Inebilizumab Meets Primary and Secondary Endpoints for Treatment of Neuromyelitis Optica Spectrum Disorder
In a global trial of inebilizumab (Viela Bio, Gaithersberg, MD) for the treatment of patients with neuromyelitis optica spectrum disorder (NMOSD), the drug met its primary and secondary endpoints. The trial showed that treatment with inebilizumab resulted in a 77% reduction in the risk of developing an NMOSD attack in patients compared to treatment with placebo. Secondary analysis showed a reduction in disability worsening in patients treated with inebilizumab compared with those treated with placebo.
“These results support our hypothesis that CD19 expressing B cells including plasmablasts and plasma cells play a key role in the pathogenesis of NMOSD,” said Jorn Drappa, MD, PhD, chief medical officer and head of research and development at Viela Bio. “This study demonstrated a highly significant and clinically meaningful reduction in attack risk and suggests a promising new treatment for patients diagnosed with NMOSD.”
Inebilizumab is a humanized monoclonal antibody that binds with high affinity to CD19, a protein expressed on a broad range of B cells, including antibody-secreting plasmablasts and plasma cells. After inebilizumab binding to CD19, B cells are rapidly depleted from the body.
NMOSD is a proposed unifying term for neuromyelitis optica (NMO)—also known as Devic's disease—and related demyelinating syndromes that are distinct from multiple sclerosis. Distinguishing NMOSD from MS and finding proven treatments to prevent relapses of NMOSD is critical because some drugs (eg, interferon-ß, natalizumab, or fingolimod) used to treat MS are ineffective or make NMOSD worse. All treatments in current use to prevent NMOSD relapses (eg, azathioprine, rituximab, or mycophenolate mofetil) are used off-label based upon open-label prospective or retrospective studies and clinician experience.
In the N-MOmentum (NCT02200770) trial 231 patients with NMOSD were randomly assigned to receive 2 intravenous doses of inebilizumab monotherapy or placebo, and followed for 6.5 months. They were subsequently placed into open-label extension in which they received inebilizumab every 6 months.