Bennett, Jeffrey L.

Background: The N-MOmentum trial investigated safety and efficacy of inebilizumab in participants with neuromyelitis optica spectrum disorder (NMOSD). Objective: Evaluate the attack identification process and adjudication committee (AC) performance in N-MOmentum. Methods: Adults ( n = 230) with NMOSD and Expanded Disability Status Scale score ⩽8 were randomized (3:1) to inebilizumab 300 mg or placebo. The randomized controlled period was 28 weeks or until adjudicated attack. Attacks were adjudicated according to 18 predefined criteria. Magnetic resonance imaging (MRI) and biomarker (serum glial fibrillary acidic protein [sGFAP]) analyses were performed. Results: A total of 64 participant-reported neurological events occurred; 51 (80%) were investigator-determined to be attacks. The AC confirmed 43 of the investigator-determined attacks (84%). There was high inter- and intra-AC-member agreement. In 25/64 events (39%) and 14/43 AC-adjudicated attacks (33%), MRI was reviewed during adjudication. Retrospective analysis revealed new domain-specific T1 and T2 MRI lesions in 90% of adjudicated attacks. Increased mean sGFAP concentrations (>2-fold change) from baseline were observed in 56% of adjudicated attacks versus 14% of investigator-determined attacks rejected by the AC and 31% of participant-reported events determined not to be attacks. Conclusion: AC adjudication of NMOSD attacks according to predefined criteria appears robust. MRI lesion correlates and sGFAP elevations were found in most adjudicated attacks.

Abstract Background and Objectives: Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein not previously described in the central nervous system (CNS). We aimed to determine MFAP4 CNS expression and measure cerebrospinal fluid (CSF) and serum levels. Methods: Tissue was sampled at autopsy from patients with acute multiple sclerosis (MS) (n=3), progressive MS (n=3), neuromyelitis optica spectrum disorder (NMOSD) (n=2), controls (n=9), including 6 healthy controls (HC). MFAP4 levels were measured in 152 patients (49 MS, 62 NMOSD, 22 myelin oligodendrocyte glycoprotein associated disease (MOGAD), and 19 isolated optic neuritis (ION). Results: MFAP4 localized to the meninges and the vascular/perivascular spaces, particularly intense in the optic nerve. At sites of active inflammation, MFAP4 reactivity was reduced in NMOSD and acute MS and to a lesser degree in progressive MS. CSF MFAP4 levels were reduced in patients during acute attacks compared to HC. There was a positive correlation between number of relapses and CSF MFAP4 levels (rho=0.33, p=0.004). CSF MFAP4 levels were lower in 53 samples obtained at presenting attack (mean U/mL: 14.3, MOGAD 9.7 and ION 14.6 relative to HC 17.9. (p=0.013, p=0.000 and p=0.019 respectively). All patients with acute ON relapse (n=68) had reduced CSF MFAP4 relative to HC (mean U/mL: 14.5 vs. 17.9, p=0.006). CSF MFAP4 levels correlated negatively with relapse severity (rho=-0.41, p=0.017). Discussion.: MFAP4 immunoreactivity was observed in CNS and reduced at sites of active inflammation. CSF levels of MFAP4 were reduced following acute relapse and may serve as a marker of disease activity and attack severity.

Objective CHAMPION‐NMOSD (NCT04201262) is a phase 3, open‐label, externally controlled interventional study evaluating the efficacy and safety of the terminal complement inhibitor ravulizumab in adult patients with anti–aquaporin‐4 antibody–positive (AQP4+) neuromyelitis optica spectrum disorder (NMOSD). Ravulizumab binds the same complement component 5 epitope as the approved therapeutic eculizumab but has a longer half‐life, enabling an extended dosing interval (8 vs 2 weeks). Methods The availability of eculizumab precluded the use of a concurrent placebo control in CHAMPION‐NMOSD; consequently, the placebo group of the eculizumab phase 3 trial PREVENT (n = 47) was used as an external comparator. Patients received weight‐based intravenous ravulizumab on day 1 and maintenance doses on day 15, then once every 8 weeks. The primary endpoint was time to first adjudicated on‐trial relapse. Results The primary endpoint was met; no patients taking ravulizumab (n = 58) had an adjudicated relapse (during 84.0 patient‐years of treatment) versus 20 patients with adjudicated relapses in the placebo group of PREVENT (during 46.9 patient‐years; relapse risk reduction = 98.6%, 95% confidence interval = 89.7%–100.0%, p < 0.0001). Median (range) study period follow‐up time was 73.5 (11.0–117.7) weeks for ravulizumab. Most treatment‐emergent adverse events were mild/moderate; no deaths were reported. Two patients taking ravulizumab experienced meningococcal infections. Both recovered with no sequelae; one continued ravulizumab treatment. Interpretation Ravulizumab significantly reduced relapse risk in patients with AQP4+ NMOSD, with a safety profile consistent with those of eculizumab and ravulizumab across all approved indications. ANN NEUROL 2023;93:1053–1068

Background: In the N-MOmentum trial, the risk of an adjudicated neuromyelitis optica spectrum disorder (NMOSD) attack was significantly reduced with inebilizumab compared with placebo. Objective: To demonstrate the robustness of this finding, using pre-specified sensitivity and subgroup analyses. Methods: N-MOmentum is a prospective, randomized, placebo-controlled, double-masked trial of inebilizumab, an anti-CD19 monoclonal B-cell-depleting antibody, in patients with NMOSD. Pre-planned and post hoc analyses were performed to evaluate the primary endpoint across a range of attack definitions and demographic groups, as well as key secondary endpoints. Results: In the N-MOmentum trial (ClinicalTrials.gov: NCT02200770), 174 participants received inebilizumab and 56 received placebo. Attack risk for inebilizumab versus placebo was consistently and significantly reduced, regardless of attack definition, type of attack, baseline disability, ethnicity, treatment history, or disease course (all with hazard ratios < 0.4 favoring inebilizumab, p < 0.05). Analyses of secondary endpoints showed similar trends. Conclusion: N-MOmentum demonstrated that inebilizumab provides a robust reduction in the risk of NMOSD attacks regardless of attack evaluation method, attack type, patient demographics, or previous therapy. The N-MOmentum study is registered at ClinicalTrials.gov: NCT2200770.