FDA Approves Vanda for Rare Sleep Disorder

FDA has approved a Vanda Pharmaceuticals NDA for Hetlioz (tasimelteon) capsule and liquid formulations for treating adults and children with nighttime sleep disturbances associated with Smith-Magenis Syndrome (SMS). The rare neurodevelopmental disorder, which involves an “inverted” circadian rhythm, makes it extremely difficult for patients with SMS to sleep during the night, the company says. Hetlioz (tasimelteon) is a melatonin receptor agonist.

Vanda says SMS is caused by a small deletion of human chromosome 17p, and in more rare cases it is caused by a point mutation in the RAI1 gene which resides in the deleted region. It is estimated to affect 1/15,000-25,000 births in the U.S. “Patients with SMS present with a number of physical, mental and behavioral problems,” it says, adding that the most common symptom of SMS is a severe sleep disorder.