Extended-release Naltrexone Is Not Linked to Hepatotoxicity in Adults Experiencing Homelessness and Alcohol Use Disorder

Abstract

Objectives The use of extended-release naltrexone (XR-NTX) as treatment for alcohol use disorder (AUD) has been limited by a prior black box warning for hepatotoxicity. We performed a secondary analysis of data from a randomized clinical trial to compare serum liver enzyme levels for those randomized to XR-NTX versus placebo. Methods The parent study aimed to test the efficacy of combined pharmacobehavioral harm-reduction treatment in improving alcohol and quality-of-life outcomes for adults experiencing homelessness and AUD. We compared the 2 arms that received intramuscular injections of either 380 mg XR-NTX (n = 74) or placebo (n = 77). Outcomes included (a) liver enzyme levels and (b) liver enzyme values categorized as normal (<1× upper limit of normal [ULN]), elevated (1–3× ULN), or high (>3× ULN). We performed multinomial logistic regression and negative binomial generalized estimating equations modeling to assess the effects of treatment group and the time × treatment group interaction on liver enzyme outcomes. Results The mean age was 47.9 ± 9.9 years, and the mean baseline alcohol consumption was 23.2 ± 14.0 drinks per day. There were no significant differences in the development of liver enzyme elevations 1 to 3× ULN or more than 3× ULN (all Ps > 0.25) or in the change in liver enzyme values (all Ps > 0.41) between the placebo and the XR-NTX groups over the treatment course. Conclusions In our study of adults experiencing homelessness and AUD, receipt of XR-NTX was not associated with hepatotoxicity. These findings support the use of XR-NTX to treat AUD even in patients who are drinking heavily and physiologically dependent on alcohol.