Bioequivalence Study of Oral Suspension and Intravenous Formulation of Edaravone in Healthy Adult Subjects.

The neuroprotective agent edaravone is an intravenous treatment for amyotrophic lateral sclerosis. As intravenous administration burdens patients, orally administered treatments are needed. This phase 1, open-label, single-dose crossover study in 42 healthy adults evaluated bioequivalence of a 105-mg edaravone oral suspension and intravenous edaravone (60 mg/60 min). The evaluation was whether the 90% confidence intervals (CIs) for the ratio of the maximum plasma concentration (Cmax ) and area under the plasma concentration-time curve from time 0 to the last quantifiable time point and to infinity of unchanged edaravone were between the bioequivalence limit of 0.80 and 1.25. Metabolic profiles and elimination pathways were also compared between the 2 routes. Geometric mean ratios and 90%CIs of area under the plasma concentration-time curve from time 0 to the last quantifiable time point and to infinity for unchanged edaravone satisfied bioequivalence limits. The geometric mean ratio and its lower limit of 90%CI of Cmax of the 105-mg oral suspension compared with 60-mg intravenous formulations for unchanged edaravone fell within bioequivalence limits. Both formulations showed triphasic plasma concentration-time profiles of unchanged edaravone after reaching Cmax . Plasma concentrations of edaravone inactive metabolites after oral administration were higher than with intravenous administration. Edaravone in both routes underwent urinary excretion, mainly as the glucuronide conjugate and, to a lesser extent, as the sulfate conjugate. Urinary excretion of unchanged edaravone was low, and urinary relative composition ratios of unchanged edaravone and metabolites were similar for both formulations. These findings showed equivalent exposure of the 105-mg oral suspension of edaravone to the 60-mg intravenous formulation, supporting further investigation of the oral suspension for treating amyotrophic lateral sclerosis.

Evaluation of Pharmacokinetics, Safety, and Drug-Drug Interactions of an Oral Suspension of Edaravone in Healthy Adults.

Intravenous (IV) edaravone is approved as an amyotrophic lateral sclerosis (ALS) treatment. Because IV administration places a burden on patients, development of orally administered ALS treatments is needed. Therefore, 2 phase 1 studies of oral formulations of edaravone in healthy subjects examined the pharmacokinetics (PK), safety, racial differences, and drug-drug interactions (DDIs) and investigated the dose of the oral formulation considered to be bioequivalent to the approved dose of the IV formulation. Study 1 was a placebo-controlled, randomized, single-blind study of single-ascending-dose oral edaravone with the dose range of 30 to 300 mg (n = 56). Study 2 was conducted in 2 cohorts (n = 84); the first assessed DDIs with multiple-dose edaravone 120 mg/day given over 5 or 8 days (coadministered with single-dose rosuvastatin, sildenafil, or furosemide), and the second evaluated PK and racial (Japanese/White) differences in PK parameters with doses of 100-mg edaravone. The oral formulation of edaravone was well absorbed, and plasma concentrations of unchanged edaravone increased more than dose proportionally within the dose range of 30 to 300 mg. No effect of race on oral edaravone PK and no notable DDI effects possibly caused by orally administered edaravone were observed. The oral edaravone formulations were safe and tolerable under the assessed conditions. Mathematical modeling determined that equivalent exposures in plasma with the approved dose of the IV edaravone formulation, as reported previously, could be achieved when the oral edaravone formulation was administered at a dose of  ≈100 mg, with an absolute bioavailability of ≈60%.