ABSTRACT
INTRODUCTION: Adherence to disease-modifying therapies is key for achieving optimal outcomes in multiple sclerosis (MS). Diroximel fumarate (DRF) is an oral fumarate approved for treatment of relapsing forms of MS. It has the same pharmacologically active metabolite as dimethyl fumarate (DMF) and similar efficacy and safety profiles, but with demonstrated fewer gastrointestinal (GI) related adverse events (AEs). There are limited data characterizing persistence and adherence to DRF in the real world. METHODS: This retrospective analysis of the AcariaHealth Specialty Pharmacy Program included patients with MS initiating DRF from 1 December 2019 to 30 January 2021. This analysis evaluated persistence, measured as proportion of patients remaining on therapy; discontinuation rate due to GI AEs; and adherence measured by proportion of days covered (PDC). RESULTS: Overall, 1143 patients were included; 433 (37.9%) patients had been treated with prior DMF and switched to DRF. Persistence was high in both groups: the estimated proportion of patients remaining on DRF at 16 months was 82.3% [95% confidence internal (CI) 77.2-86.3%], and 90.1% (95% CI 82.2-94.6%) in the DMF to DRF group. Fifty-two (4.5%) patients overall and 15 (3.5%) in the DMF switch subgroup discontinued DRF due to GI AEs. Mean PDC was 90.8% (95% CI 89.2-92.5%), and 85.4% (95% CI 83.3-87.4%) of patients achieved PDC ≥ 80% in the overall population. In the DMF to DRF group, mean PDC was 90.7% (95% CI 88.0-93.5%), and 84.8% (95% CI 81.4-88.1%) of patients achieved PDC ≥ 80%. CONCLUSION: In this analysis of > 1000 patients treated with DRF in real-world clinical practice, overall persistence at 16 months was high, treatment discontinuation due to GI AEs was low, and patients were highly adherent to therapy. Of 433 patients who switched from DMF to DRF, most (> 90%) were able to tolerate and persist on DRF after switching. Graphical abstract available for this article.
ABSTRACT
INTRODUCTION: Persistence to multiple sclerosis (MS) disease-modifying therapy is fundamental for maximal treatment outcomes. Diroximel fumarate (DRF) is approved in the USA for relapsing MS. Following oral administration, DRF is metabolized to monomethyl fumarate, the active metabolite of dimethyl fumarate (DMF). DRF showed clinically significant improvements in gastrointestinal (GI) tolerability versus DMF in a head-to-head clinical trial; however, real-world persistence/adherence has not been assessed. We evaluated persistence/adherence in DRF-treated patients in a real-world clinical practice. METHODS: This retrospective analysis of the AcariaHealth Specialty Pharmacy Program included patients initiating DRF from 4 December 2019 through 3 April 2020 and followed until data extraction (31 August 2020). Exclusion criteria included undetermined treatment status (e.g., DRF prescription transfer to a different pharmacy). Endpoints included persistence (overall proportion of patients remaining on DRF), discontinuation rate due to GI adverse events (AEs), and adherence (proportion of days covered [PDC]). GI AEs included GI-related AEs occurring at any time, or any unknown AE without details about the nature of the event if the unknown AE occurred ≤ 90 days after DRF initiation. RESULTS: Overall, 160 patients with MS were included. Median (range) patient age was 51 (20-79) years, 80.6% (129/160) of patients were female, and 16.3% (26/160) had prior DMF treatment. Median (range) treatment duration was 7.6 (0.1-10.4) months. Estimated proportion of patients remaining persistent on DRF treatment at 8 months was 88.6% (95% confidence interval [CI] 82.5-2.7). Overall, 3.8% (6/160) of patients discontinued due to GI AEs. Mean PDC was 91.4% (95% CI 89.1-93.7). In a DMF-to-DRF switch subgroup, 92.3% (24/26) remained persistent on DRF, and 3.8% (1/26) discontinued DRF due to GI AEs. CONCLUSION: This real-world analysis of DRF-treated patients showed high overall persistence, low discontinuation rate due to GI AEs, and high adherence to therapy, aligning with expectations based on DRF clinical trials. Data were consistent in the DMF-to-DRF subgroup. INFOGRAPHIC.