Phase 2b Randomized Trial of Inebilizumab for Anti-NMDA Receptor Encephalitis Assessing Safety and Disease Markers

What this Trial Is About

Researchers are evaluating the effects of inebilizumab, a monoclonal antibody targeting B-cells, on patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, a serious autoimmune brain condition. The trial aims to compare standard "first-line" immunotherapy alone versus combined with inebilizumab or placebo, focusing on changes in disability measured by the modified Rankin score at 16 weeks. This Phase 2b randomized controlled trial also studies safety and seeks to identify biological markers that predict treatment response and long-term outcomes. Participants will be randomly assigned to receive either inebilizumab or a placebo, both given intravenously on Day 1 and Day 15, alongside standard first-line treatments including high-dose corticosteroids and intravenous immunoglobulin (IVIg). Rescue therapy with cyclophosphamide may be offered after week 6 if needed. All participants receive a 3-day IVIg course as part of their initial treatment. The trial includes a quadruple-blind design and plans to enroll about 116 participants aged 12 years and older with moderate-to-severe NMDAR encephalitis. During the study, participants will attend scheduled visits to assess neurological function using the modified Rankin scale and other cognitive and quality of life tests up to 96 weeks. Researchers will monitor safety by tracking adverse events and measure immune markers including NMDAR autoantibody levels. The trial will also use neuropsychological assessments and cognitive screening tools to evaluate patient outcomes and understand the biology behind treatment effects. Participants must be willing and able to complete study visits and assessments throughout the trial period.

The ExTINGUISH Trial of Inebilizumab in NMDAR Encephalitis