Inebilizumab: A Review in Neuromyelitis Optica Spectrum Disorder

Inebilizumab (Uplizna(R)) is a recently approved monoclonal antibody for use in adults with neuromyelitis optica spectrum disorder (NMOSD) who are anti-aquaporin-4 (AQP4) antibody seropositive. Inebilizumab targets the B cell antigen CD19 and effectively depletes circulating B cells, thus suppressing inflammatory NMOSD attacks that are potentially disabling or life-threatening. It is approved as an intravenous infusion in several countries. In the pivotal phase 2/3 N-MOmentum trial, inebilizumab reduced the risk of NMOSD attacks compared with placebo, including in AQP4-antibody seropositive patients. Inebilizumab also significantly reduced the risk of disability score worsening, the number of NMOSD-related hospitalisations and MRI lesion count, but had no significant effect on low-contrast binocular vision. The treatment effect on relapse risk and disability scores was sustained in inebilizumab-treated patients for >= 4 years during the open-label extension. Inebilizumab was generally well tolerated, with the most common adverse events being urinary tract infection and arthralgia. Thus, inebilizumab is an effective treatment option for adults with AQP4-antibody seropositive NMOSD. Plain Language Summary Neuromyelitis optica spectrum disorder (NMOSD) is a chronic condition denoted by relapsing autoimmune attacks affecting the central nervous system, which may lead to accruing disability or death. It is frequently associated with anti-aquaporin-4 (AQP4) autoantibodies. In recent years, three new monoclonal antibody therapies have gained regulatory approval for the treatment of NMOSD. Inebilizumab (Uplizna (R)), a monoclonal antibody that targets B cells, is approved for use in AQP4-antibody seropositive adults as an intravenous infusion. Inebilizumab was effective at preventing NMOSD relapse compared with placebo in a pivotal phase 2/3 trial. It also prevented worsening of disability scores, and decreased the number of NMOSD-related hospitalisations and MRI lesions, but did not significantly improve low-contrast binocular vision. The clinical benefit of inebilizumab was maintained long-term (>= 4 years in the open-label extension). Inebilizumab was generally well tolerated, with most adverse events being mild to moderate in severity. The most common adverse events were urinary tract infection and joint pain. Inebilizumab provides an effective option for preventing NMOSD attacks in adults who are AQP4-antibody seropositive.