OBJECTIVES : This study compared the annualized relapse rates (ARRs) and risk of relapse in patients with multiple sclerosis (MS) on first-line (F-L) oral vs platform disease-modifying therapies (DMTs).

METHODS : Adult patients with MS who newly initiated platform therapies (interferon or glatiramer acetate) and oral therapies (dimethyl fumarate or fingolimod) from January 2011 to December 2017 were identified using IBM MarketScan research databases. The index date was the first DMT claim date. Patients had ≥1-year pre-index and post-index continuous enrollment and ≥1 MS diagnosis prior to or within 30 days post-index. Relapse rates (ARRs) were annualized for the first 3 years post-index. Generalized linear models were used to compare ARRs, and Cox regression was used to estimate the risk of relapse after adjusting for age, gender, index year, Charlson Comorbidity Index score, baseline relapse, and time from earliest MS diagnosis to F-L DMT.

RESULTS : A total of 9,375 MS patients met the study selection criteria; 3,060 patients were treated with F-L oral DMTs and 6,315 were treated with F-L platform DMTs. Patients treated with oral DMTs had significantly lower ARRs than those treated with platform DMTs (year 1 post-index: 0.226 vs 0.185, P<0.0001; years 1-2: 0.208 vs 0.175, P<0.0001; years 1-3: 0.201 vs 0.172, P<0.0001). Similar results were obtained after controlling for covariates (year 1 post-index: 0.217 vs 0.168, P<0.0001; years 1-2: 0.201 vs 0.156, P<0.0001; years 1-3: 0.197 vs 0.149, P<0.0001). F-L oral DMT patients had a reduced risk of experiencing relapse compared with F-L platform patients (year 1: HR=0.822, P<0.0001; years 1-2: HR=0.848, P<0.0001; years 1-3: HR=0.841, P<0.0001).

CONCLUSIONS : These findings suggest that patients newly treated with oral DMTs had lower relapse rates and reduced risk of relapse compared with those treated with platform therapies over the first 3 years of treatment.