Cost of Patients with Multiple Sclerosis Newly Initiating Subcutaneous Interferon ß-1a Vs Oral Disease-Modifying Drugs – a Real-World Assessment
Objectives: To utilize real-world data to evaluate costs among patients with multiple sclerosis (MS) initiating subcutaneous interferon beta-1a (scIFNβ1a) vs oral disease-modifying drugs (DMDs; ie, teriflunomide, fingolimod, dimethyl fumarate).
Methods: Patients with third party payer coverage were identified from the IMS LifeLink PharMetrics Plus™ Database from 1/1/2012–6/30/2013. Inclusion criteria were: MS diagnosis (ICD-9-CM:340.xx); initiation of scIFNβ1a, teriflunomide, fingolimod, or dimethyl fumarate (1st claim=index date); continuous eligibility 12 months pre- and post-index; no DMD 12 months pre-index (treatment-naïve); and age 18–63 years. Total (all-cause) and medical costs (excluding DMD costs) were assessed during the 12-month post-index period (reported in 2014 US dollars). Generalized linear models with gamma distribution and log link assessed cost controlling for demographics (ie, age, sex, and region) and clinically-meaningful measures of disease severity (ie, 90-day pre-index indicators for relapse, neurologist visits, and MRI).
Results: A total of 1665 patients (686 scIFNβ1a, 118 teriflunomide, 455 fingolimod, and 406 dimethyl fumarate) met inclusion criteria (mean age=44.4 years; 75.5% female; 28.0% Northeast, 35.0% Midwest, 29.8% South, and 7.1% West). After adjustment for demographics and clinically meaningful disease severity indicators, the estimated least square mean 12-month total cost for scIFNβ1a was $57,558 compared with teriflunomide ($55,414; p=0.4977), fingolimod ($69,478; p<0.0001) and dimethyl fumarate ($69,798; p<0.0001). The estimated least square mean 12-month medical cost for scIFNβ1a was $13,562 compared with fingolimod ($15,840; p=0.0234), teriflunomide ($17,148; p=0.0350), and dimethyl fumarate ($20,987; p<0.0001).
Conclusions: In this real-world MS patient population, after controlling for demographics and clinically-meaningful measures of disease severity, 12-month total cost was significantly lower in patients initiating scIFNβ1a compared with those initiating fingolimod or dimethyl fumarate, and 12-month medical cost was significantly lower in patients initiating scIFNβ1a compared with patients initiating any oral DMD.