Potential Narcolepsy Treatment Gets Orphan Drug Designation

The Irish-based Avadel Pharmaceuticals announced this morning that FT 218, its once-nightly product for the treatment of narcolepsy, has been granted Orphan Drug Designation by the U.S. Food and Drug Administration (FDA).

The basis for the designation is the expectation for the drug, a formulation of sodium oxybate using the company’s proprietary Micropump technology, to be clinically superior to the same drug already approved for the same patient population. The candidate is currently undergoing testing in a Phase 3 clinical trial for the treatment of excessive daytime sleepiness (EDS) and cataplexy in patients suffering from narcolepsy.

Narcolepsy is a chronic brain disorder characterized by poor control of sleep-wake cycles. Patients with the condition experience periods of EDS and sudden, irresistible stints of sleep that can occur at any time. These “sleep attacks” can last anywhere between a few seconds and several minutes. The disorder can greatly affect daily activities, as people may unwillingly fall asleep while at work, eating, or driving.

Cataplexy is typical in patients with narcolepsy, and is characterized by the sudden loss of muscle tone, and can include the loss of voluntary muscle control while awake. An estimated 70% of people with narcolepsy have cataplexy.

In 2002, the FDA approved Xyrem (sodium oxybate) oral solution, and in January of 2017, a generic version developed by Roxane Laboratories, Inc. was also approved.

“Receipt of Orphan Drug Designation for FT 218 is meaningful for both Avadel and patients suffering from Narcolepsy,” said Mike Anderson, Avadel’s Chief Executive Officer. “Narcolepsy is a debilitating and rare sleep disorder for which limited treatment options exist. We look forward to completing our REST-ON Phase III trial this year and are hopeful that FT 218 can provide meaningful benefit to patients and their quality of life over other standards of care.”

The REST-ON Phase 3 clinical trial is a double-blind, randomized, placebo controlled study intended to evaluate the safety and efficacy of FT 218 for extended-release oral suspension. The study has enrolled 264 patients and is still recruiting. Primary outcome measures include longer maintenance wakefulness test (MWT) sleep latency, improvement in CGI sleepiness scores, and fewer cataplexy attacks as recorded by Sleep and Symptom Daily Diary.

The new FDA designation comes after safety concerns of the currently approved Xyrem arose. Serious side effects have been reported in patients who were administered Xyrem, including seizures, difficulty breathing, changes in alertness, coma, and even death. Additionally, sodium oxybate is the sodium salt of gamma hydroxybutyrate (GHB), which has historically been used to facilitate sexual assault.

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