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. Safety and efficacy of two pregabalin regimens for add-on treatment of partial epilepsy. Pregabalin add-on treatment: a randomized, double-blind, placebo-controlled, dose-response study in adults with partial seizures. Dose-response trial of pregabalin adjunctive therapy in patients with partial seizures. Pregabalin add-on therapy using a flexible, optimized dose schedule in refractory partial epilepsies: a double-blind, randomized, placebo-controlled, multicenter trial. Efficacy and safety of pregabalin versus lamotrigine in patients with newly diagnosed partial seizures: a phase 3, double-blind, randomised, parallel-group trial. A comparison of pregabalin, lamotrigine, and placebo as adjunctive therapy in patients with refractory partial-onset seizures. Adjuvant vigabatrin in refractory epilepsy: a ceiling to effective dosage in individual patients? Double-blind, placebo-controlled study of vigabatrin (gamma-vinyl GABA) in drug-resistant epilepsy.
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.
                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.
                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.
                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. To evaluate the efficacy, tolerability, and safety of two pregabalin regimens administered as adjunctive therapy to that of placebo in patients with medically refractory partial epilepsy.
                A multicenter, double-blind, randomized, parallel-group, placebo-controlled trial was performed. Following a prospective 8-week baseline phase, patients were randomized to 12 weeks of double-blind treatment with placebo or pregabalin 600 mg/day administered twice daily (BID) or three times daily (TID). Primary efficacy was measured as change in seizure frequency from baseline of either pregabalin regimen compared with placebo. Secondary efficacy comparisons included the proportion of patients experiencing > or =50% reduction in seizure frequency (responder rate) and median percentage change from baseline in seizure frequency. Safety/tolerability assessments included adverse events (AEs), physical and neurologic examinations, and clinical laboratory evaluation. Efficacy and safety analyses were performed on the intent-to-treat (ITT) population.
                Pregabalin treatment resulted in seizure frequency reductions: 53% for pregabalin TID (p < or = 0.0001) and 44% for pregabalin BID (p < or = 0.0001) compared with a 1% increase for placebo. Responder rates were 49% for pregabalin TID and 43% for pregabalin BID compared with 9% for placebo (p < or = 0.001). Both pregabalin regimens were similar in efficacy and tolerability. The most common AEs were dizziness, somnolence, and ataxia.
                Pregabalin administered at 600 mg/day is safe, generally well tolerated, and efficacious as adjunctive therapy for the treatment of patients with partial seizures, with or without secondary generalizations. This dose can be administered on a twice daily or three times daily schedule with similar efficacy and tolerability results. To evaluate pregabalin (PGB), 150 mg/day, and PGB, 600 mg/day, as an add-on treatment for patients with refractory partial seizures concurrently treated with one to three anticonvulsants (AEDs).
                An international (13 countries), multicenter (45 centers), 12-week, double-blind, randomized study in which patients with partial seizures received placebo (n = 96); PGB, 150 mg/day (n = 99); or PGB, 600 mg/day (n = 92); given 3 times a day (t.i.d.). The primary efficacy criterion was reduction in seizure frequency during treatment as compared with baseline, as measured by RRatio, the symmetrical percentage change in seizure rates determined from daily seizure diaries. The RRatio between the 8-week baseline (pretreatment phase) and the 12-week treatment period were compared between each of the PGB groups and the placebo group by using an analysis of variance analysis of the intent-to-treat population.
                PGB, 150 mg/day and 600 mg/day, were both significantly more effective than placebo in reducing the RRatio [-11.5 (p = 0.0007) and -31.4 (p < or = 0.0001), respectively, vs. 0.9]. These RRatio values correspond to seizure-frequency reductions from baseline of -1.8, 20.6, and 47.8% for placebo, 150 mg/day, and 600 mg/day, respectively. PGB efficacy was significantly dose related (p < or = 0.0001). Secondary efficacy variables corroborated the findings of the primary analysis. Significantly more patients were responders (> or =50% reduction in seizure frequency) in the PGB, 600 mg/day (43.5%), group than in the placebo group (6.2%) (p < or = 0.001). PGB was well tolerated. Dose-related, treatment-emergent adverse events (> or =10%), mostly mild or moderate in intensity, were somnolence, dizziness, ataxia, diplopia, and weight gain. The withdrawal rate due to adverse events was 10% of patients at 150 mg/day and 18.5% of patients at 600 mg/day, compared with 6.2% of patients receiving placebo.
