Receipt of Long-acting Injectable Buprenorphine Associated With Lower Opioid Use Disorder Treatment Retention Than Sublingual Formulation

Buprenorphine is an effective treatment for opioid use disorder (OUD) and can be delivered in sublingual (SUB) or long-acting injectable (LAI) form. In trials comparing the two, treatment retention was comparable, but less is known about efficacy in clinical practice. This study examined adults with OUD treated at a network of eight office-based OUD treatment practices in Maryland between 2019 and 2024. Researchers compared treatment retention among patients who received at least one dose of LAI (n=538) with propensity-matched controls who received only SUB (n=538). All patients had received SUB initially and standard services, including case management and mental health and substance use counseling.

• The median time retained in treatment was shorter for patients receiving LAI (269 days), compared with those receiving SUB (389 days).
• In subgroup analyses, patients who transitioned to LAI earlier in treatment (<5 appointments) had a shorter time in treatment than the SUB controls, but those who transitioned later did not.

Comments: The decreased treatment retention of patients with OUD who received LAI in this study could be due to a number of factors, including the logistics of receiving LAI, pharmacokinetics (lower or variable potency), or unmeasured confounders. Treatment retention may be improved by combining LAI with SUB, or developing higher-dose and longer-lasting formulations of LAI.

Darius A. Rastegar, MD

Reference: Deng C, Oviedo E, Fishman M, Burgess-Hall A. A comparative study of treatment retention in opioid use disorder: subcutaneous injectable versus sublingual buprenorphine. Addiction. 2025;120(10):2127–2133.