Takeda Announces Positive Phase 3 Results for Oveporexton (TAK-861), the First-in-Class Oral OX2R Agonist for Narcolepsy Type 1

▎Armstrong

On July 14, 2025, Takeda announced positive data from two pivotal Phase III registrational clinical trials of Oveporexton (TAK-861), the world’s first OX2R agonist for the treatment of narcolepsy type 1 (NT1), achieving all primary and secondary endpoints.

These two Phase III clinical trials, FirstLight and RadiantLight, were conducted across 19 countries. After 12 weeks of treatment, both primary and secondary endpoints showed significant improvement, with p＜0.001. Takeda will expedite the submission of marketing applications to benefit patients with narcolepsy as soon as possible.

Takeda Predicts Oveporexton’s Sales Peak to Drop to $20-30 Billion.

Oveporexton is the world's first-in-class OX2R agonist, with the molecular structure shown in the figure below.

This year, MayIn the month, the Phase II clinical data of Oveporexton for the treatment of NT1 was published in the New England Journal of Medicine.The primary endpoint, compared with placebo, showed a significant increase in the mean sleep latency on the Maintenance of Wakefulness Test (MWT) across all dose groups.For key secondary endpoints, compared with placebo, all dose groups showed a significant decrease in Epworth Sleepiness Scale (ESS) scores and weekly cataplexy attack frequency (WCR), and this improvement persisted during the 8-week treatment period.

Summary

Takeda has multiple orexin-targeted projects, and the success of TAK-861 this time signifies clinical Proof of Concept (POC) for OX2R, with an anticipated annual sales peak of $2-3 billion.