Initiation Patterns of Disease-Modifying Therapies for Multiple Sclerosis among US Adults and Children, 2001 Through 2020

Abstract

Importance: Many disease-modifying therapies (DMTs) have been approved for multiple sclerosis (MS) in the past 2 decades. Research evaluating how these approvals have changed real-world prescribing patterns is scarce. Objective: To evaluate patterns in DMT initiations between 2001 and 2020 among commercially insured US adults and children with MS. Design, Setting, and Participants: This serial cross-sectional study was conducted from 2001 through 2020 (mean patient enrollment duration, 4.8 years) and used US commercial claims data (MarketScan). Analysis took place between January 2022 and March 2023. Of 287084 patients with MS identified, 113583 patients (113095 adults and 488 children) with MS newly initiated at least 1 DMT. Exposure: New initiation episode of a DMT, defined as no claim for the same DMT in the previous year. Main Outcome Measure: The proportion of total DMT initiations per year attributable to each DMT. Trends in initiations were evaluated annually. Results: The study team identified 153846 DMT initiation episodes among adults (median age, 46 [IQR, 38-53) years]; 86133 female [76.2%]) and 583 among children (median age, 16 (IQR, 14-17) years; 346 female [70.9%]). Among adults, use of platform injectables showed an absolute decline of 73.8% over the study period, driven by a 61.2% reduction in interferon β initiations (P