Oveporexton for narcolepsy
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What is oveporexton for narcolepsy?
Oveporexton, also known as TAK-861, is an oral therapy being developed to treat type 1 narcolepsy.
Narcolepsy is a neurological condition in which the brain can’t regulate sleep-wake cycles, leading to excessive daytime sleepiness, episodes of sudden muscle weakness (cataplexy), and other symptoms related to the intrusion of sleep into waking hours.
For people with type 1 narcolepsy, the disease is driven by a loss of nerve cells that produce orexin, a brain signaling chemical that stabilizes sleep-wake cycles and promotes alertness.
Oveporexton is designed to mimic orexin’s effects in the body, replacing the wake-promoting actions of the missing chemical. It does this by binding to and activating the receptor proteins through which orexin normally exerts its effects.
The therapy is being developed by Takeda Pharmaceuticals. It is now being reviewed by U.S. regulators, and a decision on its potential approval for people with narcolepsy is expected later this year. Similar applications have also been submitted in China and Japan.
The medication was granted breakthrough therapy designation in the U.S. for treating excessive daytime sleepiness in people with narcolepsy type 1. That status is intended to expedite its clinical development and regulatory review.
Therapy snapshot
| Treatment name | Oveporexton |
| Administration | Oral tablets |
| Clinical testing | Phase 3 testing completed; under regulatory review in the U.S. |
How will oveporexton be administered in narcolepsy?
In Phase 3 clinical trials involving people with narcolepsy, oveporexton was administered in the form of oral tablets, taken twice daily, at a dose of 1 or 2 mg.
Oveporexton in narcolepsy clinical trials
Takeda’s regulatory applications seeking oveporexton’s approvals were largely supported by data from two global Phase 3 clinical trials: FirstLight (NCT06470828) and RadiantLight (NCT06505031). Together the studies involved 273 people, ages 16-70, with type 1 narcolepsy.
In either trial, participants received either oveporexton or a placebo twice daily for about three months. FirstLight tested two different doses of oveporexton while RadiantLight tested only one.
Takeda reported that both trials met all of their primary and secondary endpoints, or goals. Relative to the placebo group, either dose of oveporexton:
- improved objective and subjective measures of daytime alertness, with many participants achieving scores comparable to those of healthy people
- reduced weekly cataplexy rates and increased the median number of cataplexy-free days
- eased the patient-reported overall symptom severity, with nearly all treated participants reporting an improvement
- improved quality of life
After the main studies, most participants entered a long-term extension study (NCT05816382), in which all are receiving oveporexton.
Oveporexton side effects
In Phase 3 trials testing oveporexton in people with narcolepsy, the most commonly reported side effects were:
- insomnia
- needing to urinate more often and more urgently than usual
Most side effects were mild or moderate. No serious treatment-related side effects were observed, according to Takeda.
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