Proof of Concept Study on Pitolisant Effect on Autism Spectrum Disorders in Children and Adolescents

Inclusion Criteria: * Participants and their parent(s)/legal guardian(s) are willing and able to give informed assent and consent for participation in the study. * Male children and adolescents aged from 6 to 17 inclusive for the duration of study participation. * Diagnosis of autism spectrum disorders (ASD) as per the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria confirmed by the Autism Diagnostic Observation Schedule (ADOS-2) or the Autism Diagnostic Interview-Revised (ADI-R). * Intelligence Quotient (IQ) ≥ 70 using Wechsler Intelligence Scale. * Social Responsiveness Scale Second Edition (SRS-2) total T-score ≥ 66 at screening and baseline. Exclusion Criteria: * Previous genetic diagnosis of ASD-known "syndromic" ASD (e.g., Fragile X syndrome, Angelman syndrome, Prader-Willi, Rett's syndrome, tuberous sclerosis, Dup15q syndrome). * History of suicidal behavior or suicidal ideation in the past 12 months, or a positive answer to questions 4 or 5 on the Columbia-Suicide-Severity Rating Scale (C-SSRS) at screening and/or baseline, and/or is a significant risk for suicidal behavior per investigator judgement. * History or current diagnosis of epilepsy or any seizure occurring after the age of 5. * Clinically significant deviation from normal on 12-lead ECG that results in an active medical problem, per investigator judgement or, with a corrected QT interval by Fridericia (QTcF) \> 450ms at screening. * Severe hepatic impairment (Child Pugh C) or with any other hepatic significant abnormality in the physical examination or alanine aminotransferase (ALAT) or aspartate aminotransferase (ASAT) ≥ 2x Upper Limit of Normal (ULN) for age at laboratory results.