FDA Approves Orzeyful, First Drug Targeting Underlying Cause of Narcolepsy

The FDA approved oveporexton (Orzeyful) tablets for the treatment of narcolepsy type 1 (NT1) in adults, marking the first medicine indicated for the disorder as a complete condition rather than for isolated symptoms. The approval is also the first to work by directly targeting the loss of orexin signaling that underlies the disease.¹

“For too long, people with narcolepsy type 1 have had to manage a complex, lifelong neuropsychiatric condition with treatments that only address pieces of it,” Tiffany R. Farchione, MD, director of the Division of Psychiatry within the FDA’s Center for Drug Evaluation and Research, said in a news release.¹ “This new drug is the first medicine that impacts the underlying biology of the disease, treating narcolepsy type 1 as a whole.”

The approval was granted to Takeda Pharmaceuticals America Inc, which discovered and developed oveporexton, an oral orexin receptor 2 (OX2R) agonist. Oveporexton selectively stimulates OX2R to restore the signaling lost in NT1, addressing the underlying deficiency rather than masking symptoms with stimulants or sedatives.^1,2

What Causes NT1 and Why the Mechanism Matters

NT1 is a rare, lifelong neuropsychiatric sleep disorder caused by the loss of brain cells that produce orexin (also called hypocretin), a chemical messenger that regulates wakefulness, sleep, and muscle tone. Without orexin, the brain struggles to maintain alertness or control the boundary between sleep and waking, producing a cluster of disabling symptoms: excessive daytime sleepiness, cataplexy (sudden muscle weakness triggered by strong emotion), sleep paralysis, hallucinations at the edge of sleep, and disrupted nighttime sleep.¹

According to the Cleveland Clinic, narcolepsy type 1 is distinguished from type 2 specifically by the presence of cataplexy and, typically, very low orexin levels, and the loss of orexin-producing cells in the hypothalamus is believed to result from the immune system mistakenly attacking those cells. Existing pharmacologic options for narcolepsy span several drug classes—wake-promoting agents, stimulants, antidepressants, oxybates, and other agents that separately address sleepiness, cataplexy, or nighttime sleep disruption.³

Oveporexton is positioned as the first therapy to act on the disease mechanism directly rather than layering treatments across that symptom list.^1,2

Clinical Trial Results and Pharmacist-Relevant Safety Data

The FDA evaluated oveporexton’s effectiveness and safety in 2 randomized, double-blind, placebo-controlled 12-week studies enrolling 273 adults with NT1. Across both studies, patients taking oveporexton 2 mg showed improved ability to stay awake during the day compared with placebo, along with substantially less daytime sleepiness, a significant reduction in cataplexy episodes, and meaningful improvement across the full spectrum of NT1 symptoms, including sleep paralysis, hallucinations, and disrupted nighttime sleep.¹

Takeda's release identifies these as the global phase 3 FirstLight (TAK-861-3001; NCT06470828) and RadiantLight (TAK-861-3002; NCT06505031) studies, which also showed improvements in health-related quality of life.²

The most common adverse effects reported to the FDA were insomnia, increased urinary frequency, urgency to urinate, and increased saliva production, with a low rate of treatment discontinuation due to side effects. Takeda's pooled phase 3 safety data provide more granular figures: insomnia occurred in 60% of patients on the 2-mg twice-daily dose versus 1% on placebo; urinary frequency occurred in 58% versus 5%; and urinary urgency occurred in 16% versus 1%.²

Asymptomatic creatine phosphokinase elevations greater than 5 times the upper limit of normal were observed in 11% of Orzeyful-treated patients versus 5% on placebo, and pharmacists should counsel patients to report unexplained muscle pain, weakness, or dark urine.²

Orzeyful is contraindicated with strong CYP3A inhibitors, and pharmacists should note that concomitant use with strong or moderate CYP3A inhibitors increases oveporexton exposure, while strong and moderate CYP3A inducers can decrease its effectiveness.²

