Conditions: Attention Deficit Hyperactivity Disorder
Keywords: Inattention Hyperactivity Impulsivity Distractibility Procrastination Disorganized ADHD
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 740
Healthy volunteers: no

Brief summary:
This study tests the effects of an investigational antipsychotic drug (called OPC-34712) in adults with attention deficit hyperactivity disorder (ADHD) when taken with an approved stimulant medication to explore a possible impact on sleep, quality of life and cognitive function.

Detailed description:

Arms:
arm 1: Participants received single-blind matching-placebo tablets along with open-label stimulant determined by the investigator, once daily for 5 weeks. Once assigned to a stimulant by the investigator, participants remained on the same stimulant for the duration of the trial. Participants who met eligibility criteria i.e., who received prior treatment for adult ADHD and treatment-naïve participants were included in this arm group. Participants with incomplete response at the end of Phase A (Week 5) entered Phase B and rest of the participants continued to Phase A+. arm 2: Participants with incomplete response (with a \> 0% and \< 30% reduction in ADHD Symptoms Total Score {18 items} between the baseline of Phase A and the end of prospective treatment { Week 5} as measured by the CAARS-O:SV { Conners' Adult ADHD Rating Scale-Observer: Screening Version}, and a CAARS-O:SV ADHD Symptoms Total Score {18 items} of ≥ 24 at Week 5, and a clinical global impression - improvement scale (CGI-I) score of 3 or 4 at Week 5) at the end of Phase A (Week 5), received Brexpiprazole 2 milligram (mg) tablet along with stimulant determined by the investigator, once daily for 6 weeks (up to Week 11). arm 3: Participants with incomplete response (with a \> 0% and \< 30% reduction in ADHD Symptoms Total Score {18 items} between the Baseline of Phase A and the end of prospective treatment { Week 5} as measured by the CAARS-O:SV, and a CAARS-O:SV ADHD Symptoms Total Score {18 items} of ≥ 24 at Week 5, and a CGI-I score of 3 or 4 at Week 5) at the end of Phase A (Week 5), received matching-placebo tablets along with stimulant determined by the investigator, once daily for 6 weeks (up to Week 11). arm 4: Participants with response (with a ≥ 30% reduction in ADHD Symptoms Total Score {18 items} between Baseline of Phase A and the end of prospective treatment { Week 5} as measured by the CAARS-O:SV, or a CAARS-O:SV ADHD Symptoms Total Score {18 items} of \< 24 at Week 5, or a CGI-I score of \< 3 at Week 5) and non-response (with deterioration or no change in ADHD symptoms at Week 5) at the end of Phase A (Week 5), received single-blind matching-placebo tablets along with open-label stimulant determined by the investigator, once daily for an additional 6 weeks (up to Week 11).

Interventions: intervention 1: OPDC-34712 intervention 2: Placebo intervention 3: Stimulant Therapy
Intervention descriptions: intervention 1: OPDC-34712 tablets, daily, Orally. intervention 2: Matching-placebo tablets, daily, Orally. intervention 3: Mixed amphetamine salts or Dexmethylphenidate hydrochloride (HCL) or Methylphenidate HCl or Lisdexamfetamine dimesylate as per standard of care.

Protocol document: