Pregabalin add‐on therapy using a flexible,optimized dose schedule in refractory partial epilepsies: A double‐blind,randomized, placebo‐controlled,multicenter trial

Purpose: To evaluate the efficacy and safety of pregabalin (PGB) as adjunctive therapy, using a flexible‐dosing schedule in Korean patients with refractory partial‐onset seizures. Methods: This randomized, double‐blind (DB), placebo‐controlled trial consists of a 6‐week baseline, a 12‐week DB treatment, and a 1‐week taper phase. Patients having recurrent partial seizures (≥4 seizures during baseline phase) under adequate pharmacotherapy were recruited to be randomized to PGB or placebo (PLC) in a 2 to 1 ratio. Starting dose was 150 mg/day, increased every 2 weeks by 150‐mg/day increments up to maximum dose of 600 mg/day. The primary efficacy parameter was response ratio (RRatio) for all partial seizures. Results: A total of 178 patients (119 in PGB, 59 in PLC) were assigned to the study. Median daily doses of PGB and PLC were 367 and 420 mg/day, respectively. RRatio least squares (LS) mean was ?35.8 in the PGB group and ?23.2 in the PLC group, with estimated difference in RRatios being ?12.6 [95% confidence interval (CI): ?22.7 to ?2.5, p = 0.015] in the intent‐to‐treat (ITT) population. Analysis of secondary efficacy measures showed a general trend favoring PGB over PLC. Seventy‐seven patients (64.7%) in the PGB group and 18 patients (30.5%) in the PLC group developed adverse events (AEs) related to the study drug. Seven patients (5.9%) in the PGB group discontinued the study prematurely because of AEs. In the post hoc analysis, a significant weight gain (≥7% of baseline body weight) was found in 24.8% of patients taking PGB, which was more frequent in patients with a lower body mass index (BMI ≤20). Discussion: PGB was effective and easily tolerable as add‐on treatment in an Asian population with refractory partial‐onset seizures.     

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.     

Efficacy and tolerability of adjunctive brivaracetam in adults with uncontrolled partial‐onset seizures: A phase IIb,randomized, controlled trial

Purpose: To evaluate the efficacy and tolerability of adjunctive brivaracetam (BRV), a novel high‐affinity synaptic vesicle protein 2A ligand that also displays inhibitory activity at neuronal voltage‐dependent sodium channels, in adult epilepsy patients with uncontrolled partial‐onset seizures. Methods: A phase IIb, double‐blind, randomized, placebo‐controlled, parallel‐group, dose‐ranging study (N01114; NCT00175929) was conducted in patients aged 16–65 years. To be included in the study, patients were required to have experienced four or more partial‐onset seizures during a 4‐week prospective baseline, despite treatment with 1–2 concomitant antiepileptic drugs. Patients were randomized in a ratio of 1:1:1 to receive BRV 50 mg/day (BRV50), 150 mg/day (BRV150), or placebo. A 3‐week up‐titration period was followed by a 7‐week maintenance period (total treatment period of 10 weeks). Key Findings: A total of 157 patients were randomized (intent‐to‐treat [ITT] population; BRV50 n = 53, BRV150 n = 52, placebo n = 52) and overall 148 (94.3%) completed the study. The percent reduction in baseline‐adjusted partial‐onset seizure frequency/week over placebo during the 7‐week maintenance period (primary efficacy outcome) did not reach statistical significance (14.7% for BRV50 [p = 0.093] and 13.6% for BRV150 [p = 0.124]). However, during the entire 10‐week treatment period a statistically significant difference was observed for both BRV groups (17.7% for BRV50 [p = 0.026] and 16.3% for BRV150 [p = 0.043]). The median percent reduction from baseline in partial‐onset seizure frequency/week during the maintenance period was 38.2% for BRV50 (p = 0.017) and 30.0% for BRV150 (p = 0.113) versus 18.9% in the placebo group. During the treatment period, this was 34.9% for BRV50 (p = 0.004) and 28.3% for BRV150 (p = 0.070) compared with 16.3% for placebo. Fifty percent responder rates during the maintenance period were 23.1% for placebo compared with 39.6% for BRV50 (odds ratio [OR] 2.17, p = 0.077) and 33.3% for BRV150 (OR 1.66, p = 0.261). During the treatment period, 50% responder rates were 17.3% for placebo compared with 35.8% for BRV50 (OR 2.69, p = 0.038) and 30.8% for BRV150 (OR 2.15, p = 0.114). Nine patients were free from partial‐onset seizures during the 10‐week treatment period (five patients [9.4%] in the BRV50 group and three [5.8%] in the BRV150 group compared with one patient [1.9%] in the placebo group). Treatment‐emergent adverse events (TEAEs) reported during the treatment period were mostly mild‐to‐moderate with similar incidence across treatment groups (BRV50 36/53, 67.9%; BRV150 35/52, 67.3%; placebo 37/52, 71.2%). The most frequently reported TEAEs in BRV groups were headache, fatigue, nasopharyngitis, nausea, somnolence, and dizziness, although nausea had a higher incidence in the placebo group. Significance: In this double‐blind, placebo‐controlled, phase IIb study of adjunctive BRV (50 and 150 mg/day) in adults with uncontrolled partial‐onset seizures, the primary efficacy analysis did not reach statistical significance; however, statistically significant differences compared with placebo were observed on several secondary efficacy outcomes. BRV was well tolerated.     

