(380) Treatment patterns among patients with Neuromyelitis Optica Spectrum Disorder (NMOSD): A real-world evidence study

Background: : Neuromyelitis optica spectrum disorder (NMOSD) is a rare, inflammatory, autoimmune condition that primarily affects the optic nerves and spinal cord. Treatment for NMOSD focuses on the management of acute attacks and prevention of relapses.

Objective: : To describe current treatment patterns among patients with a diagnosis of NMOSD.

Methods: : This study was an observational, retrospective analysis of the MORE2 Registry® and 100% Medicare Fee-for-Service databases spanning 6/11/2019 to 12/31/2023. Inclusion criteria were as follows: ≥ 2 claims with a diagnosis of NMOSD, or ≥ 1 claim with a diagnosis of NMOSD, transverse myelitis, or optic neuritis + ≥ 1 claim for treatment (earliest diagnostic evidence = index date), 2) ≥18 years of age on the index date, and 3) ≥12 months of continuous enrollment prior to and ≥6 months following the index date. Maintenance NMOSD treatment lines of therapy (LoTs) were assessed, and treatment patterns were reported which included the time to treatment, duration of therapy, time to next treatment, co-administration with steroids, and switching.

Results: : A total of 3,130 patients qualified for the study, with a mean (SD) age of 53.2 (16.9) years old, and the majority being female (80.7%) receiving Medicare benefits (57.8%). Three-fourths of patients (74.6%) received an initial LoT, while 51.6% showed a second LoT (396.3 [273.1] days after the initial LoT). The majority of LoT 1 and LoT 2 regimens were off-label treatments (86.2% and 79.7%), and most were for biologic monotherapy (72.9% in LoT1, and 61.3% in LoT2). The most common biologics were rituximab (LoT1 54.6%; LoT2 43.9%), eculizumab (LoT1 6.7%; LoT2 5.6%), and inebilizumab-cdon (LoT1 4.1%; LoT2 5.1%). Utilization of combination therapy was more frequent during LoT 2 compared to LoT 1 (12.5% vs. 2.0%). Patients receiving inebilizumab-cdon were the least likely to switch to another maintenance medication ( < 10%), compared to those receiving rituximab (11.0%) and eculizumab (19.8%). During LoT 1, receipt of oral steroids was more frequent among patients receiving rituximab (40.7%) and eculizumab (40.8%) compared to patients receiving inebilizumab-cdon (34.4%).

Conclusions: : The majority of patients with NMOSD received off-label treatment, largely with biologic monotherapy. Switching, a key indicator of suboptimal disease management, was least common among patients on inebilizumab-cdon. As patients remain on therapy for well over a year, findings emphasize the importance of appropriate treatment selection early in the patient journey.

Sponsorship:: Amgen Inc.