FDA Sets Date for Xyrem® Review Meeting

Minneapolis, MN - April 11, 2000

The Food and Drug Administration (FDA) has rescheduled an advisory committee review of Xyrem® (sodium oxybate) oral solution on June 6, 2001. The Peripheral and Central Nervous System Drugs Advisory Committee will provide advice and recommendations to the FDA regarding the safety, efficacy and risk management of Xyrem.

An Advisory Committee meeting had been previously scheduled at which Xyrem was to be reviewed. The FDA requested more time so that Orphan Medical could respond to the agency's request for clarification of supplemental data outside of Orphan Medical sponsored trials. The Company responded with additional information, and the FDA extended by ninety days the date by when it would take action on the New Drug Application (NDA).

As defined by the FDA, Advisory Committees are established to help the agency make sound decisions based on good science in its review of regulated products. Advisory committees consist of individuals who are recognized as experts in their field from many different sectors including medical professionals, scientists and researchers, industry leaders, and consumer representatives and patient representatives.

"The FDA has been actively reviewing the information we provided. In addition to supporting the FDA in its review of the NDA and preparing for the June meeting," said John Bullion, Chairman and CEO of Orphan Medical, "we've also been very busy responding to the many patients who have expressed their desire in having Xyrem available for the treatment of cataplexy, a debilitating symptom of narcolepsy for which there currently are no approved medicines."

The Company submitted a NDA requesting approval of Xyrem as a treatment for narcolepsy, particularly cataplexy and to improve the symptoms of excessive daytime sleepiness, on October 2, 2000. The NDA received priority review status from FDA with a six-month review goal. A ninety-day extension was granted on March 30, which moves the action deadline to early July.

Narcolepsy is a chronic neurological disorder affecting an estimated 100,000 to 125,000 Americans, whose main symptoms are excessive daytime sleepiness and cataplexy. Cataplexy is a debilitating symptom characterized by loss of muscle control in response to strong emotional reactions such as laughter, anger, or surprise.