Allopregnanolone for the Treatment of Traumatic Brain Injury

This is a double-blind, placebo-controlled, randomized, dose-finding, two-stage adaptive, clinical trial study comparing allopregnanolone to placebo when administered intravenously for 5 days beginning within 8 hours after injury. Test products to be administered are low and high dose allopregnanolone (Products L and H, respectively) and placebo (Product P) intravenous solutions. The products are administered during a 4-day treatment period followed by a 1-day dose de-escalation period. Stage 1 of the study will assess safety and confirm that dosing with Products L and H achieve the target steady-state plasma concentrations set for each of these products. Dosing will be adjusted in Stage 1, if necessary. Stage 2 will initially allocate subjects equally to Products L, H and P but will then use adaptive randomization to allocate subjects between Products L and H to optimized the probability of yielding a better 3-month Glasgow Outcome Score Extended (GOS-E) score.