Open, double-blind and long-term study of vigabatrin in chronic epilepsy.
We performed an open, double-blind, and long-term study of vigabatrin (gamma-vinyl-GABA, GVG) in patients with treatment-resistant epilepsy who were receiving only one or at most two standard antiepileptic drugs (AEDs). The novel design included a parallel, double-blind, placebo-controlled phase that minimized the number of patients receiving placebo and allowed determination of the optimum dose of GVG for each patient before initiation of the double-blind phase. The study was divided into four phases. The first phase was a 6-week period of baseline observation. In the second phase, GVG was added openly to previous AEDs for 8 weeks. During the first 2 weeks of this phase, the dose of GVG was increased weekly and then, in the absence of adverse effects, was held constant for the next 6 weeks. At the end of this open phase, seizure frequency during the 6 weeks of constant treatment was compared with the baseline seizure frequency for each patient. Patients who experienced reduction greater than 50% in the frequency of any seizure type during the open phase were defined as responders. These responders were then entered into the third and double-blind phase, in which they were randomly allocated wither to continue active GVG treatment or placebo for 8 weeks. Thirty-three patients entered the study; 31 of 33 patients completed the initial open phase. Twenty patients achieved a reduction greater than or equal to 50% in the frequency of one or more seizure types and were eligible for the double-blind phase; 10 were randomized to continue GVG and 10 were randomized to placebo.(ABSTRACT TRUNCATED AT 250 WORDS)
Reynolds
E H
EH
Maudsley Hospital, London, England.
Ring
H A
HA
Farr
I N
IN
Heller
A J
AJ
Elwes
R D
RD
D000293:Adolescent; D000328:Adult; D000368:Aged; D000614:Aminocaproates / Q000009:adverse effects / Q000627:therapeutic use*; D000927:Anticonvulsants / Q000009:adverse effects / Q000627:therapeutic use*; D002908:Chronic Disease; D003863:Depression / Q000139:chemically induced; D004311:Double-Blind Method; D004827:Epilepsy / Q000188:drug therapy*; D004833:Epilepsy, Temporal Lobe / Q000188:drug therapy; D005260:Female; D006261:Headache / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos; D012894:Sleep Stages; D020888:Vigabatrin
D000614:Aminocaproates; D000927:Anticonvulsants; D010919:Placebos; D020888:Vigabatrin