Phase 3 REVITALYZ Study Examines Extended-Release Sodium Oxybate for Idiopathic Hypersomnia

A fully enrolled phase 3 trial is evaluating whether extended-release sodium oxybate (ER-SXB) can provide a once-nightly treatment option for adults with idiopathic hypersomnia (IH). Presented at the 2026 SLEEP Annual Meeting, held June 14-17, in Baltimore, Maryland, the REVITALYZ study (NCT06525077) will assess the efficacy and safety of ER-SXB in 157 adults with IH using a double-blind, placebo-controlled randomized withdrawal design.¹

Led by Richard K. Bogan, MD, FCCP, FAASM, principal of Bogan Sleep Consultants and associate clinical professor at the University of South Carolina School of Medicine, REVITALYZ enrolled adults with a primary diagnosis of IH, an Epworth Sleepiness Scale (ESS) score greater than 11 among those not receiving oxybate therapy, and an average nightly sleep duration exceeding 7 hours. Participants undergo a 10-week dose-titration period followed by a 2-week stable-dose phase before entering a 2-week randomized withdrawal period, during which they were assigned in a 1:1 ratio to either continue ER-SXB or switch to placebo.¹

The primary efficacy end point is worsening in ESS total score during the randomized withdrawal period among participants switched to placebo compared with those who remain on active treatment. Key secondary outcomes include changes in Idiopathic Hypersomnia Severity Scale (IHSS), Functional Outcomes of Sleep Questionnaire (FOSQ), Patient Global Impression of Change, and Clinical Global Impression of Change scores.

Among the 157 enrolled participants, 83% were women and the mean age was 39.8 years. Investigators reported that approximately 26% of participants transitioned into the study from immediate-release oxybate therapy, while an additional subset had prior oxybate exposure. Enrollment was completed in December 2025, with additional efficacy and safety findings expected in future analyses.

ER-SXB was developed to provide therapeutic drug exposure throughout the night following a single bedtime administration. The approach differs from currently available immediate-release oxybate therapies, which are commonly administered in 2 nightly doses, requiring patients to awaken approximately 2.5 to 4 hours after sleep onset for a second dose. According to investigators, a once-nightly formulation may offer practical advantages for patients with IH, many of whom experience severe sleep inertia and difficulty awakening.¹

IH is a chronic neurologic sleep disorder characterized by excessive daytime sleepiness, prolonged sleep duration, unrefreshing sleep, and sleep inertia that can substantially impair daily functioning and quality of life. Although treatment options have expanded in recent years, the disorder remains associated with significant symptom burden, and many patients continue to experience persistent daytime impairment despite available therapies.²

The study enters an evolving treatment landscape for IH. In 2021, the US Food and Drug Administration approved calcium, magnesium, potassium, and sodium oxybates (Xywav) as the first therapy specifically indicated for adults with IH, based on findings from a phase 3 randomized withdrawal trial demonstrating improvements in sleepiness and overall symptom burden.³ Additional therapies, including pitolisant and orexin-targeted agents, are also being investigated as potential treatment options for the disorder.⁴

Because REVITALYZ remains ongoing and efficacy data have not yet been reported, conclusions regarding the clinical utility of ER-SXB cannot yet be drawn. Nevertheless, the study is expected to provide important information regarding whether a once-nightly oxybate formulation can maintain symptom control while potentially reducing the treatment burden associated with overnight redosing.

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REFERENCES
1. Bogan RK, Harsh J, Ibrahim S, et al. REVITALYZ: A Phase 3, Double-Blind, Placebo-Controlled, Randomized Withdrawal Trial of Extended-Release Sodium Oxybate for Idiopathic Hypersomnia. Presented at: SLEEP Annual Meeting; June 14-17, 2026; Baltimore, MD.
2. Terzaghi M, Sartori I, Tassi L, et al. Evidence of Dissociated Arousal States During NREM Parasomnia from an Intracerebral Neurophysiological Study. Sleep. 2009;32(3): 409–412. doi: 10.5665/sleep/32.3.409
3. Dauvilliers Y, Arnulf I, Foldvary-Schaefer N, et al. Efficacy and safety of lower-sodium oxybate in adults with idiopathic hypersomnia: a phase 3 randomized withdrawal study. Lancet Neurol. 2022;21(1):53-65. doi: 10.1016/S1474-4422(21)00368-9
4. Harmony Biosciences Provides Update on the Status of the Supplemental New Drug Application for Pitolisant in Idiopathic Hypersomnia. Harmony Biosciences. News Release. February 19, 2025. Accessed: June 16, 2026.