Multiple sclerosis hospitalizations among users of oral disease-modifying therapies

Oral disease-modifying therapies, namely dimethyl fumarate, fingolimod and teriflunomide, have become standard treatments for multiple sclerosis. Clinical trials demonstrated a reduction in annual relapse rate, but real-world data is lacking, particularly in older adults. The objective of our study is to evaluate the real-world effectiveness of oral disease-modifying therapies among individuals with multiple sclerosis.

We used Optum^TM Clinformatics^TM Data Mart, a large dataset representative of commercially insured individuals in the United States, to conduct a retrospective cohort study of adult users of three oral disease-modifying therapies from September 2010 through September 2015. The therapies of interest included dimethyl fumarate, teriflunomide, and fingolimod. Hospitalization for multiple sclerosis, an approximation of the clinical trial endpoint for relapse, was the study outcome. Cox proportional hazards models were built to evaluate the association of demographic and clinical factors with multiple sclerosis hospitalization. A subgroup analysis was performed on individuals ages 55 years or older.

We identified 1,823, 318, and 1,156 users of dimethyl fumarate, teriflunomide, and fingolimod that met our inclusion criteria, respectively. Rates of hospitalizations for multiple sclerosis were low among these 3,297 persons (1,041 ages 55+): 36/1,000 patient-years for dimethyl fumarate, 43/1,000 for teriflunomide, and 45/1,000 for fingolimod. Multiple sclerosis hospitalization was associated with therapy switching (adjusted hazard ratio 2.21, 95% confidence interval 1.57-2.84), minority (1.44, 1.10-1.89), and history of relapse in the year preceding oral therapy initiation (5.25, 3.89-7.09).

Oral disease-modifying therapies are comparably effective for the outcome of multiple sclerosis hospitalization, even in older adults.