Clinical Research Directory

Inclusion Criteria: 1. Male and female subjects aged 6 to 12 years of age inclusive at time of consent 2. Meets DSM-5 criteria for ADHD, combined, hyperactive/impulsive or inattentive presentation using a clinical interview by an experienced clinician and confirmed with the Mini-International Neuropsychiatric Interview for children and adolescents (MINI-KID) 3. Meets DSM-5 criteria for Oppositional Defiant Disorder confirmed with the MINI-KID 4. The subject has a parent or legal guardian who will give written informed consent for the subject to participate in the study 5. Subject and parent/legal guardian must be able to speak, read, write, and understand English 6. Subject and parent/legal guardian must agree to comply with all protocol requirements 7. ADHD-RS-5 score of ≥28 at Screening and Baseline if not taking ADHD medications. If taking ADHD medication, must have ADHD-RS-5 score of ≥28 after washout at Baseline 8. Subject has a CGI-S score of ≥4 at Screening if not taking ADHD medication. If taking ADHD medication must have CGI-S score of ≥4 at Baseline 9. Subject must live with primary caretaker/rater 10. Sitting systolic and diastolic blood pressure below the 95th percentile for age, gender, and height 11. Subject is functioning at age-appropriate level intellectually based on investigator's opinion 12. If a female has experienced menarche, she must have a negative serum beta human chorionic gonadotropin (hCG) pregnancy test at Screening, a negative urine pregnancy test at Baseline, and agree to be abstinent from sexual activity that could result in pregnancy, or use acceptable contraceptives throughout the entire study 13. Must be able to discontinue stimulants 7 days prior to Baseline and nonstimulants 14 days prior to Baseline Exclusion Criteria: 1. Subject has a current severe comorbid psychiatric condition (except oppositional defiant disorder \[ODD\]) that is controlled (requiring a prohibited medication or behavioral modification program) or uncontrolled. These conditions include comorbid disorders, such as bipolar illness, psychosis, autism spectrum disorder, post-traumatic stress disorder, obsessive-compulsive disorder, substance use disorder, or conduct disorder, that in the opinion of the Investigator, contraindicate treatment with OnydaTM XR, or confound efficacy or safety assessments 2. Use of another investigational drug in the 30 days prior to screening 3. Use of anticonvulsants, antidepressants, or antipsychotics in the 30 days prior to screening 4. History (in the past 12 months) or presence of clinically significant cardiovascular, cerebrovascular, renal, hepatic, gastrointestinal, pulmonary, immunological, hematological, endocrine, or neurological disease, that in the opinion of the investigator, could put the subject at risk if he/she participates in the trial, or confound study results 5. History of presence of suicidal ideation or self-injurious behavior 6. Subject has orthostatic hypotension or history of hypertension 7. Subject has clinically significant ECG findings as judged by the investigator. 8. Subject has a QTc-Fridericia (QTc-F) \> 450 ms in males or \> 470 ms in females at screening 9. Subject has participated in another clinical trial within 30 days prior to screening 10. Subject has an allergy or intolerance to clonidine or OnydaTM XR 11. Subject has clinically significant abnormal laboratory values at screening 12. Subject has a positive drug screen at Screening, except for ADHD medications with a valid prescription 13. Subject has a positive drug screen at Baseline 14. Subject is currently considered a suicide risk, has previously made a suicide attempt, or has active suicidal ideation based on the Columbia Suicide Severity Rating Scale. Specifically, any positive response on C-SSRS items 4 or 5 currently at screening, or in the past 12 months, is exclusionary 15. Subject has a history of a seizure disorder, except for children who have had febrile seizures prior to age 5 years 16. Subjects who have been treated with clonidine or guanfacine in the past 30 days 17. History of failure to respond to clonidine or guanfacine 18. Subject started psychotherapy less than 30 days prior to screening \-