FDA Clears Felix NeuroAI Wristband as First AI Wearable for Essential Tremor

The Food and Drug Administration has granted 510(k) clearance for the Felix NeuroAI Wristband (Fasikl, Minneapolis, MN), a novel transcutaneous peripheral nerve stimulation device to be used as a treatment for adults with essential tremor (ET). According to a statement from Fasikl, the clearance marks the first regulatory approval for a device of its kind for ET. The device uses software powered by artificial intelligence (AI) technology that incorporates patient movement and surface neural recordings to deliver tailored and dynamic electrical stimulation to the ulnar, median, and radial nerves.

The FDA decision was supported by positive results from the multicenter, sham-controlled TRANQUIL clinical trial (NCT06235190) conducted in 12 centers in China and the United States. This prospective, randomized, double-blind study included a total of 121 participants with a clinical diagnosis of ET who were randomized 2:1 to receive treatment with Felix NeuroAI or a sham device for home use over a period of 3 months. The primary end point was change from baseline in Tremor Research Group Essential Tremor Rating Scale (TETRAS) modified activities of daily living (mADL) score. These results were presented at the American Academy of Neurology (AAN) 2025 Annual Meeting. At 90 days:

• The primary end point was met: mADL scores improved by 6.9±6.0 points in the group wearing the Felix device vs 2.7±4.1 in the sham treatment group (P<.0001).
• Nearly two thirds (69.4%) of users of the Felix device were rated as improved on the Clinical Global Impressions of Improvement (CGI-I) scale vs 44.4% of sham users (P=.02).
• Use of the Felix device was also associated with improvements in quality of life (QoL) and psychosocial scores, significantly outperforming sham.
• The most common device-related adverse event (AE) was mild skin irritation, occurring in 34.9% of Felix users and 7% of sham users and leading to 2 discontinuations.

The company expects the device to be available through prescription in select regions in the United States in 2025 with full nationwide avilabililty expected in 2026. 

“For many patients, current treatment options fall short—pharmaceutical treatments are helpful for less than 50% of the patients, and deep brain stimulation and focused ultrasound, while effective, require surgical intervention,” said Rajesh Pahwa, MD, Laverne and Joyce Rider Professor of Neurology at the University of Kansas School of Medicine, Kansas City, KS. “This new AI wearable wristband backed by clinical evidence is an effective treatment option in patients with essential tremor.”