Ravulizumab, a newer humanized mAb against C5 with less frequent infusion regimen compared to eculizumab is being evaluated for efficacy and safety in a Phase 3, placebo-controlled, open-label, multicenter study in adult patients with anti-AQP-4 (+) neuromyelitis optica spectrum disorder (NMOSD) [136]. Here, AQP4 is linked to neuromyelitis optica.