Treatment outcomes of long-acting injectable naltrexone versus oral naltrexone in alcohol use disorder in veterans

INTRODUCTION: In veterans, the prevalence of 12-month and lifetime alcohol use disorder (AUD) is 14.8% and 42.2%, respectively. Alcohol use disorder treatment is often plagued by medication discontinuation with relapse rates being as high as 39% in patients who sought treatment. One proposed benefit of long-acting injectable (LAI) medications is improved adherence. The purpose of this trial was to compare the difference in time to relapse between patients on oral and LAI naltrexone. METHODS: This study was a retrospective electronic chart review of patients with AUD who were treated with oral or LAI naltrexone at a Veteran's Affairs Medical Center from August 1, 2016, to July 31, 2018. The primary outcome assessed was time to relapse. Secondary outcomes for this study included medication possession ratio (MPR), comorbid mental health diagnosis, substance use, past pharmacological treatment, liver and kidney function, and enrollment in addiction-focused psychosocial therapy. RESULTS: Thirty-two patients met inclusion criteria. The median time to relapse was longer for those treated with LAI naltrexone versus oral naltrexone (150.5 days vs 50.5 days, P < .01). The MPR was similar among both groups (P = .47). No significant differences were found between the groups regarding safety outcomes. DISCUSSION: Results suggest that LAI naltrexone is associated with increased time to relapse and should be considered as a first-line option for patients. Given the retrospective nature and small sample size of this study, larger, randomized, controlled trials comparing LAI and oral naltrexone head to head would help determine most appropriate treatment for these patients.