NeuroSigma has received US Food and Drug Administration (FDA) approval for its second-generation Monarch external trigeminal nerve stimulation (eTNS) system to treat pediatric attention deficit hyperactivity disorder (ADHD). Monarch eTNS 2.0 works by delivering mild electrical impulses to the trigeminal nerve, a major cranial nerve involved in various sensory functions. The device is designed to provide an alternative treatment for children aged seven to 12 who are not using prescription medications to treat their ADHD. NeuroSigma is finalizing enrolment of subjects in two double-blind, multicentre trials across the US and the UK in H2 2024. The Phase I ADHD-GEMS trial will enroll 225 children between UCLA and Seattle Children’s Hospital. The Phase II trial, sponsored by the UK’s National Institute for Health Research and named the ATTENS project, will enroll up to 150 children.