Perspectives on Immunotherapeutics for Opioid Use Disorder and Overdose Prevention From People Who Use Opioids (PWUOs)

Objectives: Patient advocates and online commentary have characterized immunotherapeutic approaches for opioid use disorder (OUD) as fundamentally misguided. We aimed to evaluate perspectives in the primary stakeholders, people who use opioids nonmedically (PWUOs). Methods: We randomized respondents to 3 different survey versions, testing how acceptance of opioid vaccines is influenced by calling them “vaccines” (with minimal information or additional information) versus “long-acting medications.” This survey experiment was conducted between June 2024 and June 2025 in 442 US-based adults, 18 or older, who reported past 6-month nonmedical use of opioids or past 6-month use of methadone or buprenorphine for OUD. The primary outcome measure was willingness to use a long-acting blockade-based treatment designed to the participant’s preferred duration of blockade (eg, 2–3 mo, lifelong) and targeted substances (eg, heroin, fentanyl, methamphetamine, cannabis, nicotine). Results: There were 442 respondents (52.7% women; mean age 38.9, SD 9.4; mean DSM-5 OUD criteria met 8/11, SD 3.5). Most respondents were willing to use a long-acting blockade. Willingness was higher when the treatment was described as a “medication” versus a “vaccine” with less versus more descriptive vaccine information (“very” or “kind of willing”: medication=134/150, 89%; vaccine with less information=108/142, 76%; vaccine with more information=113/150, 75%). Respondents preferred a duration of action <1 year, primarily targeting fentanyl. Conclusions: PWUOs expressed willingness to use anti-opioid vaccines, but with strong preferences for limits on duration of action and breadth of blockade. Uptake may increase if opioid vaccines offer a range of breadths and durations of action.