Critical Therapeutics reports positive results of Phase I trial of Zileuton

The Phase I clinical trial was a randomized, open-label, single dose, single center, two-period crossover trial designed to examine the safety, tolerability, pharmacokinetic and pharmacodynamic profile of the R(+) isomer of zileuton in healthy subjects.

Twelve subjects each received two dose levels of the R(+) isomer of zileuton (100 and 300mg) in a randomized, crossover design. Both dose levels of R(+) zileuton were well tolerated with no serious adverse events or clinical safety concerns reported in this trial.

Pharmacokinetic data obtained for R(+) zileuton, dosed alone to humans for the first time, exhibited dose proportionality and matched historical data obtained for R(+) zileuton following equivalent doses of racemic zileuton in earlier clinical trials. The pharmacokinetic profile of R(+) zileuton obtained in the currently reported trial confirmed that it constitutes about two-thirds of the plasma exposure observed with racemic zileuton and is the more persistent isomer of zileuton.