To examine the effects of the monoaminergic stabilizer (−)-OSU6162 on mental fatigue in patients with traumatic brain injury.Setting:
Single-center Neurorehabilitation Clinic.Design:
Randomized, double-blind, placebo-controlled trial.Participants:
Sixty-four subjects with traumatic brain injury were randomized to treatment (n = 33) and placebo (n = 31).Main Measures:
The effects of (−)-OSU6162 at a dose of 15 mg twice a day were evaluated using self-assessment scales and neuropsychological tests measuring mental fatigue.Results:
No difference between groups was observed on any scale at baseline. At follow-up, both groups showed significant improvement on the Fatigue Severity Scale and the Mental Fatigue Scale (both Ps < .01). Similarly, the performance of both groups increased significantly on many neuropsychological tests. However, no significant between-group difference in changes on these scales was observed before or after adjustment for confounders except for one neuropsychological test favoring the control group. Sensitivity analyses showed significantly greater changes in levels of prolactin and folic acid and heart rate (all Ps < .05) in the treatment group. The mean plasma concentration after 4 weeks of treatment was 0.14 (range, 0.01–0.32) µM, which was lower than expected.Interpretation:
Treatment with (−)-OSU6162 had no significant effect on mental fatigue in patients with traumatic brain injury compared with placebo.