Efficacy, Safety & Pharmacokinetic (PK) Study of HLD200 in Children Aged 4-5 Years With ADHD

Exclusion criteria

• . History of, or current, medical or psychiatric condition, including gastrointestinal disorders (e.g., surgery, malabsorption syndrome, and other similar conditions), open-angle glaucoma, abnormally increased intraocular pressure (IOP), or laboratory result that, in the opinion of the Investigator, unfavorably alters the risk-benefit of study participation, may jeopardize subject safety, or may interfere with the satisfactory completion of the study and study related procedures.
• . Serious structural cardiac abnormalities, cardiomyopathy, serious heart rhythm abnormalities, severe hypertension, untreated thyroid disease, peripheral vasculopathy, known structural cardiac disorders, serious cardiac conditions, serious arrhythmias, known family history of sudden death, or other cardiac problems that may place the subject at increased vulnerability to the sympathomimetic effects of a stimulant drug.
• . History of, or current, seizure disorder (except febrile seizures prior to age 4 and with last occurrence at least 1 year prior to study participation) or intellectual disability of mild severity or greater (DSM-5 criteria).
• . Past or current diagnosis of psychosis, bipolar I or II disorder, major depressive disorder, eating disorder, conduct disorder, obsessive-compulsive disorder, autism spectrum disorder, Tourette's Syndrome or other tic disorders, disruptive mood dysregulation disorder, or confirmed genetic disorder with cognitive and/or behavioral disturbances. Subjects with oppositional defiant disorder (ODD) or anxiety disorder (e.g., separation anxiety disorder simple phobia disorder) are permitted to enroll in the study provided these diagnoses are not the primary focus of treatment, and, in the opinion of the Investigator, are not anticipated to interfere with study assessments or procedures.
• . Subject is currently considered at risk of suicide in the opinion of the Investigator, or has previously made a suicide attempt, or has a history of, or is currently demonstrating active suicidal ideation or behavior, as determined by the C-SSRS at Screening and/or Baseline (Visit 2).
• . History of severe allergic reaction or intolerance to methylphenidate hydrochloride (MPH).
• . Alanine aminotransferase, aspartate aminotransferase, total bilirubin, or creatinine greater than 1.5 times the upper limit of normal. Elevated bilirubin due to Gilbert's syndrome is not exclusionary.
• . Use of ADHD stimulant medication within 72 hours (3 days) prior to Baseline (Visit 2); clonidine and guanfacine within 5 days prior to Baseline (Visit 2); psychotropic medications, including antidepressants (including MAOIs), mood stabilizers, and antipsychotics, within 14 days prior to Baseline (Visit 2); other prescription medications (including atomoxetine, excluding allowed medications) within 7 days prior to Baseline (Visit 2); and nonprescription/over-the-counter medications (excluding allowed medications) or herbal medications within the 3 days prior to Baseline (Visit 2). Medications not covered in allowed medications or prohibited medications must be cleared by the Medical Monitor prior to randomizing the subject.