52, VGB 32, NS, 95% CI ?18 to + 24). Subgroup analysis, however, showed a significant reduction in partial seizures (n = 17) with 2 g VGB daily (placebo 22, VGB 13, p < 0.05, 95% CI ?0.5 to ?16.5), but not with higher dosage (placebo 28, VGB 22, NS, 95% CI ? 18 to + 11). A deterioration in control of partial seizures as compared with the equivalent placebo phase was observed when patients were changed from 2 to 3 g/day VGB (2 g VGB 13, 3 g VGB 22, p = 0.05, 95% CI 0 to +20). Loss of efficacy was noted in 3 patients, and seizure control worsened slightly in 5 others. One previously resistant patient developed a therapeutic response, and 2 other patients reported an additional useful reduction in seizures. In the remaining 8 patients, seizure frequency did not change. VGB did not appear to benefit tonic-clonic seizures. Serum VGB concentrations were higher during treatment with 3 g (15.5 ± 8.9 mg/L) daily than with 2 g (13.5 ± 11.2 mg/L). No important alterations were noted in the concentrations of concomitantly administered antiepileptic drugs (AEDs) throughout the trial. VGB is useful adjuvant therapy for treatment of partial seizures. There may be a ceiling to effective dosage. This demands individual dose titration for each patient.     

Dose-response effect of levetiracetam 1000 and 2000 mg/day in partial epilepsy

PURPOSE: To evaluate the efficacy, dose-response, tolerability, and withdrawal effects of levetiracetam (Keppra) as adjunctive therapy in adult patients with partial epilepsy. METHODS: In this European multicenter, double-blind, randomized, cross-over trial, levetiracetam 1000 or 2000 mg/day given in two divided doses was compared to placebo as add-on therapy in 324 patients with refractory partial seizures with or without secondary generalization. This trial consisted of six periods: an 8- or 12-week baseline, a treatment period A (4-week titration and 12-week evaluation), a treatment period B (4-week titration and 12-week evaluation), and a withdrawal period. During each evaluation period (A and B), patients received two of the three possible treatment regimens. RESULTS: This study provides additional information on dose-response effects and withdrawal phenomena and confirms the responder and seizure freedom rates previously reported in the parallel part of the study (Epilepsia 41 (2000) 1179-1186). Both doses of levetiracetam significantly decreased mean partial seizure frequency compared with placebo (P<0.001), and significantly more patients receiving levetiracetam had > or = 50 and > or = 75% reductions in partial seizure frequency (1000 mg, P=0.004 and P=0.043, respectively; 2000 mg P=0.001 and P<0.001, respectively). In addition, 5.5% (10/183) of patients receiving levetiracetam 1000 mg/day and 6.3% (11/175) of patients receiving levetiracetam 2000 mg/day were seizure-free during the corresponding evaluation period, compared with 1.2% (2/172) of patients on placebo. A within-patient comparison revealed a significantly greater responder rate for the higher levetiracetam dose (P=0.018). The most commonly reported adverse effects (> or = 5% and more frequent in one of the groups with levetiracetam) were headache, asthenia, infection, somnolence, pharyngitis, dizziness, and pain. No withdrawal-related adverse events were reported during the cross-titration period. CONCLUSIONS: Levetiracetam was effective and well-tolerated and decreased seizure frequency in a dose-dependent manner, with no evidence of typical withdrawal-related adverse events or rebound phenomena after withdrawal or down-titration.