A Study of the Efficacy and Safety of Topiramate in Epilepsy Patients With Primary Generalized Tonic-clonic Seizures
The purpose of this study is to evaluate the efficacy and safety of topiramate as an add-on therapy in epilepsy patients with uncontrolled primary generalized tonic-clonic seizures, who are taking 1 or 2 standard antiepileptic drugs.
Epilepsy is a disease characterized by seizures, which are abnormal electrical discharges in the brain that temporarily disrupt normal brain function. Seizures are classified as "generalized," involving all or most of the brain at the same time, or "partial onset," starting in one area of the brain. Generalized tonic-clonic seizures are also referred to as grand mal seizures and are common in people with generalized epilepsy in which the cause is not known. In a tonic-clonic seizure, the person loses consciousness, the body stiffens (tonic phase), and then the individual falls to the ground. This is followed by jerking movements in which the muscles contract and relax quickly (clonic phase). After a minute or two, the jerking movements usually stop, and the person regains consciousness. Antiepileptic medications, such as topiramate, are selected based on a patient's seizure type. Topiramate is a drug that is currently widely used for the treatment of seizures in adults and pediatric patients (2 to 16 years of age). This is a randomized, double-blind, parallel-group, placebo-controlled study to evaluate the effectiveness and safety of topiramate as an add-on therapy in patients with Primary Generalized Tonic-Clonic (PGTC) seizures. The study is in two phases: baseline (8 weeks) and double-blind treatment (20 weeks). Patients are given diaries to record information about their seizures during the phases of the study. During the baseline phase, the patient continues to receive a constant dosage of one or two antiepileptic drugs they have been taking. In the double-blind phase, patients are randomly assigned to either topiramate or placebo. The double-blind phase is divided into two periods: titration, in which the topiramate dose is gradually increased (8 weeks) (patient's antiepileptic medication continues; this dose remains the same) and stabilization (12 weeks). The dose of both topiramate and the patient's antiepileptic drug remain constant during the stabilization period. Based on the investigator's judgment, patients completing the double-blind treatment could enter a long-term extension phase of the study to continue treatment. The primary assessment of effectiveness is the percent reduction in primary generalized tonic-clonic seizure rates from baseline to the double-blind phase. Safety assessments include the frequency of adverse events during the study, results of clinical laboratory tests (hematology, biochemistry, and urinalysis), measurements of vital signs and body weight, physical examination and electrocardiogram (ECG) findings, plasma levels of topiramate and other study antiepileptic drugs, and neurological examinations. The study hypothesis is that topiramate as an add-on is superior to placebo in reducing the seizure rate from baseline to the double-blind phase of the study. Topiramate (25 mg or 100 mg tablets) or placebo, taken by mouth, starting at a dose of 25 or 50mg/day, gradually increasing to a maximum daily dose of 175 mg to 400 mg (based on body weight) or to a maximum tolerated dose (whichever dose is less). Maximum dosage continues for 12 weeks.
Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double-Blind, Primary Purpose: Treatment
Johnson & Johnson Pharmaceutical Research & Development, L.L.C.
Results (where available)
- Source: http://clinicaltrials.gov/show/NCT00236418
- Information obtained from ClinicalTrials.gov on July 15, 2010
Medical and Biotech [MESH] Definitions
Myoclonic Epilepsy, Juvenile
A disorder characterized by the onset of myoclonus in adolescence, a marked increase in the incidence of absence seizures (see EPILEPSY, ABSENCE), and generalized major motor seizures (see EPILEPSY, TONIC-CLONIC). The myoclonic episodes tend to occur shortly after awakening. Seizures tend to be aggravated by sleep deprivation and alcohol consumption. Hereditary and sporadic forms have been identified. (From Adams et al., Principles of Neurology, 6th ed, p323)
A disorder characterized by recurrent episodes of paroxysmal brain dysfunction due to a sudden, disorderly, and excessive neuronal discharge. Epilepsy classification systems are generally based upon: (1) clinical features of the seizure episodes (e.g., motor seizure), (2) etiology (e.g., post-traumatic), (3) anatomic site of seizure origin (e.g., frontal lobe seizure), (4) tendency to spread to other structures in the brain, and (5) temporal patterns (e.g., nocturnal epilepsy). (From Adams et al., Principles of Neurology, 6th ed, p313)
An anticonvulsant effective in tonic-clonic epilepsy (EPILEPSY, TONIC-CLONIC). It may cause blood dyscrasias.
An autosomal dominant inherited partial epilepsy syndrome with onset between age 3 and 13 years. Seizures are characterized by PARESTHESIA and tonic or clonic activity of the lower face associated with drooling and dysarthria. In most cases, affected children are neurologically and developmentally normal. (From Epilepsia 1998 39;Suppl 4:S32-S41)
A subtype of epilepsy characterized by seizures that are consistently provoked by a certain specific stimulus. Auditory, visual, and somatosensory stimuli as well as the acts of writing, reading, eating, and decision making are examples of events or activities that may induce seizure activity in affected individuals. (From Neurol Clin 1994 Feb;12(1):57-8)
The purpose of this study is to identify patient characteristics (such as baseline seizure frequency) that may predict effective doses of topiramate using just that one drug (monotherapy)...
The purpose of this study is to evaluate the effectiveness and safety of topiramate as add-on therapy in the treatment of epilepsy patrients with Lennox-Gastaut syndrome, a severe form of...
The purpose of this study is to evaluate the effectiveness and safety of topiramate as an add-on therapy in patients with uncontrolled partial onset seizures who are taking one or two stan...
This multi-center, two-treatment study compares the pharmacokinetic profiles of Immediate Release (IR) and Modified Release (MR) formulations of Topiramate (TPM) in patients with epilepsy.
The purpose of this study is to compare the effectiveness and safety of topiramate to standard antiepileptic drugs in children and adults with newly diagnosed epilepsy.
It is well known that oxidative stress plays an important role in the etiology of epilepsy. We investigated effects of selenium (Se) and topiramate (TPM) combination supplementation on antioxidant and...
Topiramate (TPM), a broad-spectrum antiepileptic drug, has been associated with neuropsychological impairment in patients with epilepsy and in healthy volunteers.
Topiramate belongs to a new group of anticonvulsive drugs primarily applied in treatment of epilepsy and in preventive therapy of migraines. Topiramate is structurally unrelated to other antiepileptic...
Purpose. To evaluate the efficacy and tolerability of topiramate (TPM) as monotherapy for patients with temporal lobe epileptic seizures based on an observational study. Methods. We evaluated 41 pati...
A number of experimental and clinical reports suggest the involvement of oxidative stress in pathophysiology of epilepsy. Topiramate, a new antiepileptic drug, induces antioxidant effect in epileptic...