Open-label Study to Evaluate Long-term Safety and Efficacy of SPN-812 Extended Release (ER)

This is a multicenter, open-label extension study aimed to assess long-term safety and
efficacy of SPN-812 ER when administered alone or in conjunction with an Food and Drug
Administration-approved Attention Deficit Hyperactivity Disorder (ADHD) medication in the
treatment of ADHD in pediatric subjects who have participated in a previous blinded studies
of SPN-812 ER (812P202, 812P301, 812P302, 812P303, and 812P304). All pediatric subjects who
complete a blinded study of SPN-812 ER will have the option to participate in this study in
which all subjects receive SPN-812 ER at an optimized dose. After an initial dose, subjects
will enter an dose optimization phase of up to twelve weeks. Following optimization, subjects
will return to the clinic every 3 months or until the subject discontinues or the study ends
at 36 months.

Inclusion Criteria:

1. Completion of a previous blinded study of SPN-812 ER for the treatment of ADHD.

2. Continues to be medically healthy and with clinically normal laboratory profiles,
vital signs, and electrocardiograms.

3. Weight of at least 20 kg.

4. Written Informed Consent obtained from the subject's parent or legally authorized
representative; written Informed Assent obtained from the subject if appropriate.

Exclusion Criteria:

1. Diagnosis of major depressive disorder, bipolar disorder, personality disorder,
Tourette's disorder, or psychosis not otherwise specified.

2. Currently meeting Diagnostic and Statistical Manual of Mental Disorders-5 criteria for
an anxiety disorder as primary diagnosis.

3. Current evidence of suicidality (suicidal thoughts or behaviors).

4. Body Mass Index greater than 95th percentile for the appropriate age and gender.

5. Pregnancy, or refusal to practice contraception during the study (for female subjects
of childbearing potential).

6. Current substance or alcohol use.

7. Any reason which, in the opinion of the Investigator, would prevent the subject from
participating in the study.