The outcome of Guillain-Barré syndrome (GBS) remains unchanged since plasma 
exchange and intravenous immunoglobulin (IVIg) were introduced over 20 years 
ago. Pathogenesis studies on GBS have identified the terminal component of 
complement cascade as a key disease mediator and therapeutic target. We report 
the first use of terminal complement pathway inhibition with eculizumab in 
humans with GBS. In a randomised, double-blind, placebo-controlled trial, 28 
subjects eligible on the basis of GBS disability grade of at least 3 were 
screened, of whom 8 (29%) were randomised. Five received eculizumab for 4 weeks, 
alongside standard IVIg treatment. The safety outcomes, monitored via adverse 
events capture, showed eculizumab to be well-tolerated and safe when 
administered in conjunction with IVIg. Primary and secondary efficacy outcomes 
in the form of GBS disability scores (GBS DS), MRC sum scores, Rasch overall 
disability scores, and overall neuropathy limitation scores are reported 
descriptively. For the primary efficacy outcome at 4 weeks after recruitment, 
two of two placebo- and two of five eculizumab-treated subjects had improved by 
one or more grades on the GBS DS. Although the small sample size precludes a 
statistically meaningful analysis, these pilot data indicate further studies on 
complement inhibition in GBS are warranted.