Vanda Pharmaceuticals reported positive topline results from a pivotal Phase III study of HETLIOZ (tasimelteon) 20 mg in adults with Delayed Sleep-Wake Phase Disorder (DSWPD), a circadian rhythm disorder in which the body clock is persistently delayed. The study met its primary endpoint: sleep onset occurred 42.5 minutes earlier with tasimelteon versus 5.4 minutes earlier with placebo, a 37.1-minute difference (p=0.022). In an exploratory analysis, 60% of treated participants advanced sleep onset by at least 30 minutes, compared with 15% of placebo recipients (p=0.008). Vanda plans to discuss the findings with the FDA and submit a supplemental New Drug Application, or sNDA, seeking a DSWPD indication. If approved, HETLIOZ would be the first FDA-approved medicine for the condition. Safety during the 28-day controlled period was consistent with the established label, with no new safety signals identified. Vanda shares rose 3.98% to $5.23 in premarket trading on Wednesday, according to Benzinga Pro data.