Many patients with neuromyelitis optica spectrum disorder (NMOSD) are managed using off-label immunosuppressants for relapse prevention, and treatment guidelines are based on small, often uncontrolled, studies with low levels of evidence.
To assess real-world treatment patterns in patients with NMOSD.
Based on the global NMOBase cohort, patients diagnosed with NMOSD between 2006–2019 per the international 2015 consensus criteria and with ≥2 Expanded Disability Status Scale scores recorded at different visits were included in the study population. The aquaporin-4 autoantibody (AQP4-IgG) serostatus was determined mainly by cell-based assay; treatment sequence for maintenance therapies was assessed in seropositive (AQP4-IgG+) patients only. The date of biomarker testing was used as a proxy for diagnosis date and served as the baseline for the observational period.
The study population included 334 NMOSD patients tested for AQP4-IgG serostatus. Among them, 301 (90.1%) were AQP4-IgG+. Mean age was 45.3 years; 84.1% were women and 51.8% (n=156) came from Europe. Two thirds had ≥5 visits recorded in NMObase, and the mean observational period was 4.8 years. Five treatment lines (1L–5L) were observed, with only 1.3% of the AQP4-IgG+ cohort (n=4) progressing to the last line. At baseline, the most common therapy was azathioprine (23.6%) followed by rituximab (5.3%), and 65.4% (n=197) were not prescribed any disease-modifying therapy (DMT). The median time between the test date and initiation of DMT was 3.2 months, although 25% of patients waited >10 months. Most AQP4-IgG+ patients (66.4%; n=200) progressed beyond 1L. The most frequent treatments at 2L were rituximab (43.5%) and azathioprine (41.0%). The proportion receiving rituximab, the predominant therapy beyond 2L, remained stable at 3L (48.1%; n=25) and 4L (46.7%; n=7). Across all treatment lines, there were anecdotal reports of use of DMT indicated for multiple sclerosis (MS) (e.g., betaferon), possibly reflecting old clinical practice. A large proportion (83.4%) received corticosteroids, either as acute relapse- or maintenance- therapy, along their treatment pathway.
Based on data collected before recent drug approvals, the main treatment options included off-label drugs and a few MS DMTs. A quarter of patients did not initiate NMOSD DMTs for >10 months from diagnosis. Newly approved therapies might partly address this unmet need, at least for AQP4-IgG+ patients.