By Aakash B

(Reuters) – The U.S. Food and Drug Administration approved Jazz Pharmaceuticals Plc’s treatment for patients with a form of sleep disorder, the company said on Wednesday.

The drug, solriamfetol, will treat excessive sleepiness in adult patients with narcolepsy or obstructive sleep apnea (OSA).

Solriamfetol is expected to be commercially available in the United States following the final scheduling decision by the Drug Enforcement Administration (DEA), Jazz said in a statement.

The approval comes as Jazz is trying to reduce its reliance on its blockbuster narcolepsy drug, Xyrem, whose patents were declared invalid by a U.S. appeals court in July.

Xyrem is an approved treatment for excessive daytime sleepiness and cataplexy in patients with narcolepsy. It brought in sales of $1.4 billion in 2018 and accounted for about 70 percent of company’s revenue.

“Jazz is trying to reduce its reliance on Xyrem, and solriamfetol will be one of the drugs it plans to launch to do that,” Mizuho Securities USA analyst Irina Koffler said ahead of the agency’s decision.

“Solriamfetol is expected to be an important driver of both diversification and growth,” RBC Capital Markets analyst Randall Stanicky said in a note ahead of the approval.

Solriamfetol is expected to bring in revenue of $314 million by 2024, Stanicky said.

Narcolepsy is a chronic sleep disorder with overwhelming daytime drowsiness and sudden attacks of sleep, while obstructive sleep apnea is a potentially serious sleep disorder that can cause breathing to repeatedly stop and start.

“Narcolepsy is very disabling to people as they often get diagnosed young and stop their education and drop out of high school or college,” Koffler said.

“Sleep apnea is a different problem in the sense that a lot of people don’t know they have it, have trouble breathing at night and they even fall asleep during the day.”

(Reporting by Aakash Jagadeesh Babu and Supriya Roy in Bengaluru; Editing by Richard Chang)