Long-term follow-up study of community-based patients receiving XR-NTX for opioid use disorders

Extended-release naltrexone (XR-NTX) is FDA-approved to prevent relapse in patients with Opioid Use Disorder. However little is known about long-term use among community-based outpatients.

Retrospective chart review and long-term follow-up survey among individuals (N = 168) who entered an outpatient XR-NTX trial between 2011 and 2015, during which participants were offered three monthly injections of XR-NTX at no cost. The survey consisted of 35 questions covering a total of four domains: (1) substance use; (2) treatment continuation; (3) barriers; and (4) attitudes.

Fifty-seven respondents were successfully surveyed, including 50% of those initially receiving all three XR-NTX injections ("study completers") in the parent study. Study completion was associated with superior outcomes and less likely relapse (defined as daily use), with a much greater time to relapse despite higher rates of concurrent non-opioid substance use. However the majority of participants discontinued treatment with XR-NTX at study completion, largely due to attitudes of "feeling cured" and "wanting to do it on my own" rather than external barriers such as cost or side effects.

Patients who initiate treatment with XR-NTX might benefit from anticipatory guidance and motivational techniques to encourage long-term adherence as many will experience internal barriers to continuation. Our findings are reassuring that few patients experience side effects or adverse events complicating the effectiveness or safety of long-term use of XR-NTX.

Among outpatients who successfully receive 3 monthly XR-NTX injections, many will prematurely discontinue treatment due to internal attitudes, such as "feeling cured." (Am J Addict 2017;26:319-325).