The first medical device to treat attention deficit-hyperactivity disorder (ADHD) in children Friday.
The prescription-only device from , called the Monarch external Trigeminal Nerve Stimulation (eTNS) system, delivers low-level electrical stimulation to branches of the trigeminal nerve, sending signals to parts of the brain thought to be involved in ADHD. The pocket-sized device is designed to be used externally at night and is indicated for children aged 7-12 currently not taking prescription ADHD medication.
The FDA's decision -- technically, to permit marketing under the agency's premarket review pathway -- marks the first non-drug treatment for ADHD to get the agency's OK.
"This new device offers a safe, non-drug option for treatment of ADHD in pediatric patients through the use of mild nerve stimulation, a first of its kind," Carlos Peña, PhD, director of the Division of Neurological and Physical Medicine Devices of the FDA's Center for Devices and Radiological Health, said in a statement.
Its efficacy in treating ADHD was reported in a in which 62 children with moderate to severe ADHD used either the eTNS therapy each night (n=32) or a placebo device (n=30) at home for 4 weeks. The trial's primary endpoint was improvement on a clinician-administered ADHD Rating Scale (ADHD-RS), a measurement of severity and frequency of ADHD symptoms in which higher scores represent worsening symptoms. After 4 weeks, the average ADHD-RS score in the active group decreased from 34.1 points at baseline to 23.4 points, while the placebo device group experienced a decrease from 33.7 to 27.5 points.
Response patterns suggested the greatest degree of improvement in the eTNS group occurred during the first week, with additional improvements accruing with ongoing use. "The week 4 is within the same range typically evidenced with non-stimulant ADHD medications," wrote James McGough, MD, of the University of California Los Angeles, and colleagues, in the Journal of American Academy of Child and Adolescent Psychiatry.
It's not known exactly how the nerve stimulation relieves ADHD symptoms, but imaging studies have shown eTNS boosts activity in the brain regions known to be important in regulating attention, emotion, and behavior.
The most common side effects observed with eTNS were drowsiness, increased appetite, trouble sleeping, teeth clenching, headache, and fatigue. No serious adverse events were linked to the device. In the clinical trial, children experienced pulse increases which were statistically significant, but not within a clinically abnormal range and not associated with clinical symptoms. Increases in reported appetite in children who received eTNS have not been explained and require investigation in longer studies, McGough and co-authors noted.
The Monarch eTNS System should not be used in children under 7 years of age, or in patients with an active implantable pacemaker, active implantable neurostimulator, or body-worn device such as an insulin pump, the FDA said. It also should not be used in the presence of radio frequency energy such as MRI or even cellular phones; the latter's low-level radiation may interrupt the therapy.
The FDA reviewed the Monarch eTNS System through the de novo premarket review pathway for novel low- to moderate-risk devices. It can now serve as a so-called predicate device in 510(k) applications for future devices with similar activity.