ORZEYFUL approved in Japan as the first and only medicine to address the underlying cause of narcolepsy type 1

ORZEYFUL has the potential to move care beyond individual symptom management for adults living with narcolepsy type 1.

Landmark Phase 3 studies showed significant and meaningful improvements across the full range of narcolepsy type 1 symptoms measured in clinical trials, compared with placebo.

Takeda announced that Japan’s Ministry of Health, Labour and Welfare has approved ORZEYFUL (oveporexton) for treating narcolepsy type 1, also known as narcolepsy with cataplexy, in adults. ORZEYFUL is a first-in-class oral orexin receptor 2 agonist and stands as the only medicine approved in Japan to treat the disease as a whole rather than targeting individual symptoms. This new class of medicine was discovered in Takeda’s own laboratories in Japan, and the company is now preparing for launch, aiming to make ORZEYFUL available to patients as soon as possible.

Julie Kim, president and chief executive officer of Takeda, said the discovery of the first orexin agonist represents a successful example of science originating in Japan that will have a direct impact on people living with narcolepsy type 1 around the world. She said ORZEYFUL has the potential to reshape how narcolepsy type 1 is treated and serves as the first proof point for the company’s broader orexin strategy, showing how scientific innovation can open new possibilities for patients while driving future growth for Takeda.

Narcolepsy type 1 is a chronic, rare neurological condition caused by a deficiency of orexin. Those affected experience a range of symptoms both day and night, including excessive daytime sleepiness, cataplexy (sudden loss of muscle tone), disrupted sleep at night, sleep paralysis, hallucinations, and cognitive difficulties. Because the condition affects patients around the clock, it can significantly disrupt work, education, and social life. Despite this substantial impact, limited awareness of the disease and the complexity of its symptoms often lead to misdiagnosis, with an average delay of more than ten years before patients receive an accurate diagnosis.

Yuichi Inoue, professor in the Department of Somnology at Tokyo Medical University, said narcolepsy type 1 can affect patients’ lives around the clock, and that treatment has traditionally focused on managing individual symptoms rather than the condition as a whole. He said recent progress in understanding the underlying biology of narcolepsy has opened the door to new therapeutic approaches, and that he looks forward to seeing a wider range of treatment options become available so physicians can tailor care to each patient’s individual needs.

The approval rests on a broad clinical program that included the global Phase 3 FirstLight (TAK-861-3001) and RadiantLight (TAK-861-3002) studies, which showed that oveporexton delivered statistically significant improvements across the full range of narcolepsy type 1 symptoms assessed, including excessive daytime sleepiness, cataplexy, and other secondary measures evaluated in the trials. Oveporexton was generally well tolerated, with a safety profile that remained consistent across the clinical studies conducted so far. The most frequently reported side effects included insomnia, urinary urgency, urinary frequency, and excessive salivation.

Asuka Miyabashira, president of the Japan Pharma Business Unit at Takeda, credited the company’s scientists in Japan for their persistent work in successfully targeting the underlying orexin deficiency behind narcolepsy type 1, something that had never before been achieved. She said it is exciting for a biopharmaceutical company to discover, develop, and commercialize a treatment entirely in-house, and expressed pride in the collaboration with colleagues, healthcare providers, and the patient community that made it possible to bring this new class of treatment to adults with narcolepsy type 1 in Japan.

This approval from Japan’s health ministry marks the third regulatory clearance secured for ORZEYFUL worldwide. The medicine is also approved for treating narcolepsy type 1 in China and the United States, where its classification as a controlled substance remains under review by the U.S. Drug Enforcement Administration.

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Related Topics and Keywords

Narcolepsy Type 1, ORZEYFUL, ORZEYFUL (oveporexton)