Exploratory fMRI Study on the Treatment for Impulsive Aggression in Children With ADHD

Exploratory Neuroimaging Study to Evaluate the Effect on Brain Activity of SPN-810 for Impulsive Aggression (IA) in Patients With Attention-Deficit/Hyperactivity Disorder (ADHD) in Conjunction With Standard ADHD Treatment

The purpose of this study was to evaluate the effect of 4-week SPN-810 treatment on brain functioning in patients aged 8-12 years with ADHD and associated feature of impulsive aggression (IA). This was achieved using functional magnetic resonance imaging (fMRI) in conjunction with the point subtraction aggression paradigm (PSAP) Task, a behavioral aggression paradigm in which subjects are provoked by having money indirectly taken from them by a fictitious opponent, simulating an aggression response.

Approximately 30 subjects aged 8-12 diagnosed with ADHD and associated feature of IA were recruited in this study. The PSAP is a behavioral aggression test used to evaluate behavioral response related to impulsive aggression. The task was combined with functional MRI to evaluate the change in brain activity measured as BOLD signal (blood oxygenation level-dependent) from baseline to the end of the treatment with SPN-810.

The level of neurotransmitters Glutamate and GABA were also measured using magnetic resonance spectroscopy (MRS).

Additionally, the improvement and severity in impulsive aggression behaviors were assessed using validated scales.

Inclusion Criteria:

• Otherwise healthy male or female subjects, aged 8-12 years, inclusive, at the time of screening with primary diagnosis of ADHD and currently receiving monotherapy treatment with an optimized US Food and Drug Administration (FDA)-approved ADHD medication.
• Impulsive aggression (IA) confirmed at screening using the R-MOAS and the Vitiello Aggression Scale.

Exclusion Criteria:

• Current or lifetime diagnosis of epilepsy, major depressive disorder, bipolar disorder, schizophrenia or related disorder, personality disorder, Tourette's disorder, fetal alcohol syndrome, or psychosis not otherwise specified.
• Currently meeting DSM criteria for autism spectrum disorder, pervasive developmental disorder, obsessive-compulsive disorder, post-traumatic stress disorder.
• Known or suspected IQ <70, pregnancy, substance or alcohol abuse.
• Known history of implanted brain stimulator, vagal nerve stimulator, ventriculoperitoneal shunt, cardiac pacemaker, orthodontic braces, or implanted medication port. Visual and hearing (≥25 dB) impairment.
• Pre-existing medical or psychological conditions that preclude being in the MRI scanner (e.g., claustrophobia, morbid obesity, or marked anxiety about the procedure).