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.     

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.     

Adjunctive pregabalin for uncontrolled partial-onset seizures: findings from a prospective audit

Stephen LJ, Parker P, Kelly K, Wilson EA, Leach V, Brodie MJ. Adjunctive pregabalin for uncontrolled partial‐onset seizures: findings from a prospective audit.
Acta Neurol Scand: 2011: 124: 142–145.
© 2011 John Wiley & Sons A/S. Aims – Pregabalin (PGB) was licensed in Europe as an add‐on antiepileptic drug (AED) for the treatment of partial‐onset seizures in 2004. This audit assessed the response to adjunctive PGB in patients with uncontrolled seizures. Methods – PGB was titrated in 135 patients [73 men; 62 women, aged 18–76 (median 44 years) until one of the following occurred: ≥6 months’ seizure freedom, ≥50% or <50% seizure reduction over 6 months; PGB withdrawal because of adverse effects, lack of efficacy or both. Results – Of the 135 patients, 14 (10.4%) became seizure‐free for ≥6 months (median PGB dose 300 mg/day; range 75–600 mg). A ≥ 50% seizure reduction occurred in 33 (24.4%) patients; 20 (14.8%) had <50% reduction. PGB was withdrawn in 68 (50.4%) (40 adverse effects, seven lack of efficacy and 21 both). Commonest problems resulting in withdrawal were sedation (n = 18), weight gain (n = 14) and ataxia (n = 9). There was a positive correlation between increasing dose and weight gain (r = 0.42, P = 0.045). Conclusions – Add‐on PGB benefited 50% of patients, but only 10% achieved 6 months’ seizure freedom. Adverse effects, most commonly sedation, dose‐related weight gain and ataxia, led to drug discontinuation by 45%. Prospective audits of novel AEDs are a useful adjunct to randomized, controlled trials in managing epilepsy.     

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.     

Gabapentin (Neurontin) as Add-on Therapy in Patients with Partial Seizures: A Double-Blind,Placebo-Controlled Study

Summary: A multicenter, double-blind, randomized, placebo-controlled study evaluated the efficacy and safety of gabapentin (Neurontin, GBP) as add-on therapy in 272 patients with refractory partial seizures who were receiving one to two standard antiepileptic drugs (AEDs). Efficacy assessments compared the frequency of partial seizures during the 12-week treatment phase (T) and the 12-week baseline period (B). The primary analysis compared data for patients receiving GBP 900 mg/day with placebo; the GBP 1,200-mglday group provided doseresponse data. Efficacy criteria were percentage of change in seizure frequency (PCH), responder rate (percentage of patients with ≥50% reduction in seizure frequency), and response ratio, where RRatio = (T B)/(T + B). Median PCH was–21.8% in the 900-mg/day group and ?17.8% in the 1,200-mg/day group as compared with ?0.3% in the placebo group. Responder rate was 22.9% in the 900-mg/day group and 10.1% in the placebo group (p = 0.020, Fisher's exact test). Adjusted mean Rratio was-0.136 in the 900-mg/day group and ?0.025 in the placebo group (p = 0.0046, analysis of variance ANOVA). Results showed slightly greater improvement for the 1,20-mg/day than for the 900-mg/day group (RRatio =?0.157, responder rate 28.0%). Adverse events (AE) occurred in 69% of patients in the 900-mg/day group and in 64% in the 1,200-mg/day group as compared with 52% in patients receiving placebo as add-on therapy. The most frequent AE among patients treated with GBP were somnolence, dizziness, and fatigue. Clinical laboratory evaluations showed no clinically important trends and no evidence of hepatic or hematopoietic effects. GBP is safe and effective in treating some patients with refractory partial seizures.     

