A 6 Week Study of MG01CI 1400 mg Compared With Placebo in Adults With ADHD ( Attention Deficit/Hyperactivity )

Inclusion Criteria: * Subject is a man or a non-pregnant, non-lactating woman 18 to 55 years of age, inclusive, at the Screening Visit. * Subject has a diagnosis of ADHD based on criteria in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) and DSM5. * Subject has ADHD with at least moderate clinical severity (Clinical Global Impression-Severity \[CGI-S\]) score of 4 or greater). * Subject has a score on the total ADHD symptom score with adult prompts of the CAARS-Inv of at least 22. * Female subjects of childbearing potential must agree to use an effective contraceptive throughout the study * Subject is able to attend the clinic regularly and reliably. * Subject is able to swallow tablets and capsules. * Subject is able to understand, read, write, and speak English fluently to complete the study-related materials (or Hebrew for Israeli subjects). * Subject is able to understand and sign an informed consent form to participate in the study. Exclusion Criteria: * Subject did not respond in the past to 2 adequate trials of stimulant treatments or 1 adequate trial of atomoxetine treatment (in the investigator's judgment). * Subject has any psychiatric condition clinically significant or unstable medical or surgical condition that may preclude safe and complete study participation as determined by the investigator . * Subject has a known or suspected human immune deficiency virus-positive status or has diseases such as acquired immunodeficiency…