Complete Response Letter for Hetlioz for the treatment of Jet Lag Disorder

Vanda Pharmaceuticals Inc. announced that on 16 August 2019, it received a Complete Response Letter (CRL) from the FDA as part of its ongoing review of Vanda's supplemental New Drug Application (sNDA) for Hetlioz (tasimelteon) for the treatment of Jet Lag Disorder (JLD). As Vanda previously reported on 23 May 2018, JLD patients reported sleeping nearly three hours longer over the three nights following their transatlantic trip when treated with Hetlioz than they did over the three nights following their untreated transatlantic trip, consistent with Vanda's jet lag simulation studies.

In the CRL, the FDA asserted that these measures demonstrating improved sleep are of unclear clinical significance. Vanda is perplexed by this conclusion, given that millions of travelers who experience JLD every year recognize that JLD is characterized by disruption of nighttime sleep and/or sleepiness during the day due to rapid travel across time zones. Consistent with this, the American Academy of Sleep Medicine lists disturbed sleep and daytime sleepiness as essential features of Jet Lag Disorder (International Classification of Sleep Disorders, 3rd Edition, 2011).

JLD sufferers attempt to treat the condition with unapproved remedies, which do not address either the symptoms or the underlying cause of JLD. Additionally, these treatments are replete with potentially dangerous side effects when used. To date, there are no treatments approved by the FDA for JLD, a public health issue experienced by millions of people every year.

The FDA's conclusions regarding the clinical significance of improved sleep in JLD are not the FDA's only observations made with respect to the sNDA. The CRL contains additional observations on various aspects of Vanda's sNDA. Vanda intends to consider each observation as it plans for continued engagement with the FDA on this matter.