Clinical Efficacy of Topiramate as Add-On Therapy in Refractory Partial Epilepsy: The European Experience

Summary: In three randomized, double-blind, placebo-controlled add-on European trials, target daily topiramate (TPM) dosages of 400, 600, and 800 mg/day (200, 300, and 400 mg bid) were evaluated in adults with refractory partial seizures with or without becoming secondarily generalized. Median reductions from baseline in monthly seizure rate were 41% with TPM 400 mg/day vs. 1% with placebo ( n = 0.065), 46% with TPM 600 mg/day compared to -12% (a 12% increase) with placebo ( p ≤ 0.005), and 36% with TPM 800 mg/day versus –18% (an 18% increase) with placebo ( p ≤ 0.001). Differences between TPM and placebo with respect to percent responders (percent of patients demonstrating a 50% or greater reduction in seizures) significantly favored TPM ( p ≤ 0.05) at all three target dosages. Significant reductions in secondarily generalized tonic-clonic seizures compared to placebo were also observed with 400 mg/day ( p = 0.002) and 800 mg/day ( p < 0.05) of TPM. TPM appears to be a promising new antiepileptic drug for use as adjunctive therapy in adults with refractory partial epilepsy.     

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.     

Efficacy and safety of oral lacosamide as adjunctive therapy in adults with partial-onset seizures

PURPOSE: To evaluate the efficacy and safety of lacosamide when added to 1 or 2 antiepileptic drugs (AEDs) in adults with uncontrolled partial-onset seizures, and assess plasma concentrations of concomitant AEDs to determine any potential for drug interactions. METHODS: During this multicenter, double-blind, placebo-controlled trial, patients were randomized to placebo or lacosamide 200, 400, or 600 mg/day after an 8-week baseline period. Lacosamide was titrated in weekly increments of 100 mg/day over 6 weeks and maintained for 12 weeks. Results were analyzed on an intention-to-treat basis. RESULTS: Four hundred eighteen patients were randomized and received trial medication; 312 completed the trial. The median percent reduction in seizure frequency per 28 days was 10%, 26%, 39%, and 40% in the placebo, lacosamide 200, 400, and 600 mg/day treatment groups, respectively. The median percent reduction in seizure frequency over placebo was significant for lacosamide 400 mg/day (p=0.0023) and 600 mg/day (p=0.0084). The 50% responder rates were 22%, 33%, 41%, and 38% for placebo, lacosamide 200, 400, and 600 mg/day, respectively. The 50% responder rate over placebo was significant for lacosamide 400 mg/day (p=0.0038) and 600 mg/day (p=0.0141). Adverse events that appeared dose-related included dizziness, nausea, fatigue, ataxia, vision abnormal, diplopia, and nystagmus. Lacosamide did not affect mean plasma concentrations of concomitantly administered AEDs. CONCLUSIONS: In this trial, adjunctive lacosamide significantly reduced seizure frequency in patients with uncontrolled partial-onset seizures. Along with favorable pharmacokinetic and tolerability profiles, these results support further development of lacosamide as an AED.     

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.     

N,N dimethylglycine and epilepsy

Nineteen institutionalized patients with frequent seizures (group average two to three per day; seizure types--generalized, akinetic/myoclonic), were treated randomly with either placebo or N,N dimethylglycine (DMG) for 28 days. Dosage was 300 mg/day for the first 14 days and then 600 mg/day. Plasma levels were measured at baseline, days 2, 5, 8, 15, 22, 30, and 1 and 2 weeks after the study ended. No differences in seizure frequency were noted between placebo and DMG or between baseline and test conditions. No toxicity was noted.     

