ADHD is a neurodevelopmental disorder. It is the most common neurodevelopmental disorder in children and adolescents. Its prevalence is estimated at 5.9% in this population. The symptoms of ADHD combine attention deficit with behavioural disorders such as hyperactivity and impulsivity. Current treatment for ADHD is based on psychotherapeutic and psychoeducational measures aimed at improving behaviour and its impact on the family, social and school environment. Drug treatments may also be used, depending on the impact of the disorder and the effectiveness of alternative treatments. Psychostimulants such as amphetamine derivatives and methylphenidate are around 80% effective.

Sulforaphane is an active substance derived from broccoli that has already been tested in the treatment of other neurodevelopmental disorders. The main hypothesis is that sulforaphane is effective in treating the symptoms of Attention Deficit Disorder with or without Hyperactivity (ADHD) in children.

This is a randomised controlled trial with a double-blind control group. The aim is to test the efficacy of Sulforaphane versus placebo by comparing these two groups with a 1:1 ratio.

The primary objective is to evaluate the efficacy of sulforaphane treatment versus placebo on the total inattention and hyperactivity/impulsivity score measured by the ADHD-RS scale (parents) at 8 weeks in children aged 6 to 12 years suffering from ADHD.

The primary endpoint was the ADHD-RS parent inattention and hyperactivity/impulsivity score at 8 weeks.

Secondary objectives:

To assess the efficacy of sulforaphane treatment versus placebo at 2, 4 and 8 weeks in children aged 6-12 years with ADHD on:

• Inattention and hyperactivity/impulsivity symptoms assessed by parents using the ADHD-RS;
• Social interactions using the SRS scale (Social Responsiveness Scale);
• Emotional dysregulation using the SDQ (Strength and Difficulties Questionnaire);
• Global functioning using the CGI-S (Clinical Global Impression - Severity) and the CGI-I (Clinical Global Impression - Improvement).

To assess the effect of treatment with sulforaphane versus placebo on attention and inhibition at 4 and 8 weeks: using a specific neuropsychological assessment: CPT (Continuous Performance Test); symptoms of inattention and hyperactivity/impulsivity assessed by the teacher using the ADHD-RS self-questionnaire. Differences in behaviour may be observed depending on the context (school versus family). It is therefore important to have 2 sources of information for the ADHD-RS questionnaire: the parents and the teacher.

To assess the tolerability of treatment with sulforaphane from a clinical point of view (use of a PAERS (Paediatrician Adverse Events Rating Scale) and a biological point of view (blood count, AST, ALT, total and conjugated bilirubin, blood ionogram, urea, creatininemia, T4, TSH).

The subgroup of patients included in the Robert Debré Hospital will have a High Resolution Electroencephalogram (HR-EEG) in order to study the electroencephalographic markers of response to treatment with sulforaphane.

An interview to assess interest in and satisfaction with the treatment will be conducted with the parents (Robert Debré) and the child in the month following the end of the study as part of a qualitative study.

Inclusion Criteria:

• Children aged 6 to 12
• Diagnosis of ADHD according to DSM-5 criteria (Diagnostic and Statistical Manual of Mental Disorders)
• Followed or hospitalised in an investigating centre
• Consent of holders of parental authority
• Patient covered by health insurance (social security or CMU)
• Patients able to swallow capsules

Exclusion Criteria:

• Allergy to broccoli
• Psychotropic treatment including methylphenidate in the month prior to inclusion
• Ongoing psychotherapeutic and/or psycho-educational treatment specific to ADHD
• ASD (Autism Spectrum Disorder) according to DSM-5 criteria, intellectual disability (IQ< 80)
• Chronic neurological disease, epilepsy
• Holders of parental authority under guardianship or curatorship
• Previous intake of sulforaphane
• Known hypothyroidism or current thyroid treatment
• Participation in other interventional research involving the human person or being within the exclusion period following previous research involving the human person, where applicable
• Patient under AME (state medical aid)

placebo