0785 Sodium Oxybate Treatment of Pediatric Narcolepsy: Effects on Weight, Height, and Pubertal Development

Abstract

Abstract Narcolepsy commonly begins in childhood/adolescence, with weight gain and precocious puberty often occurring after onset. Sodium oxybate (SXB) was evaluated as a treatment for cataplexy and excessive daytime sleepiness in pediatric patients through a placebo-controlled, randomized-withdrawal study. The results of body mass index (BMI) and pubertal assessments are reported. Children and adolescents with narcolepsy with cataplexy who were on SXB or SXB-naïve were eligible. SXB-naïve participants were titrated to an optimal dose, then entered a stable dose period (SD); participants on SXB entered the SD on their usual dose. After a two-week double-blind, placebo-controlled randomized-withdrawal period, participants entered an open-label safety period (OL) for a total study duration of up to 1 year. Weight/height were recorded at each visit. BMI was compared to CDC percentile charts. Sex and growth hormones were assessed at the beginning and end of the double-blind period and at the end of the OL. Analyses were derived from a 10 February 2017 datacut; 106 were enrolled: 74 SXB-naïve and 32 on SXB at entry; 79 were in the study ≥ 6 months and 46 completed 1 year. Mean±standard deviation BMI percentile at baseline was 86.7 ± 17.6 (overweight) for SXB-naïve participants and 75.5 ± 27.1 (normal) for participants on SXB at entry. Mean BMI percentile decreased in SXB-naïve participants by the end of dose titration (79.8 ± 22.7, normal). In participants completing 1 year, mean BMI percentile at week 52 was 66.4 ± 29.9 (normal, SXB naïve, n=31) and 68.6 ± 26.5 (normal, on-SXB, n=15). There were 13 adverse events of weight loss (11 SXB naïve); 3 participants became underweight (BMI percentile <5); they continued in the study and were within normal range by completion/termination. At study end, mean height percentile remained unchanged. No adverse effects were seen on growth or sex hormones, and there were no signs of premature puberty. Participants were overweight/near-overweight at study entry. Mean BMI percentile decreased over the course of the study, and was within normal range at study end. No change in height or pubertal status was observed. Jazz Pharmaceuticals.