Adjunctive lacosamide for focal epilepsy: an open‐label trial evaluating the impact of flexible titration and dosing on safety and seizure outcomes

Aims. To evaluate the safety and effectiveness of lacosamide in a real‐life setting with the use of a flexible dose titration schedule and individualised maintenance doses up to the maximum approved dose of 400 mg/day. Methods. Adults with a diagnosis of focal seizures, with or without secondary generalization, were enrolled in this open‐label Phase IV trial (NCT01235403). Lacosamide was initiated at 100 mg/day (50 mg bid) and uptitrated over a 12‐week period to 200, 300 or 400 mg/day, based on safety and seizure control. Although dose increases were to be in increments of 100 mg/day, intermediate doses were permitted at each escalation step for one week for patients known to be particularly sensitive to starting new AEDs. After receiving a stable, effective dose for three weeks, patients entered the 12‐week maintenance period. Primary outcomes were incidence of treatment‐emergent adverse events (TEAEs) and withdrawal due to TEAEs. Seizure outcomes, all secondary, were median focal seizure frequency, ≥50% reduction in focal seizure frequency, and seizure freedom. Results. One hundred patients with a mean age of 44 years were enrolled and 74 completed the trial. The incidence of TEAEs was 64.0% (n=100), with the most frequently reported (≥5% of patients) being dizziness, headache, and asthenia. Fourteen patients withdrew due to TEAEs, most frequently due to dizziness (six patients; 6.0%), vomiting (two patients; 2%), and tremor (two patients; 2%). Among patients with baseline and maintenance phase seizure data (n=75), median reduction in focal seizure frequency from baseline was 69.7% and the ≥50% responder rate was 69.3%. Among 74 patients who completed the maintenance phase, 21 (28.4%) were seizure‐free. Conclusion. Flexible lacosamide dosing in this open‐label trial was associated with a favourable tolerability and safety profile; the nature of the TEAEs was consistent with that observed in previous pivotal trials. Treatment with lacosamide was also associated with effective seizure control.     

Oxcarbazepine placebo-controlled, dose-ranging trial in refractory partial epilepsy

PURPOSE: The goal of the study was to evaluate the safety and efficacy of a broad oxcarbazepine (OXC) dosage range (600, 1200, and 2400 mg/d) as adjunctive therapy for uncontrolled partial seizures and to determine the relationship between trough plasma 10-monohydroxy derivative concentrations and OXC safety and efficacy. METHODS: This multinational, multicenter, randomized, 28-week, double-blind, placebo-controlled, four-arm, parallel-group trial enrolled 694 patients aged 15-65 years with uncontrolled partial seizures with or without secondarily generalized seizures. The primary efficacy variable was percentage change in seizure frequency per 28 days relative to baseline. RESULTS: The median reduction in seizure frequency was 26%, 40%, 50%, or 8% for patients receiving 600, 1200, or 2400 mg/d OXC or placebo, respectively (all p < or = 0.0001). Of patients in the 600, 1200, or 2400 mg/d OXC groups, 27%, 42%, and 50% respectively, had more than 50% reduction in seizure frequency compared with 13% for placebo (all p < 0.001). Higher plasma 10-monohydroxy derivative concentrations were associated with larger decreases in seizure frequency (p = 0.0001). During the double-blind treatment phase, 84%, 90%, 98%, and 76% of patients receiving 600, 1200, or 2400 mg/d OXC or placebo, respectively, reported one or more adverse events. The most common adverse events were related to the nervous and digestive systems. CONCLUSIONS: OXC is safe and effective as adjunctive therapy in patients with uncontrolled partial seizures. OXC 600 mg/d was the minimum effective dosage; effectiveness of OXC increased with dose. The rapid and fixed titration to high doses was associated with an increased risk of adverse events, which could potentially be reduced by adjusting concomitant antiepileptic medication and by using a slower, flexible OXC titration schedule.     

