AQP4 and neuromyelitis optica: In this trial, patients with AQP4-positive or AQP4-negative NMO-SD, and an EDSS score of 6.5 or less, were randomly assigned (2:1) treatment with satralizumab (subcutaneous, every 2-weeks for 4 weeks and every 4-weeks thereafter; n = 63) or placebo (matched administration; n = 32).