Treatment of refractory epilepsy with intravenous immunoglobulins

Summary

Sixty-one refractory epileptic patients (46 with partial epilepsy) were treated with intravenous immunoglobulins in a controlled double-blind/dose finding clinical trial; 18 (7 females, mean age 18.5 years) received placebo, while 14 (3 females, mean age 26.2 years, 2 excluded), 14 (4 females, mean age 24.6 years, 1 excluded) and 15 (5 females, mean age 24.4 years) patients received 100, 250 and 400 mg/kg per infusion of intravenous immunoglobulins, respectively. Seven perfusions were scheduled, four the 1st week, and thereafter one during the 2nd, 3rd and 6th week. The patients were followed for 6 months. An optional infusion was given at the end of the study. A comparison of the mean number of seizures per day was made between the baseline (4 weeks before the first infusion) and the 6th month after the first infusion. Patients were considered responders if they had a decrease of at least 50% in daily seizure frequency at the end of the study compared with the baseline. We did not find severe adverse events. One patient had to stop infusions for possible related side effects (vomiting). When all patients were analyzed together, we found a positive trend in favor of intravenous immunoglobulin treatment, but this was not significant (P=0.095). There was no relationship between dose and efficacy (P=0.31). When the largest group with partial epilepsy was analyzed separately, we noted 19 responders in the test group, compared with 2 in the placebo. These results were significant (P=0.041) and remained significant in the subgroup of partial epilepsy with secondarily generalized seizures (30 patients,P=0.049). The results were not significant after the 3rd month. There was an insignificant correlation between a better therapeutic response and a lower IgA serum level (P=0.07) or a more severe daily seizure frequency (P=0.06). The mechanisms of action of intravenous immunoglobulins in epilepsy still remain hypothetical.