Retigabine as adjunctive therapy in adults with partial-onset seizures: Integrated analysis of three pivotal controlled trials

We assessed the efficacy and tolerability of retigabine (RTG; international non-proprietary name)/ezogabine (EZG; US adopted name) as adjunctive therapy in adults with partial-onset seizures in an integrated analysis of three trials. Studies 205, 301 (NCT00232596), and 302 (NCT00235755) were randomized, double-blind, placebo-controlled studies in adults having ≥4 partial-onset seizures per 28 days and receiving 1-3 antiepileptic drugs with/without vagus nerve stimulator. Patients underwent titration to RTG/EZG 600, 900, or 1200mg/day or to placebo followed by 8 or 12 weeks maintenance. For efficacy analyses, placebo was compared with RTG/EZG 600 and 900mg/day in Studies 205 and 302, and RTG/EZG 1200mg/day in Studies 205 and 301. Responder rates (≥50% reduction in baseline seizure frequency) were 35% and 45% for RTG/EZG 600 and 900mg/day, respectively (placebo=21%; p<0.001), and 50% for RTG/EZG 1200mg/day (placebo=24%, p<0.001). Reductions in 28-day total partial-seizure frequency (medians: placebo=14%; 600mg/day=26%, p=0.003; 900mg/day=37%, p<0.001; placebo=15%; 1200mg/day=39%, p<0.001) were significantly greater with all RTG/EZG doses vs. placebo from baseline to the double-blind phase, and similarly during the maintenance phase. The most commonly reported (>10%) treatment-emergent adverse events were dizziness, somnolence, headache, and fatigue. RTG/EZG demonstrated efficacy and was generally tolerated as adjunctive therapy in adults with partial-onset seizures in this integrated analysis.     

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.     

Evaluation of adjunctive perampanel in patients with refractory partial‐onset seizures: Results of randomized global phase III study 305

Purpose: To assess the efficacy and safety of once‐daily doses of perampanel 8 and 12 mg when added to 1–3 concomitantly administered, approved antiepileptic drugs (AEDs) in patients with uncontrolled partial‐onset seizures. Methods: Study 305 was a multicenter, double‐blind, placebo‐controlled trial in patients aged 12 years and older with ongoing seizures despite prior therapy with at least two AEDs, and currently receiving 1–3 AEDs. Equal randomization to once‐daily oral perampanel 8 or 12 mg, or placebo was performed. Patients entered a 19‐week double‐blind treatment phase comprising a 6‐week titration period, with weekly 2‐mg dose increments, followed by a 13‐week maintenance period. Primary efficacy end points were the responder rate (proportion of patients who had a ≥50% reduction in seizure frequency during treatment per 28 days relative to baseline), and the percent change in seizure frequency per 28 days relative to pre‐perampanel baseline. A secondary end point was percent change in the frequency of complex partial plus secondarily generalized seizures. Adverse events (AEs) were monitored throughout the study. Key Findings: Three hundred eighty‐six patients were randomized and treated with study medication. Of these, 321 patients completed the study. The 50% responder rates (intent‐to‐treat analysis) were 14.7%, 33.3%, and 33.9%, respectively, for placebo, perampanel 8 mg, and perampanel 12 mg, with significant improvements over placebo for both perampanel 8 mg (p = 0.002) and 12 mg (p < 0.001). The median percent change from baseline in seizure frequency per 28 days (intent‐to‐treat analysis) was ?9.7%, ?30.5%, and ?17.6% for placebo, 8 mg, and 12 mg, respectively, with significant reductions compared with placebo for both 8 mg (p < 0.001) and 12 mg (p = 0.011). For complex partial seizures plus partial seizures that secondarily generalized, the median percent change in frequency was ?32.7% (8 mg), ?21.9 (12 mg), and ?8.1% (placebo), with significant reductions for both 8 mg (p < 0.001) and 12 mg (p = 0.005). The most frequent (occurring in ≥10% of patients in any treatment group) treatment‐emergent AEs were dizziness, somnolence, fatigue, and headache, with an apparent dose effect suggested for all except headache. Significance: This phase III trial demonstrated that adjunctive treatment with once‐daily perampanel at 8 mg and 12 mg was effective in improving seizure control in patients 12 years and older with refractory partial‐onset seizures. These study results also demonstrated that once‐daily doses of 8 mg and 12 mg were safe and acceptably tolerated in this study. Perampanel demonstrated a favorable risk/benefit ratio in this population.     

