Pharmacokinetics and Bioavailability of Monomethyl Fumarate Following a Single Oral Dose of Bafiertam™ (Monomethyl Fumarate) or Tecfidera(®) (Dimethyl Fumarate)

BACKGROUND: Tecfidera(®) (dimethyl fumarate [DMF]) is an approved product for the treatment of relapsing forms of multiple sclerosis. Monomethyl fumarate (MMF) is the only active metabolite of DMF and is responsible for its therapeutic efficacy. OBJECTIVE: The objective of this study was to determine whether two Bafiertam™ capsules each containing 95 mg of MMF is bioequivalent to one Tecfidera(®) capsule containing 240 mg of DMF, a prodrug of MMF. METHODS: This was a single-dose, open-label, randomized, two-way crossover study evaluating two treatments over two periods with a washout interval between treatments. Fifty healthy subjects were randomized to receive a single dose of the test drug MMF 190 mg as 2 × 95 mg delayed-release capsules or the reference drug DMF 240 mg as a 1 × 240-mg delayed-release capsule. Blood samples were obtained prior to dosing and at prespecified time points through 24 h post-dose to determine plasma concentrations of MMF. The pharmacokinetic parameters of MMF were calculated including maximum observed concentration, time to reach maximum observed concentration, apparent half-life of the drug in plasma, AUC(0–t) which is the area under the plasma concentration–time curve (AUC) from time zero (dosing time) to the last time point, t, with measurable analyte concentration, and AUC(0–inf), which is AUC(0–t) plus the extrapolated AUC from time t to infinity. RESULTS: The geometric least-squares mean ratios (90% confidence interval) of the test drug MMF vs the reference drug DMF were 96.80% (92.18–101.64), 96.35% (91.81–101.12), and 104.84% (95.54–115.05) for AUC(0–t), AUC(0–inf), and maximum observed concentration, respectively. Two capsules of Bafiertam™ was safe and generally well tolerated. The most common adverse event for both products was flushing, 60% and 51%, for Bafiertam™ and Tecfidera(®), respectively. CONCLUSIONS: Based on the statistical analysis results of the pharmacokinetic parameters of MMF, a single oral dose of two Bafiertam™ DR 95 mg capsules is bioequivalent to a single oral dose of one Tecfidera(®) DR 240 mg capsule. CLINICAL TRIAL REGISTRATION: This study was retrospectively registered with ClinicalTrials.gov (NCT04570670) on 30 September, 2020.