Jazz Pharmaceuticals plc (NASDAQ: JAZZ) presented 11 late-breaking research abstracts at the SLEEP 2026 conference on June 16, covering new data on its drug Xywav (calcium, magnesium, potassium, and sodium oxybates) in patients with narcolepsy and idiopathic hypersomnia (IH).

The presentations covered two main areas. The first examined individualized dosing regimens. A post-hoc analysis from the Phase 4 DUET study showed the mean time to reach a stable dose was 42.1 days for IH patients and 41.8 days for narcolepsy patients. Data from the Xywav REMS program, which analyzed records from more than 13,000 patients, supported the feasibility of individualized dosing approaches.

The second area focused on cardiometabolic effects of Xywav's low-sodium formulation. A retrospective analysis using electronic health records showed decreases in lipid biomarkers associated with cardiovascular risk, including non-HDL cholesterol and triglycerides, following Xywav initiation. Among patients who previously used high-sodium oxybate, switching to Xywav was associated with decreases in systolic blood pressure and increases in HDL cholesterol. Secondary results from the Phase 4 XYLO study also showed that narcolepsy patients who switched from high-sodium oxybate to Xywav reported qualitative improvements in symptoms related to sodium and fluid imbalance, such as edema and nocturia.

Xywav is FDA-approved for the treatment of cataplexy or excessive daytime sleepiness in narcolepsy patients aged 7 and older, and for IH in adults. The drug contains 92% less sodium than high-sodium oxybate formulations at equivalent doses. Xywav is available only through a restricted Risk Evaluation and Mitigation Strategy program due to risks of central nervous system depression and potential for abuse.

The data were presented as part of the SLEEP 2026 annual meeting. Full abstracts are available at the conference's official website.