Diroximel fumarate (DRF) is a novel oral fumarate for relapsing forms of multiple sclerosis (MS). DRF is converted to monomethyl fumarate (MMF), the same pharmacologically active metabolite as dimethyl fumarate (DMF). Oral administration of DRF 462mg and DMF 240mg produce bioequivalent MMF exposure and are therefore expected to exhibit comparable efficacy and safety profiles. DRF has an improved gastrointestinal (GI) tolerability profile compared to DMF.
To report interim safety, tolerability, and efficacy outcomes in DRF-treated patients from EVOLVE-MS-1 and to assess GI tolerability in a subgroup of patients who received DMF prior to DRF.
EVOLVE-MS-1 (NCT02634307) is an ongoing, open-label, 96-week study assessing DRF safety, tolerability, and efficacy in adults with relapsing-remitting MS. Patients entered the study either as newly enrolled in the DRF clinical development program or after completing EVOLVE-MS-2 (NCT03093324), a randomized, blinded, phase 3 study in which patients received DRF or DMF over 5 weeks.
As of 2 July 2019, 1051 patients were enrolled, 458 of whom had completed EVOLVE-MS-2. Median DRF exposure was 1.5 (range 0.0-1.9) years. Overall, 44.2% of patients completed the study and 17.3% discontinued treatment; 6.3% discontinued due to AEs and 0.7% due to GI AEs. AEs occurred in 82.1% (863/1051) of patients; 90% (779/863) were mild or moderate in severity. Incidence of GI AEs was 28.4% (299/1051) in the overall population, 21.7% (51/235) in patients with prior DRF treatment, and 21.5% (48/223) in patients with prior DMF treatment. Patients who had experienced GI AEs in EVOLVE-MS-2 (DRF to DRF, 33.6% [79/235]; DMF to DRF, 44.8% [100/223]) had low rates of recurrence (3.4% [8/235] and 3.6% [8/223] for those previously treated with DRF and DMF, respectively) and/or onset of new GI AEs (19.6% [46/235] and 20.6% [46/223], respectively) in EVOLVE-MS-1, regardless of prior treatment group. In the overall population (n=1051), annualized relapse rate was 0.14, and 86.1% of patients were relapse-free. Outcomes in patients who were newly diagnosed or most recently switched from interferon or glatiramer acetate will be presented.
Safety and efficacy results from the ongoing EVOLVE-MS-1 study were consistent with previous findings of DRF and the known benefit-risk profile for DMF. In patients who switched from DMF to DRF, no worsening of tolerability was observed.
Supported by: Biogen