Dubey D, Britton J, McKeon A, et al. - In this first randomized double-blind placebo-controlled trial involving 17 patients (12 men, 5 women), researchers tested the effectiveness of intravenous immunoglobulin (IVIG) in decreasing seizure frequency. The sample consisted of 30 leucine-rich, glioma-inactivated 1 (LGI1)/contactin-associated protein-like 2 (CASPR2)-IgG–seropositive adult patients with ≥ 2 seizures per week. Study participants were randomized to receive IVIG (0.5 g/kg day 1, 1 g/kg day 2, 0.6 g/kg weeks 3 and 5) or volume-matched intravenous normal saline. The study was stopped due to slow recruitment after enrollment of individuals (LGI1-IgG, 14; CASPR2-IgG, 3) over 34 months. For all patients and the subset of LGI1-IgG, IVIG's superiority over placebo exceeded statistical significance for the primary endpoint. Such findings must be viewed with the caveat that the analysis has not achieved its sample size which was originally selected.