FACTORS ASSOCIATED WITH SWITCHING FROM INJECTABLE TO ORAL DISEASE MODIFYING AGENTS AMONG PATIENTS WITH MULTIPLE SCLEROSIS

Abstract

Background: Since the introduction of oral disease-modifying agents (DMA) in 2010, the treatment options for multiple sclerosis (MS) have changed significantly. There is limited information regarding the factors associated with switching to oral DMA among prevalent injectable DMA users.

Objective: This study evaluated the factors associated with switching to oral DMAs among prevalent injectable DMA users with MS.

Methods: A retrospective observational cohort study using the TriNetX electronic medical records (EMR) data was conducted among patients with MS. The study included prevalent injectable DMA users with at least two injectable DMA (interferon beta-1a, interferon beta-1b, peginterferon beta-1a, or glatiramer acetate) prescription records within 6 months between September 2010 and May 2018. The second injectable DMA prescription date was considered as the index date. Switching was defined as any oral DMA prescription record (fingolimod, dimethyl fumarate, or teriflunomide) within 12 months after the index date. Patients with any infusion DMA prescription after the first injectable DMA prescription, and those less than 18 years of age were excluded from the study. The Andersen Behavioral Model was used as the conceptual framework to identify predisposing, enabling, and need factors measured during the 1-year baseline period before the index date. A multivariable logistic regression model was used to examine the predisposing (age, sex, race, and ethnicity), enabling (time-period), and need factors (comorbidities, MS symptoms, MS-related medication, and healthcare utilization) associated with switching from injectable to oral DMAs.

Results: Among 2,943 prevalent injectable users included in this study, 8.09% (n=238) patients switched to oral DMAs. Patients who switched to oral DMAs were primarily younger adults aged 18-44 years (64.29%), females (82.77%), had sensory and visual symptoms, and had corticosteroid utilization during the one-year look-back period compared to non-switchers. Results from multivariable logistic regression model revealed that middle-aged adults (45-64 years, adjusted odds ratio [aOR]: 0.43, 95% Confidence Interval [CI]: 0.32-0.58), old adults (≥65 years, aOR: 0.30, 95% CI: 0.13-0.66) and men (aOR: 0.67, 95% CI: 0.47-0.96) were associated with decreased odds of switching to oral DMAs. Presence of MS-related sensory symptoms (aOR: 1.52, 95% CI: 1.07-2.16), visual symptoms (aOR: 1.59, 95% CI: 1.10-2.31), and corticosteroids usage (aOR: 1.44, 95% CI: 1.04-1.98) were associated with increased odds of switching to oral DMAs.

Conclusion: The study found that about one in twelve prevalent injectable DMA users switched to oral DMA. Both demographic and clinical factors were associated with switching to oral DMAs. Further research is needed to evaluate the outcomes of switching to inform treatment decisions for MS management.

Keywords: Disease-modifying agents; Multiple Sclerosis; Switching; Treatment Pattern.