Pharmacokinetic Study of Methylphenidate HCl Extended-Release Capsules in Children 4 to Under 6 Years of Age With ADHD

This will be a multi-center, open-label, single-dose, study to assess the pharmacokinetics
of Aptensio XR® (methylphenidate hydrochloride extended-release) capsules in male and female
children 4 to under 6 years of age with ADHD in fed condition.

Screening Procedures: After obtaining written informed consent from parents, subjects will
undergo a complete medical and medication history, demographic data (including sex, age,
race, ethnicity, body weight (kg), height (cm), Body Mass Index (BMI) (kg/m2), physical
examination, vital signs evaluation (sitting blood pressure, pulse rate, respiration rate,
temperature and pulse oximetry), resting 12-lead electrocardiogram (ECG), clinical
laboratory tests and concomitant medication within 28 days prior to receiving study drug. On
Day 1: subjects will receive a single oral dose of Aptensio XR®.

Inclusion Criteria:

1. Patient is a male or female between the ages of 4 and under 6 years old.

2. Patient has a history consistent with ADHD, meets the DSM-IV criteria for ADHD,
inattentive, hyperactivity or combined.

3. Patient must meet criteria for ADHD diagnosis on KSADS-PL and clinical interview by
experienced clinician; symptoms must have been present for at least 6 months.

4. Subject has had prior behavioral treatment or subject's symptoms are severe enough to
warrant treatment without prior behavioral treatment, and patient is on a stable dose
of either immediate-release or extended-release methylphenidate.

5. Subject must have age- and sex-adjusted ratings of ≥ 90th percentile Total Score on
the ADHD-RS-IV Preschool Version, a Clinical Global Impressions -Severity Score of ≥4
and a Child Global Assessment Scale rating of <65 after methylphenidate washout and
prior to obtaining pharmacokinetic samples. Ratings may be completed via telephone on
day-1.

6. Parents or guardians of patients must have the ability to read and understand the
language in which the Informed Consent is written and are mentally and physically
competent to provide written informed consents for their child.

7. Patient and/or parent are/is able to understand English in order to provide assent
and is otherwise able to comply with the study protocol.

Exclusion Criteria:

1. Patient has allergy to methylphenidate or amphetamines, or history of serious adverse
reaction to methylphenidate.

2. Patient has a history of tension, agitation, glaucoma, thyrotoxicosis,
tachyarrythmias or severe angina pectoris or patient with serious or unstable medical
illness such as asthma, diabetes or seizures.

3. A history of motor or vocal tics or Tourette's syndrome

4. Patient is receiving MAO inhibitors, anticonvulsants (phenobarbital, phenytoin,
primidone), coumarin anticoagulants, presser agents, guanethidine, tricyclic
antidepressants (imipramine, desipramine, selective serotonin inhibitors (SSRIs), or
herbal remedies (e.g., melatonin).

5. Patient has serious hypertension.

6. Patient has a history of disorders of the sensory organs, particularly deafness,
severe or profound retardation.

7. Patient has any other unstable psychiatric condition requiring treatment.

8. Patient is at risk for substance abuse.

9. Evidence of current physical, sexual, or emotional abuse

10. Living with anyone who currently abuses stimulants or cocaine

11. History of bipolar disorder in both biological parents