After obtaining written informed consent, those patients who are deemed eligible for the study, will be randomized on Day 1, in a double-blinded manner, in a 3:1ratio to receive either oral STP1 (twice daily) or placebo (twice daily). The total study duration is 6 weeks, including a screening phase of up to 2 weeks, a treatment phase of 2 weeks and a post-treatment follow-up phase of 2 weeks.
The main purpose of this study is to evaluate safety and tolerability, Pharmacokinetics and Pharmacodynamics, as well as exploratory efficacy of STP1, in a subgroup of patients with Autism Spectrum Disorder (ASD).