The Food and Drug Administration (FDA) has rejected the supplemental New Drug Application (sNDA) for Hetlioz (tasimelteon; Vanda Pharmaceuticals) for the treatment of jet lag disorder.

Hetlioz, which is currently approved to treat non-24-hour sleep-wake disorder (Non-24), is an agonist at melatonin MT1 and MT2 receptors, which are thought to be involved in the control of circadian rhythms. The sNDA included data from the JET trial (N=25), a two-phase transatlantic travel study evaluating the effects of tasimelteon on jet lag disorder. 

Results showed tasimelteon significantly improved total sleep time in both objective and subjective measures of sleep, however in the complete response letter (CRL), the FDA took issue with how the Company measured sleep improvement, in which total sleep time over the 3 nights following transatlantic travel in untreated and treated patients was compared. In addition, the CRL included other observations that the Company intends to address with the FDA.

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“We are deeply disappointed to have not received approval at this time, given our previous discussions with the FDA on this program,” said Mihael H. Polymeropoulos, MD Vanda’s President and CEO. “Vanda remains committed to obtaining FDA marketing approval for tasimelteon in jet lag disorder in order to address this significant unmet medical need.”

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