LAUSR

Extended-release, once-nightly sodium oxybate (ON-SXB; FT218) is under FDA review for the treatment of adults with narcolepsy. RESTORE, an ongoing, open-label extension/switch study (NCT04451668), evaluates long-term ON-SXB safety and tolerability. This interim analysis assessed dosing titration, tolerability, and study continuation. RESTORE enrolls adults with narcolepsy in 1 of 3 groups: those with prior REST-ON participation but no current oxybate use (Group A), those who switched from twice-nightly oxybates (Group B), and oxybate-naïve patients (Group C). No patients rolled directly from REST-ON to RESTORE. Initial dose for Groups A/C was 4.5 g/night. Group B switched to ON-SXB from stable doses of twice-nightly oxybate to the nearest equivalent single dose. Investigators could increase or decrease dose by 1.5-g increments weekly as needed. Descriptive statistics were used to analyze dose titration and discontinuations. At an interim data cutoff date of November 14, 2021, 99 participants were enrolled and had received ≥1 dose of ON-SXB (not currently taking oxybate, n=24; switch, n=75). For Groups A/C, 5 (21%) participants continued the 4.5-g dose, 8 (33%) increased to 6 g, 8 (33%) increased to 7.5 g, and 3 (13%) increased to 9 g by this data cutoff. Most Group B participants received initial ON-SXB doses of either 9 g (n=27) or 7.5 g (n=24). For Group B participants with >1 visit, 41 maintained their initial dose, 20 increased the dose, and 8 increased the dose but then later decreased it. All but 2 Group B participants with initial 9-g doses of ON-SXB maintained this dose. Twenty participants (20%) discontinued study treatment since the first patient enrolled in July 2020; the primary reason was withdrawal of consent (n=3; 3%). Two (2%) discontinued due to adverse reactions: vivid dreams/anxiety/lightheadedness and lack of efficacy (7.5 g); and difficulty breathing (6 g). Two discontinued due to taste/texture (2%); the remainder for miscellaneous reasons (eg, withdrew consent, could not adhere to schedule, left the country, caring for sick parent/child, wanted to get pregnant, using cannabis). These interim data indicate that the majority of participants in all groups titrated to therapeutic and tolerable doses of ON-SXB. Avadel Pharmaceuticals