(RTTNews) - Vanda Pharmaceuticals Inc. (VNDA) announced positive topline results from its pivotal Phase 3 study of HETLIOZ (tasimelteon) in adults with Delayed Sleep-Wake Phase Disorder, a circadian rhythm disorder that causes people to fall asleep and wake much later than desired.
Delayed Sleep-Wake Phase Disorder (DSWPD), is more than simply being a "night owl." People with the disorder often cannot fall asleep until the early morning hours and may struggle to wake up for work, school, or other daily activities. The condition affects an estimated 0.2% to 1.5% of adults in the United States.
The Phase 3 trial was a multicenter, double-blind, randomized, placebo-controlled study evaluating once-daily oral HETLIOZ 20 mg for 28 days. Adults aged 18 to 75 years with a confirmed diagnosis of DSWPD received either tasimelteon or placebo.
According to the company, the study met its primary endpoint. Patients treated with HETLIOZ shifted the time of sleep onset 42.5 minutes earlier, compared with a 5.4-minute shift for placebo, resulting in a 37.1-minute treatment difference.
The company also reported that 60% of patients receiving HETLIOZ achieved a sleep onset shift of at least 30 minutes, compared with 15% of patients in the placebo group.
HETLIOZ is a circadian rhythm regulator that was first approved by the FDA in 2014 for Non-24-Hour Sleep-Wake Disorder in adults. In 2020, the drug received approval for nighttime sleep disturbances in people with Smith-Magenis Syndrome. If approved for DSWPD, it would become the first FDA-approved medicine specifically indicated for the condition.
HETLIOZ generated $5.6 million in net product sales during the second quarter of 2026, compared with approximately $16.5 million in the prior-year period, a 66% decline from year over year quarter. According to Vanda, the decline was partly due to the timing of shipment, with roughly $7.0 million in HETLIOZ revenue expected to be recognized in the third quarter of 2026.
Vanda said it intends to discuss the Phase 3 results with the FDA and submit a supplemental New Drug Application (sNDA) seeking approval of HETLIOZ for DSWPD. The company believes the new indication could expand the use of HETLIOZ into a third circadian sleep-wake disorder.
VNDA has traded between $4.27 and $9.94 over the past year. The stock closed Tuesday's trading at $5.03, down 2.71%. In overnight trading, the stock is at $5.54, up 10.14%.