OBJECTIVES: To compare multiple sclerosis (MS) related healthcare use within one year of initiating first and second generation disease modifying therapies (DMTs) among individuals diagnosed with MS in the U.S.

METHODS: A large national sample of patient-level administrative healthcare claims data were used for this analysis. MS patients aged 18 years and over with a new prescription fill for a first or second generation DMT between 2013 and 2015 were evaluated. First generation DMTs included interferon beta-1b and glatiramer acetate (GA). Second generation DMTs included teriflunomide, dimethyl fumarate, natalizumab, novantrone, interferon beta-1a, peginterferon beta-1b, and fingolimod. Patients were eligible if they were continuously enrolled in a health plan with pharmacy and medical coverage for at least 6 months before and 1 year after initiation of therapy. Three types of healthcare use were examined: MS-related hospitalizations and relapse events (inpatient and outpatient). Multivariate Poisson and Zero-inflated Poisson models with robust standard errors were used to estimate the association between MS-related healthcare use and type of DMT. All models adjusted for age, gender, Charlson index, geographic region and payer type.

RESULTS: During the study period, 18,946 individuals with a MS diagnosis initiated a DMT. Of those, 77.3% were female, 66.3% were ages 40-64 years, and 53.3% had commercial health insurance. Almost two-thirds (62.9%) were on second generation DMTs. Second generation DMT users were found to have fewer MS-related hospitalizations compared to first generation DMT users within one year of initiating therapy (adjusted risk ratio (ARR)= 0.91 (95% confidence interval (CI): 0.88-0.97)). Differences in inpatient and outpatient relapses were not observed by DMT type.

CONCLUSIONS: This study suggests that second generation DMTs are associated with reduced MS-related hospitalizations within one year of initiating therapy. Studies examining a longer treatment timeframe and additional healthcare outcomes are warranted to confirm these findings.