Drug Use After Emergency Department‐Initiated Injectable Buprenorphine: A Secondary Analysis of the ED ‐ INNOVATION Ancillary Safety and Feasibility Trial

Study Objective To characterize opioid and nonopioid drug use in the week following emergency department (ED)‐initiated extended‐release buprenorphine (XR‐BUP) treatment using both self‐reported data and urine drug screens (UDS). Methods This study uses data collected during a nonrandomized clinical trial of patients with untreated opioid use disorder (OUD), testing the safety and feasibility of initiating XR‐BUP in patients presenting with minimal to mild withdrawal. The study was conducted from July 2020 to May 2023 across four urban academic EDs in the Northeast, Mid‐Atlantic, and Pacific regions of the United States. A total of 100 participants, 18 years or older with OUD defined by DSM‐5 criteria, a clinical opiate withdrawal scale (COWS < 8), and a positive opioid urine screen were included. Individuals with recent MOUD treatment, presentation for overdose, or concurrent methadone use were excluded. All participants received a single subcutaneous injection of 24 mg XR‐BUP (CAM2038) during their ED visit. The primary outcomes were self‐reported daily opioid and nonopioid drug use over 7 days postinjection using daily Qualtrics surveys and UDS results on day 7. Results Among participants who received XR‐BUP and completed daily surveys, 98% reported at least one opioid‐free day, and 63% reported no opioid use across all 7 days. Day 7 UDS results showed decreased detection of opioids, stimulants, and benzodiazepines. Reported polysubstance use also declined over the observation period. Conclusions ED‐initiated XR‐BUP was associated with substantial reductions in opioid and polysubstance use during the first week post‐discharge, supporting its role in early overdose risk mitigation and highlighting its value as an ED‐based intervention for opioid use disorder. Trial Registration ClinicalTrials.gov Identifier: NCT03658642