Intravenous immunoglobulins for epilepsy

Background: Epilepsy is a common neurological condition, with an estimated incidence of 50 per 100,000 persons. People with epilepsy may present with various types of immunological abnormalities, such as low serum immunoglobulin A (IgA) levels, lack of the immunoglobulin G (IgG) subclass and identification of certain types of antibodies. Intravenous immunoglobulin (IVIg) treatment may represent a valuable approach and its efficacy has important implications for epilepsy management. This is an update of a Cochrane review first published in 2011 and last updated in 2017.

Objectives: To examine the effects of IVIg on the frequency and duration of seizures, quality of life and adverse effects when used as monotherapy or as add-on treatment for people with epilepsy.

Search methods: For the latest update, we searched the Cochrane Register of Studies (CRS Web) (20 December 2018), MEDLINE (Ovid, 1946 to 20 December 2018), Web of Science (1898 to 20 December 2018), ISRCTN registry (20 December 2018), WHO International Clinical Trials Registry Platform (ICTRP, 20 December 2018), the US National Institutes of Health ClinicalTrials.gov (20 December 2018), and reference lists of articles.

Selection criteria: Randomised or quasi-randomised controlled trials of IVIg as monotherapy or add-on treatment in people with epilepsy.

Data collection and analysis: Two review authors independently assessed the trials for inclusion and extracted data. We contacted study authors for additional information. Outcomes included percentage of people rendered seizure-free, 50% or greater reduction in seizure frequency, adverse effects, treatment withdrawal and quality of life.

Main results: We included one study (61 participants). The included study was a randomised, double-blind, placebo-controlled, multicentre trial which compared the treatment efficacy of IVIg as an add-on with a placebo add-on in patients with drug-resistant epilepsy. Seizure freedom was not reported in the study. There was no significant difference between IVIg and placebo in 50% or greater reduction in seizure frequency (RR 1.89, 95% CI 0.85 to 4.21; one study, 58 participants; low-certainty evidence). The study reported a statistically significant effect for global assessment in favour of IVIg (RR 3.29, 95% CI 1.13 to 9.57; one study, 60 participants; low-certainty evidence). No adverse effects were demonstrated. We found no randomised controlled trials that investigated the effects of IVIg monotherapy for epilepsy. Overall, the included study was rated at low to unclear risk of bias. Using GRADE methodology, the certainty of the evidence was rated as low.

Authors' conclusions: We cannot draw any reliable conclusions regarding the efficacy of IVIg as a treatment for epilepsy. Further randomised controlled trials are needed.