A Stanford scientist found what causes narcolepsy.  Now the first pill aimed at that cause is available, and in trials patients stayed awake about five times longer

Adults with narcolepsy type 1 can now get a prescription for Orzeyful, the first pill that targets the disease’s cause instead of individual symptoms, Takeda announced Thursday.  The drug became available after the Drug Enforcement Administration classified it as a Schedule IV controlled substance, meaning low potential for abuse, in a rule that took effect the same day.  The FDA approved it in August.

What it means for patients

Narcolepsy type 1 causes overwhelming daytime sleepiness and cataplexy, a sudden loss of muscle control.  It affects about 120,000 people in the U.S., and only about half are diagnosed, according to Takeda.  Orzeyful is prescribed by a doctor and dispensed through Accredo Specialty Pharmacy, and Takeda offers help with insurance steps.  It has not announced a price.

In two 12-week trials, people on the 2-milligram dose went from staying awake about 5 minutes in a dark, quiet room to about 24 minutes, while people on placebo got slightly worse, the FDA-approved label shows.  Doctors consider 20 minutes or more normal.  Weekly cataplexy attacks fell from about 33 to 7 on the drug, compared with 46 to 29 on placebo.

Side effects were common:  60% of people on the higher dose had trouble sleeping at night, compared with 1% on placebo, and 58% had to urinate more often.  The label says it can’t be taken with drugs that strongly block CYP3A, a liver enzyme that breaks down many medicines, so patients should review their other prescriptions with a doctor or pharmacist.

How it works

People with the disease lose the brain cells that make orexin, a chemical that keeps us awake.  Orzeyful switches on one of orexin’s receptors, the docking sites where it acts.  Stanford’s Emmanuel Mignot, who directs the Stanford Center for Narcolepsy, discovered that narcolepsy is caused by the immune system destroying about 70,000 of those cells, his faculty profile says.  He was the principal U.S. investigator in the trials.

Source:  Takeda news release, Nov. 12, 2026; Orzeyful prescribing information, FDA; DEA interim final rule, Federal Register, Nov. 12, 2026; Stanford profile of Emmanuel Mignot.