First Study to Examine Narcolepsy Drug in Children, Adolescents
Sodium oxybate (Xyrem) is already approved in adults who have cataplexy and excessive daytime sleepiness with narcolepsy.
SEATTLE — The first formal randomized, placebo-controlled trial to evaluate sodium oxybate (Xyrem) for the treatment of children and adolescents with narcolepsy and cataplexy is currently enrolling patients (NCT02221869), investigators reported at SLEEP 2015.
Sodium oxybate is approved for the treatment of cataplexy — an abrupt, temporary loss of voluntary muscular function brought on by an emotional trigger such as laughter, pleasure, anger, or excitement — and excessive daytime sleepiness (EDS) in adults with narcolepsy and is recommended by the American Academy of Sleep Medicine as standard care for EDS and cataplexy in patients with narcolepsy.
“Reports from clinical practice suggest that sodium oxybate may improve narcolepsy symptoms in children and adolescents, but sodium oxybate has only been evaluated in one controlled clinical trial in adolescents,” stated Y. Grace Wang, MD, of Jazz Pharmaceuticals, Inc., Palo Alto, Calif.
The primary objective of the 52-week double-blind withdrawal trial is to evaluate the efficacy and safety of sodium oxybate for the treatment of cataplexy in patients between the ages of 7 and 17 years old with narcolepsy with cataplexy. The primary outcome efficacy measure is change in weekly number of cataplexy attacks, evaluated using a daily diary. For safety, the outcome measure is adverse events and respiratory safety.
Secondary objectives are to evaluate the efficacy of sodium oxybate for EDS, to characterize sodium oxybate pharmacokinetics using nighttime blood samples, and to evaluate the safety of sodium oxybate titration to an effective tolerable dose in this population. Outcome measures are the Clinical Global Impression of Change for cataplexy severity and EDS assessment based on changes in the Epworth Sleepiness Scale for children and adolescents.
The target enrollment is a minimum of 100 patients who have a primary diagnosis of narcolepsy with cataplexy. Patients will be randomly assigned 1:1 after the stable-dose period to receive sodium oxybate continuation or sodium oxybate placebo (ie, sodium oxybate withdrawal) for two weeks.
Patients can be either sodium oxybate-naïve or, if currently on sodium oxybate, on stable dosing with twice nightly dosing of sodium oxybate ≤9g/night, or stimulants, for ≥2 months prior to screening. Excluded will be those with “other documented clinically significant condition such as an unstable medical condition, mood disturbance, or laboratory abnormality as determined by additional study-specific criteria or the investigator,” Dr. Wang noted. Also excluded are patients taking any non-indicated, anti-cataplectic within 1 month before screening or if, in the opinion of the investigator, it is unsafe for the subject to receive placebo for 2 weeks.
“Data will help determine the efficacy benefits and will help identify safety issues associated with sodium oxybate treatment in children in children and adolescents with narcolepsy with cataplexy,” Dr. Wang noted.