Clinical Trials Poster Presentation

P0189 - AQP4-IgG seronegative patient outcomes in the N-MOmentum trial of inebilizumab in neuromyelitis optica spectrum disorder (ID 1288)

  • R. Marignier
  • S. Pittock
  • F. Paul
  • R. Marignier
  • H. Kim
  • J. Bennett
  • B. Weinshenker
  • D. Wingerchuk
  • A. Green
  • K. Fujihara
  • G. Cutter
  • O. Aktas
  • H. Hartung
  • J. Drappa
  • J. Ratchford
  • D. She
  • D. Cimbora
  • E. Katz
  • B. Cree
Presentation Number
Presentation Topic
Clinical Trials



The N-MOmentum trial of inebilizumab included patients with aquaporin 4-IgG seropositive (AQP4+) or seronegative (AQP4−) neuromyelitis optica spectrum disorder (NMOSD).


To report AQP4− participant outcomes in N-MOmentum. .......................................................


Medical histories and screening data for AQP4− patients were assessed independently by 3 clinical experts before enrollment. Majority decision confirmed diagnoses using the 2006 criteria. Myelin oligodendrocyte glycoprotein-IgG (MOG) serology and annualized attack rates (AARs) were tested post hoc. These observations do not account for bias in estimates of effects on the AAR caused by regression to the mean, introduced by inclusion criteria requiring attacks during the 1 to 2 years before study entry.


Only 18/50 AQP4− patients (36%) were eligible for randomization; 17 were randomized, 4 to placebo (1 MOG+) and 13 to inebilizumab (6 MOG+). Reasons for not enrolling prospective AQP4− NMOSD participants were mainly related to lack of fulfillment of MRI findings required by the 2006 criteria.

Owing to limited patient numbers, we compared the on-study to the pre-study AAR for treated participants to assess treatment effects.

For AQP4− participants (n=17), 40 attacks occurred in 23 patient-years of pre-study follow-up with mean AAR (95% confidence interval) of 1.72 (1.23–2.33). For MOG+ participants (n=7), 16 attacks occurred in 8.3 patient-years of pre-study follow-up with an AAR of 1.93 (1.11–3.14). For double-seronegative participants (n=10), 24 attacks occurred in 15 patient-years of pre-study follow-up with an AAR of 1.60 (1.02–2.38).

After receiving inebilizumab, AARs declined in all groups by the end of the randomized controlled period: AQP4− participants (n=13), 0.09 (0.02–0.26), or 3 attacks in 34.2 patient-years; MOG+ participants (n=6), 0.08 (0.002–0.464), or 1 attack in 12 patient-years; double-seronegative participants (n=7), 0.09 (0.011–0.326), or 2 attacks in 22 patient-years.

The benefit was sustained with longer-term inebilizumab exposure. At 120 days into the open-label period (OLP), during which all participants received inebilizumab, the AAR in AQP4− participants (n=17) remained low (0.069 [0.014–0.202]). No attacks were seen in any AQP4−, MOG+ or double seronegative patient during the OLP.


The N-MOmentum trial provides clinically important insight on the difficulty of correctly diagnosing AQP4− NMOSD and suggests that inebilizumab may have a benefit on AAR in these patients.