Avadel Pharmaceuticals plc announced the publication of real-world data describing the risk of accidental dosing errors with immediate-release twice-nightly oxybate. The paper, titled Evidence of Accidental Dosing Errors with Immediate-Release Sodium Oxybate: Data From the US Food and Drug Administration Adverse Event Reporting System, was published in Drugs — Real World Outcomes. Oxybates are currently available as a twice-nightly formulation, which requires patients with narcolepsy, who already struggle with uneven and interrupted sleep, to take a first dose at bedtime and the second dose 2.5-4 hours later.

Due to the inherent risk of accidental mistakes from this dosing schedule, an analysis was conducted on post-marketing safety surveillance data from the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) to identify reports of suspected dosing errors. Data highlights are outlined below. Out of 541 reports where the second dose of an immediate-release twice-nightly oxybate may not have been taken as prescribed, 177 were submitted as serious reports and subsequently analyzed, including: Accidental early administration of the second dose resulting in adverse events (AEs; n=41); Near miss with no harm reported following early dosing (n=9); Intentionally taking second dose early (n=25); and Other inappropriate use, such as late dosing or not taking daily (n=102).

Among the 41 reports of taking the second dose too early resulting in AEs: 22% (9/41) used emergency services and 27% (11/41) resulted in hospitalizations; AEs reported with accidentally taking the second dose too early included CNS depression, bradycardia, respiratory depression, dizziness, seizure, confusion, delirium, difficulty awakening, drowsiness, falls, nausea, vomiting and enuresis; 20% of accidental early administration cases took their two doses at or almost at the exact same time; 39% consumed their second dose of immediate-release sodium oxybate oral solution less than 1 hour after the first dose; 61% took the second dose between 1 and 2.5 hours after the first dose; and There was a greater frequency of reported harm to patients in the group who took their second dose 1 hour or less after their first dose. Currently, there is no information pertaining to the risk of accidentally consuming the second dose less than 2.5 hours after the first dose or related potential patient harm in the labeling for the marketed immediate-release twice-nightly oxybate products.