Real-World Assessment of Relapse Rates in Patients with Multiple Sclerosis Newly Initiating Subcutaneous Interferon β-1a vs Oral Disease-Modifying Drugs (P6.178)

Objective: Utilize ‘real-world’ data to evaluate relapse rates of patients with multiple sclerosis (MS) newly initiating subcutaneous interferon β-1a (scIFNβ1a) vs oral disease modifying drugs (DMDs). Background: Retrospective database studies can provide valuable information regarding ‘real-world’ outcomes. Methods: Patients from IMS LifeLink PharMetrics Plus™ were selected 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 claims 12 months pre-index (treatment-naive); and age 18-63. Relapse (assessed 12 months following DMD initiation) was defined as: MS-related hospitalization, MS-related ER visit, or MS-related outpatient visit with corticosteroid prescription ±7 days. Analyses included pairwise chi-square tests and logistic regression controlling for age, sex, region, and disease severity (ie, 90-day pre-index indicators for relapse, neurologist visits, and MRI). Results: 1665 patients met inclusion criteria (mean age=44.4; 75.5[percnt] female). Unadjusted analyses showed no differences in MS-related hospitalizations or ER visits among DMDs. Unadjusted rates of MS-related outpatient relapse were lower in patients initiating scIFNβ1a (19.7[percnt]) vs teriflunomide (32.2[percnt]; p=0.003) and dimethyl fumarate (26.8[percnt]; p=0.006). Proportions of patients with ≥1 MS relapse were lower with scIFNβ1a vs oral DMDs (21.7[percnt] and 26.1[percnt], respectively; p = 0.039). Logistic regression controlling for demographic and 90-day pre-index indicators showed that, vs scIFNβ1a, teriflunomide or dimethyl fumarate initiation were associated with a higher likelihood of relapse (odds ratio [OR]=2.1; p=0.001 and OR=1.5; p=0.005, respectively). A neurologist visit (p=0.034) and MS relapse (p<0.0001) within 90 days before treatment initation were predictive of relapse. Conclusions: In ‘real-world’ assessment of this MS population, patients initiating scIFNβ1a had lower likelihood of experiencing relapse surrogates over Year 1 than patients initiating teriflunomide or dimethyl fumarate. Study supported by: EMD Serono, Inc., Rockland, MA, USA (a subsidiary of Merck KGaA, Darmstadt, Germany); Pfizer Inc, New York, NY, USA. Disclosure: Dr. Kozma has received personal compensation for activities with Health Services Research as a consultant. Dr. Munschauer has received personal compensation for activities with EMD Serono, Inc., as an employee. Dr. Phillips has received personal compensation for activities with EMD Serono, Inc. as an employee.