Vanda Pharmaceuticals Inc. said the U.S. Food and Drug Administration rejected the marketing application for its drug Hetlioz to treat patients with jet lag disorder.
The application was based on jet lag simulation studies that took patients on a transatlantic trip. Participants of the studies reported sleeping about three hours longer in three nights following their trip when taking Hetlioz compared to when they were untreated.
In its complete response letter, the FDA noted that the measures demonstrating improved sleep were of unclear clinical significance. Vanda plans to work with the U.S. regulator on all observations regarding its application.
Vanda CEO Mihael Polymeropoulos said the company "remains committed to obtaining FDA marketing approval for tasimelteon in jet lag disorder in order to address this significant unmet medical need."
Hetlioz is already approved for treating non-24-hour sleep-wake disorder, which disturbs the body clock in those who are blind and causes problems with sleep timings.
The Washington, D.C.-based biotechnology company is also developing the drug for a rare sleep condition. Hetlioz, or tasimelteon, improved the overall total nighttime sleep duration by an average of about 41 minutes per night along with sleep quality in 25 patients with a disorder known as Smith-Magenis syndrome, or SMS, during a phase 2 study.
SMS is caused by the deletion of a human chromosome, resulting in various physical, mental and behavioral problems. The most common symptom of SMS is a severe sleep disorder.
