For an adult, rituximab is effective as long-term maintenance therapy to reduce NMOSD relapses, although its use for NMOSD is off-label.
In an 86-patient randomized trial, rituximab significantly reduced the annualized relapse rate compared with azathioprine.
In a 38-patient randomized trial of AQP4-IgG–positive NMOSD, relapse occurred in 0% with rituximab versus 37% with placebo over a median 72 weeks. The small trial size limits certainty.
Observational studies also associate treatment with fewer relapses and less neurologic disability.
For AQP4-IgG–positive NMOSD, long-term relapse-prevention immunotherapy is recommended and includes rituximab as an option. However, where available, therapies supported by larger randomized trials and specifically approved for AQP4-IgG–positive NMOSD are generally preferred. For seronegative NMOSD, long-term immunotherapy including rituximab is suggested, but the evidence is less certain.