NMDA Receptor Modulation for Hyperarousal in PTSD

This study aims to provide a rigorous test of functional target engagement and "go/no go" milestones for a subsequent POC trial. Investigator will conduct a parallel-arm, randomized, double-blind, placebo-controlled study to assess lanicemine (100 mg) with respect to a functional pharmacodynamic readout of target engagement (APS). Twenty-four patients with significant PTSD symptoms and elevated APS will be randomized to one of 2 treatment groups \[placebo or 100 mg\], and undergo three 60 min parenteral infusions over a 5 day period. APS and other neurophysiological biomarkers will be tested before and after the 1st and 3rd treatment. Primary Objective is to examine, relative to placebo, whether lanicemine will demonstrate normalization of the APS response following three treatments. Secondary Objectives are to examine, relative to placebo, whether lanicemine will demonstrate effects on P50 auditory evoked potentials, gamma band EEG, and Mismatch Negativity. Investigator also explore whether target engagement will mediate the effect of treatment on CAPS-5 scores.