Corrigendum

In Volume 10, Supplement 1, February 2008, this Abstract was omitted from the Poster Session. The correct citation for the Abstract is Bipolar Disord 2008; 10 (Suppl. 1). We apologize for this error. A DOUBLE‐BLIND, PLACEBO‐CONTROLLED STUDY WITH ACUTE AND CONTINUATION PHASE OF QUETIAPINE AND LITHIUM IN ADULTS WITH BIPOLAR DEPRESSION (EMBOLDEN I) AH Young^a, A Carlsson^b, B Olausson^b, B Paulsson^b and M Brecher^{c a}Department of Psychiatry, Institute of Mental Health, The University of British Columbia, Vancouver, Canada, ^bAstraZeneca, Södertälje, Sweden, ^cAstraZeneca Pharmaceuticals LP, Wilmington, DE, USA Background and aims: Evaluate the efficacy and tolerability of quetiapine and lithium monotherapy for major depressive episodes in bipolar disorder during an acute 8‐week period and up to 52‐week continuation phase. Methods: A total of 802 patients (499 bipolar I, 303 bipolar II) were randomized to quetiapine 300 mg/day (n = 265), quetiapine 600 mg/day (n = 268), lithium 600 mg/day (n = 136), or placebo (n = 133) for 8 weeks. Primary endpoint was change from baseline to 8 weeks in MADRS total score. After 8 weeks, patients with MADRS ≤ 12 and YMRS ≤ 12 entered a 26–52‐week continuation phase of quetiapine (300 mg/day or 600 mg/day) or placebo. Patients on lithium received 300 mg/day of quetiapine (results of continuation phase not included here and to be presented separately). Results: LSM MADRS score change at 8 weeks was ?15.36 (quetiapine 300 mg/day), ?16.10 (quetiapine 600 mg/day), ?13.60 (lithium), and ?11.81 (placebo; p < 0.001 for both quetiapine doses, p = 0.123 for lithium, versus placebo; LOCF ANCOVA). Quetiapine (both doses)‐treated, but not lithium‐treated, patients showed significantly greater improvements (p ≤ 0.05) in MADRS response and remission rates, HAM‐D, CGI‐BP‐S, CGI‐BP‐change, and HAM‐A at Week 8 versus placebo; MADRS item 10 (suicidal thoughts) improved with quetiapine 600 mg/day versus placebo (p = 0.013). Most common adverse events considered drug‐related included somnolence, dry mouth, and dizziness with quetiapine (both doses) and nausea with lithium. Conclusions: Quetiapine (300 mg/day or 600 mg/day) was more effective than placebo for the treatment of acute depressive episodes in bipolar I and bipolar II disorder. Quetiapine treatment was generally well tolerated.     

Pregabalin in partial seizures: a pragmatic 21‐week,open‐label study (PREPS)

Background and purpose: Pregabalin has demonstrated efficacy in controlled trials as adjunctive treatment in patients with refractory seizures. Methods: This open‐label, 21‐week study in adults with at least two partial seizures in the last 2 months, who were inadequately controlled with one to three antiepileptic drugs, evaluated pregabalin 150–600 mg/day (dosed twice daily). The study comprised a prospective or retrospective 8‐week baseline phase, and 9‐week dose optimization and 12‐week maintenance periods. The primary assessment was the mean percentage change in 28‐day seizure frequency between baseline and end‐point (last 12 weeks of treatment, last observation carried forward, modified intention‐to‐treat population). Results: Four hundred and seventy‐six patients from Europe were included in this study (51% men; mean age/epilepsy duration 40.1/24.1 years). The median baseline seizure frequency was 5.5/28 days. Amongst the patient population, 78% completed the 21‐week treatment period; 7% discontinued for lack of efficacy and 12% because of adverse events (AEs). The mean last pregabalin dose was 359 mg/day. The mean (95% CI) reduction in seizure frequency was 36% (31%; 41%). The median reduction was 33%, and 39% of patients had a ≥50% reduction in seizure frequency. There were 19% and 8% of patients free of seizures during their last 4 and 12 weeks of treatment, respectively. The three most common AEs were dizziness (17%), somnolence (13%) and weight increase (13%). Conclusions: This open‐label study of pregabalin demonstrated efficacy that was consistent with that observed in previous controlled epilepsy trials. Pregabalin was well tolerated. The AE profile was also consistent with that reported in previous trials.