A Phase 4, Pilot, Open-Label Study of VIVITROL® (Extended-Release Naltrexone XR-NTX) for Prisoners

This was a Phase 4, pilot, open-label feasibility study of extended-release injectable naltrexone (XR-NTX) administered to pre-release prisoners having a history of pre-incarceration opioid disorder. We evaluated the relationship between XR-NTX adherence and criminal recidivism (re-arrest and re-incarceration) and opioid and cocaine use. Twenty-seven pre-release male and female prisoners who had opioid disorders during the year prior to index incarceration were recruited and received one XR-NTX injection once each month for 7 months (1 injection pre-release from prison and 6 injections in the community) and of those 27, 10 (37%) were retained in treatment at 7-months post release. Results indicate those completing 6 compared to those completing <6 injections were less likely to test positive for opioids in the community (0% vs. 62.5%, respectively; p=0.003). Although not statistically significant, individuals who did not complete all 6 injections were more likely to be re-arrested compared to those completing all 6 community injections (31.3% vs. 0%, respectively; p=0.123). Contingent upon further study of a randomized controlled trial, XR-NTX may be a feasible option in the prison setting in view of the lack of potential for diversion. Furthermore, these data suggest that completing the entire course of treatment (6 injections) may reduce opioid use and, to a lesser degree, re-arrest and re-incarceration.