First North American Regional Epilepsy Congress: Add-on Pregabalin for Refractory Epilepsy
Speaker: Iratxe Maestro, MD, Neurologist, Department of Neurology, Hospital Clinic, Barcelona, Spain (Drug Lyrica, Pfizer), an antiepileptic drug, has proved effective and well tolerated when used in everyday clinical practice as adjunctive therapy in patients with refractory epilepsy. This agent was introduced in Europe in February 2005. It acts as a ligand for the alpha2-delta subunit associated with voltage-gated calcium channels.
A study was conducted to assess the efficacy and tolerabil-ity of pregabalin as add-on treatment for refractory seizures. A total of 101 patients with persistent seizures at two tertiary hospitals in Spain were retrospectively evaluated from February 2005 to May 2006. They had already been treated with one to three antiepileptic agents. Their charts were reviewed, their type of epilepsy was analyzed, and the number of concomitant antiepileptic drugs was determined. Seizure frequency before and after pregabalin treatment was established. Adverse effects, as well as continuation or discontinuation of pregabalin therapy, were noted.
Forty-three of the 101 patients had temporal lobe epilepsy, followed by frontal lobe epilepsy (29 patients), nonlocalized focal epilepsy (23 patients), parieto-occipital epilepsy (four patients), and multifocal epilepsy (two patients). The mean number of concomitant agents used was 2.8. Seizures were highly refractory to treatment, and patients had an average of 48.5 seizures per month. The mean follow-up period was eight months. discount drugs canda
Overall, 53 patients (52%) responded to pregabalin and experienced at least a 50% reduction in seizures. Fourteen patients (14%) became seizure-free for at least two months and remained free of seizures during the study. Four patients experienced a temporary increase in seizure frequency related to the drug. Three patients reported a similar number of seizures but of less severity.
Pregabalin was generally well tolerated, with at least one adverse effect reported in 60% of the treated patients. Weight gain of more than 10% was the most common side effect in 23 patients, and dizziness with or without ataxia was observed in 14 patients. The dizziness usually resolved after the dose of concomitant antiepileptic drugs was reduced by 30% to 50%; there was no need to lower the total daily dose of pregabalin.
Overall, 78.2% of the patients continued receiving pregabalin during the study. The remaining 21.7% of patients stopped taking pregabalin because of adverse effects (nine patients), lack of efficacy (six patients), or both (seven patients).
Prescribing physicians were asked to rate their patients in terms of the drug’s efficacy and tolerability. Eighteen patients (17.8%) were rated as “highly improved,” 42 patients (41.5%) as “improved,” 31 patients (30.6%) as “unchanged,” six patients (5.9%) as “worse,” and four patients (3.9%) as “much worse.”
Vigabatrin Valuable in Infantile Spasms of Multiple Etiology
Speaker: Roy D. Elterman, MD, Specialist in Pediatric Epilepsy, Dallas Pediatric Neurology Associates, and Clinical Professor of Neurology, University of Texas Southwestern Medical School, Dallas, Texas
Vigabatrin (Sabril, Ovation), a novel antiepileptic drug that inhibits catabolism of gamma-aminobutyric acid (GABA), rapidly produces freedom from spasms.
Initially, the Vigabatrin Infantile Spasms Study Group had demonstrated that vigabatrin produced seizure cessation in patients with infantile spasms, particularly spasms resulting from tuberous sclerosis. These spasms are a catastrophic form of childhood epilepsy, with an onset during the first few months of life.
The original study was a multicenter, randomized, single-blind trial with up to a three-year, open-label, flexible-dosing follow-up period. The study group selected 221 patients from the intent-to-treat cohort to receive high-dose vigabatrin (100-148 mg/kg per day) or low-dose vigabatrin (18-36 mg/kg per day) for 14 to 21 days.
The dose was administered orally twice daily. An a priori analysis was conducted on the data of the original study to evaluate the efficacy of vigabatrin according to the etiology of infantile spasm.
The median time to the onset of cessation of spasms for all patients ranged from three to 14 weeks and began within one week for patients with tuberous sclerosis. Response rates for patients receiving the high dose of vigabatrin were greater than for patients receiving the low dose. These rates were maintained throughout the study period for all causes of spasm.
Of particular interest were the response rates for spasm cessation for seven consecutive days and in patients remaining spasm-free for the duration of the study (up to three years). Response rates were 73.7% for tuberous sclerosis, 71.9% for cryptogenic infantile spasms, and 49.6% for “symptomatic-other” infantile spasms. The percentage of patients who became spasm-free for seven consecutive days during the study period and who avoided relapse differed significantly for each patient group. Patients with tuberous sclerosis achieved the highest spasm-free status (97.4%), followed by patients with a cryptogenic cause (84.2%) and symptomatic-other etiology (68.2°%). online pharmacy uk
In summary, the data suggest that vigabatrin should be considered as a first-line therapy for all causes of infantile spasms.