By VETTAPHARMA reporter – Derek Roche: Takeda presented new Phase 3 data for oveporexton (TAK-861) at SLEEP 2026, demonstrating significant improvements in daily functioning, cognitive performance, and nighttime sleep among people with narcolepsy type 1 (NT1).
The findings build on previously reported pivotal efficacy results and further support the investigational orexin receptor 2 (OX2R)-selective agonist as a potential first-in-class disease-modifying therapy designed to address the underlying orexin deficiency that causes NT1.
The newly presented analyses included secondary and exploratory endpoints from the global Phase 3 FirstLight (TAK-861-3001) and RadiantLight (TAK-861-3002) studies. Across all evaluated doses, oveporexton significantly improved daily functioning compared with placebo at Week 12 (p<0.001) across all six domains of the Functional Impacts of Narcolepsy Instrument (FINI), including tiredness, cognitive functioning, cataplexy, social activities, everyday activities, and everyday responsibilities. Most treated participants achieved or exceeded published normative thresholds across these domains.
Oveporexton also demonstrated meaningful improvements in cognitive symptoms associated with NT1. Approximately 70% of patients receiving oveporexton across all dose groups reported no significant cognitive difficulties on the FINI Cognitive Function domain, compared with approximately 15% of patients receiving placebo. Improvements were also observed in objective neuropsychological assessments evaluating attention, executive function, and memory.
Exploratory analyses further showed improvements in nighttime sleep quality. Across both studies, most patients receiving oveporexton reported no hallucinations or sleep paralysis, while patients receiving the 2 mg twice-daily regimen experienced clinically meaningful reductions in disturbed nighttime sleep. The treatment also shifted the timing and pattern of rapid eye movement (REM) sleep toward that observed in healthy individuals.
The FDA previously accepted Takeda’s New Drug Application (NDA) for oveporexton and granted Priority Review, with a Prescription Drug User Fee Act (PDUFA) target action date expected in the third quarter of 2026. Regulatory submissions are also under review in China and Japan.
The FirstLight trial enrolled 168 participants randomized to twice-daily 2 mg, 1 mg, or placebo, while the RadiantLight study enrolled 105 participants randomized to 2 mg twice daily or placebo across 19 countries. More than 95% of participants completing the studies entered the ongoing long-term extension study.
Quick FAQs
1. What Is Oveporexton?
Oveporexton (TAK-861) is an investigational oral orexin receptor 2 (OX2R)-selective agonist designed to restore orexin signaling and address the underlying orexin deficiency responsible for narcolepsy type 1.
2. What Happened?
Takeda presented new secondary and exploratory Phase 3 data at SLEEP 2026 showing that oveporexton improved daily functioning, cognition, and nighttime sleep in patients with narcolepsy type 1.
3. What Are The FirstLight And RadiantLight Studies?
FirstLight (NCT06470828) and RadiantLight (NCT06505031) are global, multicenter, placebo-controlled Phase 3 studies evaluating the efficacy, safety, and tolerability of oveporexton over 12 weeks in patients with narcolepsy type 1.
4. What Is Narcolepsy Type 1?
Narcolepsy type 1 is a chronic neurological disorder caused by orexin deficiency, resulting in excessive daytime sleepiness, cataplexy, disrupted nighttime sleep, cognitive impairment, hallucinations, and sleep paralysis.
5. What Were The Key Results?
Oveporexton significantly improved daily functioning (p<0.001), reduced cognitive impairment, improved nighttime sleep, and increased the proportion of patients reporting no significant cognitive difficulties to approximately 70%, compared with approximately 15% for placebo.
6. Why Is This Important?
The findings demonstrate benefits across both daytime and nighttime manifestations of narcolepsy type 1, supporting oveporexton’s potential to become the first orexin agonist to address the underlying cause of the disease if approved.
