This Newly Approved Narcolepsy Drug Is the First to Target the Sleep Disorder's Root Cause Rather Than Its Symptoms

In early August, the Food and Drug Administration (FDA) approved the first drug that targets the root cause of a form of narcolepsy, a chronic brain disorder that causes extreme daytime sleepiness. The twice-daily oral drug, marketed as Orzeyful, could be a boon for the roughly 120,000 people in the United States with narcolepsy type 1. The disease is linked to the death of brain cells that produce orexin, a chemical that plays roles in wakefulness, sleep and muscle tone.

The loss leads to excessive daytime sleepiness, sleep paralysis, hallucinations when falling asleep and waking up, disrupted nighttime sleep and cataplexy—sudden muscle weakness while fully awake. Previous treatments for narcolepsy type 1 included stimulants to help patients stay awake and central nervous system depressants to alleviate cataplexy and improve nighttime sleep. But they only addressed symptoms of the disease.

They acted more like a “patch” than a fix, says Alex Dimitriu, a psychiatrist and sleep physician at Menlo Park Psychiatry and Sleep Medicine, to Forbes’ Claire Wolters. Orzeyful, manufactured by the Japanese pharmaceutical company Takeda, instead works by restoring the body’s orexin cycle by mimicking the natural chemical. Quick fact: Another main type of narcolepsy Some people with narcolepsy have type 2, which causes daytime sleepiness but no cataplexy.

Most individuals with this condition have normal orexin levels, and researchers still aren’t sure about the disorder’s underlying cause. The approval comes after a pair of late-stage clinical trials demonstrated Orzeyful’s efficacy and safety in 273 adults with narcolepsy type 1. For 12 weeks, participants took a high or low dose of the drug or a placebo.

Compared to the placebo group, those who received the medicine were able to stay awake longer during the day and sleep better at night. They also reported fewer cataplexy episodes. There were no serious adverse events related to treatment.

Chapman, a 19-year-old college student, tells the outlet that before enrolling in the trial, he had tried more than a dozen medications, often with severe psychological side effects. Now, thanks to Orzeyful, Chapman can follow a standard sleep-wake cycle. The drug’s success also opens the door to the use of orexin-mimicking drugs for other conditions associated with low levels of the chemical, such as attention deficit hyperactivity disorder (ADHD) and Parkinson’s disease.