Objective:

To investigate the efficacy and safety of Inebilizumab in treating Neuromyelitis Optica Spectrum Disorder (NMOSD) patients with Aquaporin-4-Immunoglobulin G (AQP4-IgG) and have comorbid autoimmune diseases.

Background:

In NMOSD patients, 20%-30% have comorbid autoimmune diseases characterized by antibody-mediated B-cell hyperactivity. Inebilizumab, a humanized anti-CD19 monoclonal antibody, depletes B cells and reduces relapse and disability in NMOSD. Its efficacy in patients with autoimmune comorbidities, however, remains uncertain.

Design/Methods:

We conducted a multicenter retrospective cohort study including NMOSD patients with autoimmune comorbidities who received at least two doses of inebilizumab. Clinical outcomes included relapse occurrence, Expanded Disability Status Scale (EDSS) scores, improvement in comorbid disease symptoms, and changes in disease activity. Treatment safety was also evaluated.

Results:

Twenty-nine female patients (median age, 43.4 years) were treated with inebilizumab for a median of 1.3 years. Comorbidities included Sjögren’s syndrome (SS, n=9), undifferentiated connective tissue disease (n=8), hypothyroidism (n=8), Hashimoto’s thyroiditis (n=7), hyperthyroidism (n=5), systemic lupus erythematosus (SLE, n=3), and rheumatoid arthritis (n=1). Only one relapse occurred due to delayed dosing. The mean EDSS score significantly decreased. Due to the lower disease severity at enrollment and the smaller sample size of patients with concomitant SS and SLE, no significant changes in ESSDAI and SLEDAI scores have been observed. Three patients experienced mild infections: one had transient fever with cough, and two developed chronic cough that resolved within three months. Besides, two SS patients had asymptomatic pulmonary lesion progression. Three of these five patients exhibited low IgG (<5.5 g/L) and IgM (<0.3 g/L) levels, indicating the need for close immunoglobulin monitoring and timely supplementation.

Conclusions:

Inebilizumab effectively prevents relapses and disability progression in NMOSD patients with comorbid autoimmune diseases. It may thus serve as a preferred therapeutic option for this patient population.