Avadel Seeks FDA Approval for Sodium Oxybate to Treat Excessive Daytime Sleepiness

Avadel requested that the FDA grant final approval to the investigational sodium oxybate (Lumryz; Avadel) extended-release oral suspension to treat cataplexy—excessive daytime sleepiness (EDS)—in adults with narcolepsy, according to a recent press release.

The once-daily treatment may be safer and less disruptive than current twice-nightly treatments, which affect the sleep of patients who struggle with a sleep disorder, according to researchers.² Sodium oxybate extended-release oral suspension is being studied for long-term safety and tolerability in the open-label RESTORE clinical study.¹

“Today is an important day as we’ve taken what we believe is the last step in the NDA review process with the submission of our amendment to the [sodium oxybate] NDA seeking final approval. We look forward to working with FDA to bring [sodium oxybate] to all eligible patients as soon as possible,” said Greg Divis, chief executive officer at Avadel Pharmaceuticals, in a press release.¹

On February 24, 2023, the US Court of Appeals voted 3 to 0 in favor of requesting FDA approval for the drug.¹ Avadel had not been able to market its product because Jazz Pharmaceuticals had a Risk Evaluation and Mitigation Strategy (REMS) patent on a sodium oxybate treatment for patients with EDS.²

In 2020, investigators studied once-at bedtime sodium oxybate for safety and efficacy in the randomized, double-blind, placebo-controlled phase 3 REST-ON trial. Sodium oxybate met its endpoints, demonstrating statistically significant and clinically meaningful results for patients with EDS. It also demonstrated significance in the clinician’s overall assessment of the patient’s functioning and it reduced more EDS attacks than placebo.¹

The FDA granted sodium oxybate an Orphan Drug Designation in 2018. On July 18, 2022, sodium oxybate received tentative FDA approval. On November 18, 2022, the United States District Court for the District of Delaware ordered Jazz to delist their REMS patent from the FDA’s Orange Book, which they did on February 28, 2023.¹

Approximately 16,000 patients make up the 2-times per night oxybate market for narcolepsy, which is currently valued at $1.8 billion in the United States. In the past 3 years, experts suggest between 10,000 and 15,000 patients discontinued treatment because of the middle-of-the-night dosing. Claims data suggest that up to 50% more patients will start oxybate treatment with sodium oxybate on the market. As a result, they expect the market could grow beyond $3 billion annually.¹

“The value proposition of [sodium oxybate], demonstrated by its important benefit to people living with narcolepsy, has been our driving motivation throughout this process, and we stand ready to bring [sodium oxybate] to the narcolepsy community following an approval,” Divis said in the press release.¹

References

1. Avadel. Avadel Pharmaceuticals Requests Final FDA Approval for LUMRYZ™ (sodium oxybate) extended-release oral suspension. News Release. March 2, 2023. Accessed March 2, 2023. https://investors.avadel.com/news-releases/news-release-details/avadel-pharmaceuticals-requests-final-fda-approval-lumryztm
2. Avadel And Jazz: The Oxybate Wars - Duking It Out. December 9, 2022. Seeking Alpha. Accessed March 3, 2023. https://seekingalpha.com/article/4563443-avadel-and-jazz-oxybate-wars-duking-it-out