This is a randomized, double-blind (DB), placebo-controlled, parallel, study to assess the efficacy and safety of AMPH ER TAB compared to placebo for the treatment of ADHD in adults aged 18 to 60 years.~After Screening and Baseline evaluations are complete, eligible subjects will be randomized in the study to take DB AMPH ER TAB or matching placebo orally once daily in the morning beginning the day after the Baseline visit for 5 weeks. Dose will be titrated on a weekly basis to reach 20 mg per day.Subjects who cannot tolerate the study drug will be discontinued from the study.~A Math Test placement test will be done at Screening or at Baseline. At Visit 5, efficacy assessments will include the administration of serial Math Tests at pre-dose and at 0.5, 1, 2, 4, 8, 10, 12, 13, and 14 hours post-dose.~Adult Investigator Symptom Rating Scale (AISRS) and Clinical Global Impression Scale Severity (CGI-S) will be conducted at Baseline and Visits 1 to 5. Digit Symbol Substitution Test (DSST) will be administered at Baseline and Visit 5.~Safety assessments will include treatment-emergent adverse events, physical examination, vital signs, body weight, Columbia Suicide Severity Rating Scale (C-SSRS), and direct questioning to assess for sleep, appetite, mood and psychotic events.
To evaluate the efficacy of AMPH ER TAB compared to placebo in adult patients with ADHD aged 18 to 60 years.