                PGB, 150 mg/day and 600 mg/day, is highly effective and well-tolerated add-on therapy in patients with partial seizures. Pregabalin is an alpha(2)-delta ligand that has anxiolytic, analgesic, and anticonvulsant properties.
                To establish the efficacy, safety, and tolerability of pregabalin administered twice-daily (BID) without dose titration as adjunctive treatment in patients with partial seizures and to confirm the dose-response relationship.
                This 76-center, double-blind, randomized, placebo-controlled, parallel-group study consisted of an 8-week baseline and a 12-week double-blind phase. Patients with refractory partial seizures on one to three antiepileptic drugs were randomly assigned to one of five treatment groups (placebo or 50, 150, 300, and 600 mg/d pregabalin, all administered BID). Efficacy was assessed using seizure frequency reduction and responder rate (> or =50% seizure reduction from baseline). Pharmacokinetic parameters were estimated.
                A total of 453 patients were included in the intent-to-treat analysis. The median baseline seizure rate was 10 per month. Seizure frequency reductions from baseline were 7% (placebo; n = 100), 12% (50 mg/d; n = 88), 34% (150 mg/d; n = 86), 44% (300 mg/d; n = 90), and 54% (600 mg/d; n = 89). Responder rates (> or =50% seizure reduction) were 14% (placebo), 15% (50 mg/d), 31% (150 mg/d), 40% (300 mg/d), and 51% (600 mg/d). Discontinuation rates due to adverse events were 5% (placebo), 7% (50 mg/d), 1% (150 mg/d), 14% (300 mg/d), and 24% (600 mg/d). The 150-, 300-, and 600-mg/d pregabalin groups were associated with greater reductions in seizures (p < or = 0.0001) and greater responder rates compared with the placebo group (p < or = 0.006). There was a favorable dose-response trend for both seizure reductions (p < or = 0.0001) and responder rate (p < or = 0.001).
                Adjunctive therapy with pregabalin 150, 300, and 600 mg/d, given in twice-daily doses without titration, is significantly effective and well tolerated in the treatment of patients with partial seizures as demonstrated in patients with refractory partial seizures. 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.
                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 (>or=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.
                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 (>or=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 <or=20).
                PGB was effective and easily tolerable as add-on treatment in an Asian population with refractory partial-onset seizures. Efficacious and safe monotherapy options are needed for adult patients with newly diagnosed epilepsy. As an adjunctive treatment for partial seizures, pregabalin compares favourably with lamotrigine and is an effective, approved treatment. We studied the efficacy and safety of pregabalin as monotherapy, using a design that complied with European regulatory requirements and International League Against Epilepsy guidelines.
                This phase 3, double-blind, randomised, non-inferiority study compared the efficacy and tolerability of pregabalin and lamotrigine monotherapy in patients with newly diagnosed partial seizures at 105 centres, mostly in Europe and Asia. Randomisation to treatment groups (1:1 ratio) was by a computer-generated pseudorandom code (random permuted blocks), with patients sequentially assigned numbers by telephone. Investigators, site staff, and patients were masked to the assigned treatment. After randomisation, patients were titrated to either 75 mg oral pregabalin or 50 mg oral lamotrigine twice daily during a 4-week dose-escalation phase, followed by a 52-week efficacy assessment phase during which the daily dose could be increased as needed to a maximum of 600 mg and 500 mg, respectively. The primary efficacy endpoint was the proportion of patients who remained seizure-free for 6 or more continuous months during the efficacy assessment phase; analysis included all patients who were randomly assigned to treatment groups and received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, number NCT00280059.
