0388 Dosing and Reasons for Transitioning From Sodium Oxybate to Lower-Sodium Oxybate in People With Narcolepsy: Data From the Real-World TENOR Study

Abstract

Abstract Introduction Lower-sodium oxybate (LXB) contains 92% less sodium than sodium oxybate (SXB) and is approved for treating cataplexy or excessive daytime sleepiness in patients with narcolepsy (aged ≥7 years) and for treating idiopathic hypersomnia in adults. The Transition Experience of persons with Narcolepsy taking Oxybate in the Real-world (TENOR) study examines the impact of transitioning from SXB to LXB in a real-world setting. Methods TENOR is a patient-centric, prospective, observational, noninterventional, virtual-format study (NCT04803786). Eligible participants include US adults with narcolepsy (type 1 or 2) transitioning from SXB to LXB within the previous/upcoming 7 days. Longitudinal data are collected for 21 weeks post-transition. These analyses include data collected at initiation of LXB treatment from all qualifying participants. Results The analyses included 85 participants with confirmed narcolepsy (type 1, n=45; type 2, n=40). Mean (SD) age was 40.3 (13.0) years; most participants were female (73%) and White (87%) and took ≥1 concomitant medication for narcolepsy at baseline in addition to SXB (79%, with 38% taking 1 concomitant medication, 33% taking 2, and 8% taking ≥3). Mean (SD) time on current SXB regimen was 57.8 (52.1) months. Almost all (96%) participants took SXB twice nightly. After transitioning, 98% of participants took LXB twice nightly. Mean (SD) total nightly SXB (n=85) and starting LXB (n=84) doses at baseline were 7.7 (1.5) g and 7.7 (1.5) g, respectively; SXB-LXB dose conversions at baseline were gram-for-gram in 87% of participants. The most common total nightly LXB dose was >7.5 g (56%), followed by >6.0 to ≤7.5 g (21%), >4.5 to ≤6.0 g (15%), and ≤4.5 g (7%). Participant-reported reasons for transitioning to LXB (multiple selections allowed) included lower sodium content for long-term health (93%), physician recommendation (47%), to avoid cardiovascular issues (39%), to avoid side effects (31%), to improve control of narcolepsy symptoms (18%), and other (14%). Conclusion The majority of participants transitioned from SXB to LXB using a gram-for-gram dose conversion. The most common reason cited for switching was for long-term health due to the lower sodium content of LXB. Support (If Any) Jazz Pharmaceuticals.