The drug should be avoided in patients with severe hepatic impairment (Child-Pugh C) or severe renal impairment on dialysis, as it has not been studied in those populations. Safety and effectiveness have not been established in patients younger than 18 years.^1,2

What Pharmacists Need to Know

Oveporexton has been recommended for scheduling under the Controlled Substances Act, and it will not be lawful to market until the DEA completes that scheduling decision. Takeda expects the DEA's controlled substance classification within 90 days of approval.^1,2

Once scheduling is finalized, oveporexton will be made available through a specialty pharmacy to US health care providers and adults living with NT1; patients and providers can sign up for availability updates through Orzeyful's website. Takeda also cautions that prescribing information is subject to change pending DEA scheduling and final label publication, meaning the safety and dosing details described here could still be revised before the drug reaches pharmacy shelves.²

The FDA noted that oveporexton received breakthrough therapy designation and priority review, designations reserved for therapies showing early evidence of substantial improvement over available treatments for serious conditions.¹

Takeda executives framed the approval as the start of a broader orexin therapeutic strategy: the company's pipeline includes additional oral orexin agonists, including TAK-360, under investigation for NT1, narcolepsy type 2, and idiopathic hypersomnia, as well as TAK-495.²

“For those of us living with narcolepsy type 1, symptoms reshape everyday life and extend far beyond what most people understand about the condition,” Julie Flygare, president and CEO at Project Sleep and a person with NT1, said in a news release.² “Orzeyful’s approval is a historic moment that expands our treatment choices and gives me great hope for the future and for our community.”

Emerging Evidence on Cognitive Symptoms

Separate from the phase 3 trials that supported this approval, a secondary analysis published in JAMA Neurology examined oveporexton's effects on cognition using data from an earlier, phase 2 trial (TAK-861-2001), an 8-week, placebo-controlled, dose-finding study in 112 adults with NT1.⁴

This cognition analysis is not part of the FDA's approved indication basis, but it may be clinically relevant background for pharmacists fielding patient questions, since cognitive symptoms are common in NT1. The study authors note that an estimated 80% to 90% of adults with NT1 report difficulty remembering, sustaining attention, and processing information, often despite treatment with currently available medications.⁴

In that phase 2 trial, 8 weeks of twice-daily oveporexton across 4 dose groups was associated with moderate to large improvements, relative to placebo, on standardized tests of attention (Psychomotor Vigilance Task), memory (Continuous Paired Associate Learning test), and executive function (One Back test and International Digit Symbol Substitution Test), compared with worsening or no change in the placebo group.⁴

The study authors concluded that these findings support orexin receptor 2 stimulation as a potential mechanism for improving cognitive symptoms in NT1, though they noted the trial was not designed to compare cognitive effects across doses and called for larger, more diverse study populations to confirm the findings.⁴

REFERENCES

1. Center for Drug Evaluation and Research. FDA approves first drug to treat the full range of narcolepsy type 1 symptoms. News release. FDA. August 5, 2026. Accessed August 6, 2026. https://www.fda.gov/news-events/press-announcements/fda-approves-first-drug-treat-full-range-narcolepsy-type-1-symptoms

2. Takeda Pharmaceutical Company Limited. U.S. FDA approves Takeda's ORZEYFUL™ (oveporexton), the first and only medicine to treat the underlying cause of narcolepsy type 1. News release. Takeda. August 5, 2026. Accessed August 6, 2026. https://www.takeda.com/newsroom/newsreleases/2026/orzeyful-approved-narcolepsy/

3. Cleveland Clinic. Narcolepsy. Cleveland Clinic. Last updated December 12, 2025. Accessed August 6, 2026. https://my.clevelandclinic.org/health/diseases/12147-narcolepsy

4. Lammers GJ, Plazzi G, Mignot E, et al. Effects of oveporexton, an orexin receptor 2–selective agonist, on cognition in narcolepsy type 1: a secondary analysis of a randomized clinical trial. JAMA Neurol. 2026;83(2):145-152. doi:10.1001/jamaneurol.2025.4825