Extended-Release 7-Day Injectable Buprenorphine for Patients With Minimal to Mild Opioid Withdrawal

Key Points

Newswise — Question  Is a 7-day preparation of extended-release buprenorphine feasible for patients with minimal to mild opioid withdrawal?

Findings  In this nonrandomized trial of 100 adult patients with opioid use disorder presenting with minimal to mild Clinical Opiate Withdrawal Scale scores (0-7), 7% of patients experienced precipitated withdrawal within 4 hours of 7-day extended-release buprenorphine administration, which included 3% with higher scores (4-7) and 14% with lower scores (0-3).

Meaning  Results of this study suggest that 7-day extended-release buprenorphine may be feasible in patients with opioid use disorder presenting with minimal to mild Clinical Opiate Withdrawal Scale scores (4-7), which could increase the number of patients receiving buprenorphine induction.

Abstract

Importance  Buprenorphine is an effective yet underused treatment for opioid use disorder (OUD).

Objective  To evaluate the feasibility (acceptability, tolerability, and safety) of 7-day injectable extended-release buprenorphine in patients with minimal to mild opioid withdrawal.

Design, Setting, and Participants  This nonrandomized trial comprising 4 emergency departments in the Northeast, mid-Atlantic, and Pacific geographic areas of the US included adults aged 18 years or older with moderate to severe OUD and Clinical Opiate Withdrawal Scale (COWS) scores less than 8 (minimal to mild), in which scores range from 0 to 7, with higher scores indicating increasing withdrawal. Exclusion criteria included methadone-positive urine, pregnancy, overdose, or required admission. Outcomes were assessed at baseline, daily for 7 days by telephone surveys, and in person at 7 days. Patient recruitment occurred between July 13, 2020, and May 25, 2023.

Intervention  Injection of a 24-mg dose of a weekly extended-release formulation of buprenorphine (CAM2038) and referral for ongoing OUD care.

Main Outcomes and Measures  Primary feasibility outcomes included the number of patients who (1) experienced a 5-point or greater increase in the COWS score or (2) transitioned to moderate or greater withdrawal (COWS score ≥13) within 4 hours of extended-release buprenorphine or (3) experienced precipitated withdrawal within 1 hour of extended-release buprenorphine. Secondary outcomes included injection pain, satisfaction, craving, use of nonprescribed opioids, adverse events, and engagement in OUD treatment.