To evaluate the efficacy and safety of inebilizumab(INEB) in AQP4+ NMOSD participants who self-identified as Asian, Hispanic/Latino(H/L), and Black/African American(B/AA) in the N-MOmentum study.

N-MOmentum(NCT02200770) was a double-blind, phase 2/3 trial that assessed the efficacy and safety of INEB in adults with NMOSD, with a 28-week randomized controlled period(RCP) (intravenous INEB 300mg or placebo[PBO] on days 1 and 15) and an open-label period(OLP) of ≥2 years.  Post hoc analyses were conducted for AQP4+ participants who self-identified as Asian, H/L, B/AA.

Of 230 participants in N-MOmentum, race/ethnic self-identification included Asian(n=47), H/L(n=43), B/AA(n=20), and White(n=120). Participants receiving INEB in the RCP were less likely to have an attack compared to PBO(Hazard Ratio[95%CI],p-value): Asian 0.20[0.06, 0.66],p=0.01; H/L 0.25[0.06, 1.01],p=0.05; B/AA 0.33[0.02, 5.31],p=0.44; White 0.27[0.11, 0.66],p=0.004. Expanded Disability Status Scale(EDSS) score worsening from baseline to last RCP visit for participants receiving INEB vs PBO (Odds Ratio[95%CI],p-value): Asian 0.58[0.09, 3.63],p=0.56; H/L 0.50[0.09, 2.70],p=0.4; White 0.37[0.14, 0.95], p=0.04; and B/AA participants receiving INEB (0/15) did not experience EDSS worsening compared to 20% of PBO (1/5) participants. In the 225 participants who received any INEB during the study (combined RCP and OLP), the annualized attack rate [95% CI] was: Asian (n=46) 0.10[0.05, 0.18]; H/L (n=40) 0.07[0.04, 0.15]; B/AA (n=19) 0.05[0.01, 0.33]; White (n=120) 0.08[0.05, 0.13]. Among any INEB participants, ≥1 investigational product-related treatment-emergent adverse event (IP-TEAE) was reported: Asian 34.8%(16/46); H/L 30.0%(12/40); B/AA 63.2%(12/19); White 40.0%(48/120).

Non-White NMOSD participants receiving inebilizumab had improved outcomes when compared to placebo and were similar to White participants although evaluation of larger populations is needed to confirm these results.