This is a nationwide observational study looking at how ravulizumab, a complement C5 inhibitor, affects blood biomarkers o sNfL and sGFAP in people with AQP4-antibody positive NMOSD. The study does not change your treatment-only regular blood samples are collected to monitor these markers
Patient must be 18 years of age or older, at the time of signing the informed consent.
Anti-AQP4 Ab-positive at screening and a diagnosis of NMOSD as defined by the 2015 international consensus diagnostic criteria (Wingerchuk, 2015). A historically positive anti-AQP4 Ab test may be acceptable if the test was performed using an acceptable, validated cell-based assay from an accredited laboratory.
At least 1 clinical attack prior to the Prescreening/Screening Periods.
Treatment-naïve patients or patients under specific off-label treatments (rituximab, corticosteroids, azathioprine, mycophenolate mofetil) or the complement C5 inhibitor ravulizumab. Naïve patients who initiate ravulizumab at enrolment, should have been prescribed ravulizumab, but not yet initiated treatment, according to the label and local market reimbursement criteria.
History of N. meningitidis infection.
Human immunodeficiency virus (HIV) infection (evidenced by HIV-1 or HIV-2 antibody titer)
History of unexplained infections.
Active systemic bacterial, viral, or fungal infection within 14 days prior to screening.