A multicenter, open label, escalating dose study to assess the tolerability and the safety and to explore the efficacy and the pharmacokinetics of ND0801 in adult patients with attention deficit/hyperactivity disorder (ADHD).

Inclusion Criteria:

• Outpatients.
• Men and women 18-55 years of age.
• Primary DSM-IV diagnosis of adult ADHD confirmed by senior physician
• Capable and willing to provide informed consent
• Able to adhere to the treatment schedule, and withdrawal of ongoing pharmacotherapy for the treatment of ADHD prior to the beginning of the study treatment and during the study drug treatment.
• Subjects must be able to read, hear, write and speak the local language.
• Subject has signed a written informed consent to participate in the study.

Exclusion Criteria:

• Unstable or significant medical disorder.
• Current (within 12 months of baseline) primary or secondary depression.
• History of substance abuse or dependence within the past 6 months
• Any psychotic disorder (lifetime), including schizoaffective disorder, or major depression with psychotic features
• Bipolar disorder
• Eating disorder
• Obsessive compulsive disorder
• Post-traumatic stress disorder
• Current generalized anxiety disorder
• Presence of a personality disorder
• Individuals with a significant other neurological disorder.
• Use of any investigational drug within 4 weeks of the randomization visit
• Known or suspected pregnancy
• Women who are breast-feeding
• Women of childbearing potential and not using a medically accepted form of contraception