Diroximel Fumarate in Patients with Relapsing-Remitting Multiple Sclerosis: NEDA-3 After Re-Baselining in the Phase 3 EVOLVE-MS-1 Study.

Introduction: Diroximel fumarate (DRF) and dimethyl fumarate (DMF) are orally administered fumarate disease-modifying therapies (DMTs) for multiple sclerosis (MS). The safety, tolerability, and exploratory efficacy of DRF were evaluated in the phase 3 EVOLVE-MS-1 study. No Evidence of Disease Activity (NEDA-3) is a composite efficacy endpoint used in clinical trials for MS defined as no relapse, no 24-week confirmed disability progression (CDP), no new/newly enlarging T2 lesions, and no new gadolinium-enhancing lesions. As NEDA outcomes in studies may be confounded by initial disease activity, the objective of this analysis was to evaluate NEDA-3 in EVOLVE-MS-1 for newly enrolled patients and patients who were re-baselined after approximately 7 weeks.

Methods: Patients entered EVOLVE-MS-1 as either newly enrolled or having completed the 5-week phase 3 EVOLVE-MS-2 study of DRF and DMF. Magnetic Resonance Imaging (MRI) was performed at baseline before each study (approx. 7 weeks apart) and at weeks 48 and 96 in EVOLVE-MS-1. Therefore, patients entering from EVOLVE-MS-2 were re-baselined after approximately 7 weeks. NEDA-3 outcomes on DRF are reported for prior DRF, prior DMF, and de novo patient groups.

Results: Of 1057 patients in EVOLVE-MS-1, 239 (22.6%) had rolled over from receiving DRF in EVOLVE-MS-2 ("prior DRF"), 225 (21.3%) had rolled over from receiving DMF in EVOLVE-MS-2 ("prior DMF"), and 593 (56.1%) were newly enrolled ("de novo"). At week 48, Kaplan-Meier estimates of NEDA-3 were 72.3% (prior DRF), 72.1% (prior DMF), and 62.1% (de novo); at week 96, estimates were 50.2% (prior DRF), 48.2% (prior DMF), and 36.5% (de novo).

Conclusions: In EVOLVE-MS-1, after re-baselining at approximately 7 weeks, approximately half of DRF-treated patients achieved NEDA-3 at week 96, compared with 36.5% of patients who were not re-baselined. Re-baselining may be useful for assessing efficacy of DMTs by mitigating the influence of disease activity prior to the onset of efficacy.

Clinical Trial Registrations: NCT03093324 (EVOLVE-MS-2); NCT02634307 (EVOLVE-MS-1).