Exposure response to VEC-162 on induction of circadian phase shift as measured by Dim Light Melatonin Onset (DLMO) was defined as the time change between Night 3 and Night 4 when melatonin production reached 25% of the maximum melatonin concentration. Samples below LOQ of the melatonin assay were assigned 5 pg/ml.

Exposure response was measured by comparing the change in sleep efficiencies of VEC-162 and placebo treated subjects upon a sleep schedule phase advance. Sleep efficiency (total time asleep divided by the time allowed as an opportunity for sleep in a period multiplied by 100%, where time allowed for sleep was 8 hours or 480 minutes) was measured objectively by overnight polysomnographic recordings. Sleep efficiency was also compared in parts of the night by dividing the full night into thirds.

Wake After Sleep Onset is defined as the total time that is scored as awake in a PSG occurring between sleep onset and lights-on prompt.

Latency to Persistent Sleep is defined as the number of epochs (one 30-second interval of the sleep episode) from the beginning of the recording (lights-out) to the start of persistent sleep (first 20 consecutive non-wake state) divided by 2.

Randomized to Placebo

Randomized to 10 mg VEC-162

Exposure response to VEC-162 on induction of circadian phase shift as measured by Dim Light Melatonin Onset (DLMO) was defined as the time change between Night 3 and Night 4 when melatonin production reached 25% of the maximum melatonin concentration. Samples below LOQ of the melatonin assay were assigned 5 pg/ml.

Randomized to Placebo