FDA Grants Priority Review to Takeda's Oveporexton, the First Orexin Agonist to Reach the Doorstep of Approval for Narcolepsy Type 1
Takeda's oveporexton, an oral drug that restores the brain chemical missing in narcolepsy type 1, has received FDA priority review after two Phase 3 trials showed it brought patients to near-normal wakefulness and cut cataplexy episodes by more than 80 percent.
Overview
The U.S. Food and Drug Administration accepted Takeda Pharmaceutical’s New Drug Application for oveporexton and granted it priority review on February 10, 2026, placing the drug on track for a decision in the third quarter of this year, according to Takeda via BusinessWire. If approved, oveporexton would become the first orexin receptor agonist cleared for any indication, and the first therapy to directly target the neurochemical deficiency that causes narcolepsy type 1.
The drug also holds Breakthrough Therapy designation from the FDA for excessive daytime sleepiness in narcolepsy type 1, as well as Sakigake designation from Japan’s Ministry of Health, Labour and Welfare, underscoring the international consensus that it addresses a serious unmet need.
The Biology of Narcolepsy Type 1
Narcolepsy type 1 is a chronic neurological disorder caused by the destruction of hypothalamic neurons that produce orexin, a neuropeptide essential for maintaining stable wakefulness and suppressing inappropriate transitions into REM sleep. More than 90 percent of patients with narcolepsy type 1 have cerebrospinal fluid orexin levels below 110 picograms per milliliter, effectively near zero. The resulting orexin deficit produces excessive daytime sleepiness, cataplexy (sudden loss of muscle tone triggered by emotion), fragmented nighttime sleep, and hallucinations at sleep onset.
Existing treatments manage symptoms without addressing the underlying cause. Modafinil and armodafinil promote wakefulness through dopaminergic mechanisms. Sodium oxybate consolidates nighttime sleep and reduces cataplexy but carries a Risk Evaluation and Mitigation Strategy due to abuse potential. None of these drugs restore the orexin signaling that narcolepsy type 1 patients lack.
Phase 3 Trial Results
Takeda’s NDA submission rests on two pivotal Phase 3 trials, FirstLight and RadiantLight, which together enrolled 273 patients with narcolepsy type 1 across 19 countries, according to Takeda via BusinessWire. FirstLight randomized 168 participants to high-dose, low-dose, or placebo arms, while RadiantLight enrolled 105 participants across high-dose and placebo groups. Both trials ran for 12 weeks.
All primary and secondary endpoints were met with p-values below 0.001. On the Maintenance of Wakefulness Test, the standard objective measure of ability to stay awake, patients on the higher dose achieved increases of 20 and 17 minutes over placebo in the two trials respectively, reaching the normative wakefulness range of 20 minutes or greater, according to STAT News. Approximately 85 percent of treated participants achieved Epworth Sleepiness Scale scores of 10 or below, the threshold considered comparable to healthy individuals.
Cataplexy outcomes were equally striking. Median weekly cataplexy rates fell by more than 80 percent from baseline across all dose groups, and median cataplexy-free days per week improved from zero at baseline to four to five days by week 12, according to BioPharma Dive. No serious treatment-related adverse events were reported, and more than 95 percent of participants enrolled in the ongoing long-term extension studies, suggesting both tolerability and patient willingness to continue treatment.
The most common adverse events were insomnia, urinary urgency, and urinary frequency, all generally mild to moderate in severity. Notably, the trials found no evidence of liver toxicity or visual disturbances, two safety concerns that had shadowed the broader orexin agonist drug class, according to BioPharma Dive.
A Competitive Race
Takeda is not alone in pursuing orexin-based therapeutics. Alkermes has advanced its own orexin agonist, alixorexton, into late-stage testing after positive Phase 2 data presented at the World Sleep Congress in September 2025 showed it also helped narcolepsy patients reach normal levels of wakefulness, according to STAT News. Centessa Pharmaceuticals is developing ORX750, another oral orexin agonist candidate. The convergence of multiple programs validates the mechanistic thesis but raises the prospect of a crowded market should multiple drugs reach approval.
Takeda holds a significant timing advantage. With an NDA already accepted and priority review granted, oveporexton could reach market well before competitors complete their Phase 3 programs. The company is also developing TAK-360, a next-generation OX2R agonist, for narcolepsy type 2 and idiopathic hypersomnia, conditions that oveporexton’s current trials did not address.
What Approval Would Mean
Narcolepsy type 1 affects an estimated 25 to 50 people per 100,000 in the United States, but diagnosis is often delayed by years because symptoms overlap with other sleep and psychiatric disorders. Current treatments can reduce symptoms but do not restore normal sleep-wake architecture. An orexin agonist that replaces the missing signal would represent a fundamentally different therapeutic approach, akin to insulin replacement in type 1 diabetes.
Andy Plump, President of Research and Development at Takeda, called the FDA’s acceptance “a milestone for people living with narcolepsy type 1,” according to Takeda via BusinessWire. The PDUFA decision is expected in the third quarter of 2026.