Trajectory classes of opioid use among individuals in a randomized controlled trial comparing extended-release naltrexone and buprenorphine-naloxone.

To advance understanding of medication treatments for opioid use disorder (OUD), identification of distinct subgroups and factors associated with differential treatment response is critical. This study examined trajectories of opioid use for patients with OUD who were randomized to (but not in all cases inducted into) buprenorphine-naloxone (BUP-NX) or extended-release naltrexone (XR-NTX), and identified characteristics associated with each trajectory.

This secondary analysis of data from CTN-0051, Extended-Release Naltrexone vs. Buprenorphine for Opioid Treatment (X:BOT), used growth mixture models to identify distinct trajectories of days of opioid use among a subsample of 535 individuals with OUD who participated in the original 24-week randomized controlled trial of BUP-NX (n=281) or XR-NTX (n=254).

Four distinct opioid use trajectory classes were identified for BUP-NX (near abstinent/no use (59%); low use (13.2%); low use, increasing over time (15%); and moderate use, increasing over time (12.8%)). Three distinct opioid use trajectory classes were found for XR-NTX (near abstinent/no use (59.1%); low use (14.6%); and moderate use, increasing over time (26.4%)). Across both BUP-NX and XR-NTX, the near abstinent/no use class had the highest number of medical management visits. Within BUP-NX, the low use class had a greater proportion of individuals with a previous successful treatment history compared with other classes. Within XR-NTX, the moderate use, increasing over time class had the highest proportion of Hispanic participants compared with other classes.

Conclusions: Findings highlight the significant heterogeneity of opioid use during a randomized controlled trial of BUP-NX and XR-NTX and several factors associated with longitudinal patterns of opioid use that can be effectively targeted in the context of active clinician monitoring and adaptive treatment strategies tailored to patient needs. Policies that increase access and adherence to medication treatment, alongside an understanding of the unique patterns of medication response and the factors that influence it, will be critical in reducing the current opioid crisis.

Related protocols: CTN-0051