Takeda’s narcolepsy drug approved by the FDA, a boon for new class of treatments

Aug. 5, 2026 Chen, a national biotech reporter, is the co-author of The Readout, a newsletter about the business, science, and politics of biotech. The Food and Drug Administration on Wednesday approved a novel type of treatment for narcolepsy made by Takeda, backing a drug class that scientists hope can transform the treatment of sleep disorders and potentially address a broad range of neurologic conditions. The twice-a-day pill, which will be marketed as Orzeyful, is an orexin receptor agonist. It’s cleared to treat narcolepsy type 1, a taxing condition in which patients have a deficiency of the orexin neuron and experience bouts of sleepiness and muscle weakness during the day. The drug will likely be very appealing to patients. Current therapies, stimulants and sodium oxybates, carry risk of misuse and patients still feel sleepy while taking them. In two Phase 3 trials, Orzeyful helped patients stay awake during the day for much longer than what’s been seen with current treatments. Throughout the studies, participants also reported less daytime sleepiness, less frequent muscle weakness, and greater attentiveness. This may just be the start for the orexin agonist class. Takeda and its competitors, Alkermes and Eli Lilly (through its acquisition of the biotech Centessa), are testing similar drugs in narcolepsy type 2 and idiopathic hypersomnia, other conditions in which patients feel excessively sleepy but don’t have significant orexin deficiencies. Since the orexin system not only regulates the cycle of sleeping and waking, but may also boost attentiveness and cognition, the broader goal for drugmakers is to test these treatments in a variety of neuropsychiatric conditions in which patients feel sleepy and fatigued, like Alzheimer’s disease and depression. This has been a long journey for Takeda, the first company to focus on orexin agonists, starting over a decade ago. The initial orexin pill Takeda developed had liver toxicity issues, but Orzeyful has not raised liver concerns. The most common side effects observed in trials were insomnia, increased frequency and urgency to urinate, and increased saliva production.