Clinical and immunomodulatory profiles of satralizumab and rituximab in AQP4-IgG+ NMOSD: A retrospective cohort study

Abstract

Background & Objective: Seropositive neuromyelitis optica spectrum disorder (NMOSD) is characterized by frequent relapses and substantial disability rates. The efficacy and safety of existing drugs vary. There are relatively few direct comparative studies of satralizumab and rituximab. The objective of this study is to systematically compare the efficacy and immunomodulatory effects of satralizumab and rituximab in patients with NMOSD.

Methods: A retrospective controlled study design was adopted to select 132 NMOSD patients hospitalized at The Second Hospital of Lanzhou University spanning January 2019 to December 2023. After exclusion, 129 cases were included, 3 cases were lost to follow-up, and 4 cases were excluded due to incomplete data. Finally, a total of 122 cases were analyzed and divided into Group A (rituximab treatment, 60 cases) and Group B (satralizumab treatment, 62 cases) according to the treatment plan. The primary observation indicators included Annualized Relapse Rate (ARR), recurrence time, changes in Expanded Disability Status Scale (EDSS) score, changes in AQP4-IgG concentration, Treg and CD20+ cell counts, and the secondary observation indicators included levels of inflammatory factors (IL-6, TNF-α), levels of IgG subclasses (IgG1, IgG3), incidence of adverse events, and quality of life score (SF-36).

Results: Baseline data between the two patient groups were numerically indistinguishable, with the groups being comparable (P>0.05). After treatment, Group B had higher AQP4-IgG concentration, Treg cell count, CD20+ cell count, IgG1, IgG3, and SF-36-GH score than Group A (95%CI: -0.19--0.005, P=0.038; 95%CI: -8.77-- 1.17, P=0.011; 95%CI: -242.42--237.89, P<0.001; 95%CI: -5.00--0.94, P=0.004; 95%CI: -3.80--0.02, P=0.048; 95%CI: -7.98--0.04, P=0.048); and Group B had numerically lower ARR, EDSS score, IL-6, and TNF-α than Group A (95%CI: 0.003-0.09, P=0.035; 95%CI: 0.004-0.7, P=0.047; 95%CI: 0.39- 1.66, P=0.002; 95%CI: 0.13-6.91, P=0.042). Group B had fewer adverse events were observed in the incidence of infusion/injection reactions and infection (95%CI: 1.10-25.63, P=0.023; 95%CI: 0.94- 22.71, P=0.042). The recurrence time in Group B was longer than that in Group A [HR: 1.77 (1.16, 2.72), P=0.006]

Conclusion: In this single-center retrospective cohort of AQP4-IgG+ NMOSD, satralizumab use was associated with lower ARR and EDSS at 18 months than those treated with rituximab, whereas rituximab was associated with greater peripheral CD20+ B-cell depletion. These are unadjusted observational associations and should be interpreted cautiously; prospective randomized studies are needed to confirm comparative effectiveness and safety.