                660 patients were randomly assigned to treatment groups (330 pregabalin, 330 lamotrigine), of whom 622 entered the efficacy assessment phase (314 pregabalin, 308 lamotrigine). Fewer patients in the pregabalin group than in the lamotrigine group became seizure-free for 6 or more continuous months (162 [52%] vs 209 [68%]; difference in proportion, -0·16, 95% CI -0·24 to -0·09). The overall incidence of adverse events was similar between the groups and consistent with that in previous studies; dizziness (55 [17%] vs 45 [14%] patients), somnolence (29 [9%] vs 14 [4%]), fatigue (27 [8%] vs 19 [6%]), and weight increase (21 [6%] vs 7 [2%]) were numerically more common in the pregabalin group than in the lamotrigine group.
                Pregabalin has similar tolerability but seems to have inferior efficacy to lamotrigine for the treatment of newly diagnosed partial seizures in adults. Inferior efficacy of pregabalin might have been attributable to limitations in the study design, as treatment doses might have not been optimised adequately or early enough.
                Pfizer Inc.
                Copyright © 2011 Elsevier Ltd. All rights reserved. This study assessed the comparative efficacy of pregabalin for refractory partial seizures.
                Four-hundred and thirty-four patients with partial seizures were randomized to pregabalin, lamotrigine, or placebo as adjunctive therapy for 17 weeks of double-blind treatment. In phase I (11 weeks), pregabalin was titrated over 1 week and lamotrigine over 5 weeks to fixed dosages of 300mg/day for both. In phase II (6 weeks), patients not yet seizure-free were increased to pregabalin 600mg/day or lamotrigine 400mg/day.
                During phase I, there was a nonsignificant trend toward a greater reduction in seizures with pregabalin versus placebo and lamotrigine. Across the 17 weeks of treatment, pregabalin showed a median percentage reduction from baseline in seizure frequency of -20.0% (p=.001) versus placebo, and -9.7% (p=.080) versus lamotrigine. The responder rate (> or =50% reduction in seizure frequency) for pregabalin exceeded that of placebo (36% vs 21%; p=.007) and lamotrigine (36% vs 24%; p=.04). Adverse events were consistent with the known safety profiles of pregabalin and lamotrigine.
                Pregabalin was demonstrated to be noninferior to lamotrigine in the treatment of refractory partial seizures. Overall conclusions were complicated by an unusually large and heterogeneous placebo response.
                Copyright 2010. Published by Elsevier B.V. A double-blind, randomized, cross-over study of additional vigabatrin (gamma-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. Vigabatrin (GVG) (3 g/day) and placebo were compared as an add-on to standard therapy in therapy-resistant epileptic patients using a double-blind crossover design with randomized treatment allocation. Twenty-three patients entered the trial, with four dropping out due to either increased seizure frequency following the cross-over from GVG to placebo (n = 1), intolerance to GVG therapy (n = 2), or poor seizure record (n = 1). Of the 19 patients who completed the study, 17 had partial seizures, eight of whom had secondary generalization and two who had primary generalized seizures. Compared with placebo, GVG was associated with a significant reduction in seizure frequency (p less than 0.01), with 11 of 19 patients experiencing greater than 50% reduction in weekly seizure occurrence, two showing a 25-50% reduction, four unchanged, and two showing an increase in seizures. Global efficacy ratings were greater in the GVG period for 15 patients (p less than 0.05) compared with one in whom there was no period difference and two in whom ratings were higher in the placebo period. Fourteen of the 19 patients indicated a preference for the GVG period. Adverse effects observed during GVG treatment were generally mild and consisted of drowsiness, confusion, nausea, irritability, and constipation. No clinically significant alterations in laboratory test results were observed. No treatment-related changes in plasma concentrations of concomitant antiepileptic drugs were noted. These results confirm the antiepileptic efficacy of oral GVG in refractory epileptics.
Pregabalin, when used as an add-on drug for treatment-resistant partial epilepsy, is significantly more effective than placebo at achieving a 50% or greater seizure reduction and significantly increasing seizure freedom. Results demonstrate efficacy for doses from 150 mg/day to 600 mg/day, with increasing effectiveness at 600 mg doses. The trials included in this review were of short duration and longer-term trials are needed to inform clinical decision making better.