The primary objective of this study is to assess the time of onset and time course of
efficacy over 16 hours of PRC-063 compared to placebo in adults diagnosed with ADHD in a
simulated adult workplace environment (AWE) setting, as measured by the PERMP (an
individually-adjusted math test) at pre-dose, 1.0, 2.0, 5.0, 8.0, 11.0, 14.0 and 16.0 hours
post-dose.