Methods of assessment of antiepileptic drugs.

Abstract

Epilepsy is a symptom with protean manifestations and as such it is a difficult disease in which to carry out a therapeutic trial. The methods available to research workers for the assessment of new antiepileptic drugs are hampered by the fact that epilepsy is a fluctuant condition. Although it is a chronic disorder open to study using cross‐over trials and within‐patient comparisons, accurate assessment cannot be easily made at any one point in time. Research workers are therefore automatically placed at a time factor disadvantage and this is especially so for those searching for quick methods of evaluating new compounds. The need for a quick and reliable method of assessing a new antiepileptic drug has long been appreciated. This article will discuss the methods currently available and we will begin by considering the most commonly used method of assessment with particular reference to some of the problems involved in conducting a controlled clinical trial in epilepsy.

Lamotrigine

“…[36] Eight of 17 paediatric patients with refractory and frequent absence seizures had a ≥80% reduction from baseline in spike-and-wave episodes when treated with lamotrigine for 12 to 48 weeks (no dosage reported). [36] Eight of 17 paediatric patients with refractory and frequent absence seizures had a ≥80% reduction from baseline in spike-and-wave episodes when treated with lamotrigine for 12 to 48 weeks (no dosage reported).…”

“…[36,37] The earliest and simplest manifestation of epileptiform activity on the EEG is interictal spike discharge; [37] there is general agreement that reduction in these discharges should parallel improvement in seizure control. [36,37] The earliest and simplest manifestation of epileptiform activity on the EEG is interictal spike discharge; [37] there is general agreement that reduction in these discharges should parallel improvement in seizure control.…”

Acute Effects of Lamotrigine (BW430C) in Persons With Epilepsy

“…Changes in vigilance may present particular problems in acute drug studies, because anxiety provoked by administration of the experimental agent, boredom due to prolonged EEG recording, or drowsiness induced by the AED itself may all affect the discharge rates. Nevertheless, interictal spike counting has successfully been used for acute studies of AED-action, for instance by Milligan and colleagues (Milligan and Richens, 1981;Milligan et al, 1982;Milligan et al, 1983). The photoconvulsive response (PCR) is amenable to quantification by measurement of the photosensitivity range (Jeavons and Harding, 1975) and shows a high level of consistency when assessed in a standardized manner at hourly intervals over the course of a waking day .…”

Pattern‐Reversal VEP and Cortical SEP Latency Prolongations in Epilepsy

“…The present knowledge of evoked potentials in epilepsy is largely based on VEP studies, the results of which are not uniform. The discrepancies are partly due to differences in technique, terminology, and patient populations (Millican and Richens, 1981), as well as to the probable effects of anticonvulsant drugs and the nature of the underlying pathology.…”