Oral naltrexone as a treatment for relapse prevention in formerly opioid-dependent drug users: a systematic review and economic evaluation

• Published in: Health technology assessment (Winchester, England) England), 2007-02, Vol.11 (6), p.iii
• Main Authors: Adi, Y, Juarez-Garcia, A, Wang, D, Jowett, S, Frew, E, Day, E, Bayliss, S, Roberts, T, Burls, A
• Format: Article
• Language: English
• Subjects: Cost-Benefit Analysis; Counseling; Humans; Naltrexone - economics; Naltrexone - therapeutic use; Narcotic Antagonists - economics; Narcotic Antagonists - therapeutic use; Opioid-Related Disorders - drug therapy; Opioid-Related Disorders - prevention & control; Opioid-Related Disorders - therapy; Quality of Life; Quality-Adjusted Life Years; Randomized Controlled Trials as Topic; Risk; Secondary Prevention; Time Factors
• ISSN: 1366-5278; 2046-4924; 1366-5278
• DOI: 10.3310/hta11060

To investigate the clinical effectiveness and cost-effectiveness of naltrexone for relapse prevention in detoxified formerly opioid-dependent individuals compared with any strategy that does not use naltrexone, including treatment with placebo, other pharmacological treatments, psychosocial interventions or no treatment. Major electronic databases were searched from inception to September 2005. Selected studies were screened and quality assessed. Meta-analyses were carried out as appropriate. A decision-analytic model using Monte Carlo simulation was developed that compared naltrexone as an adjunctive therapy to no naltrexone. It assumed compliance rates that were not enhanced by contingent management rewards (because this is current UK practice). Utility values could not be identified from the literature and so were obtained by research specially commissioned from the Value of Health Panel. The methodological quality of the 26 randomised controlled trials (RCTs) that met the inclusion criteria was poor to moderate. The results suggest that naltrexone as maintenance therapy may be better than placebo in terms of retention in treatment, but this was not statistically significant. A meta-analysis of seven included RCTs gave the relative risk (RR) of loss of retention in treatment in the naltrexone arm as 0.94. The pooled hazard ratio (HR) reported in five of the RCTs for retention in treatment data followed up to 35 weeks was calculated as 0.90 in favour of naltrexone and also did not reach statistical significance. The risk of drug abuse in naltrexone versus placebo, with or without psychological support given in both arms, gave a pooled RR of 0.72, which was a statistically significant difference in favour of naltrexone. The pooled HR from three RCTs for opioid relapse-free rates was significantly different from placebo in favour of naltrexone 0.53; however, this fell off over time and may be of limited clinical significance. The RR of reimprisonment while on naltrexone therapy showed results in favour of naltrexone in the combined two studies of parolees or people on probation, but the number of participants was small. One study of 52 participants found that the difference in improvement score for risky sexual behaviour in the naltrexone group compared with the placebo group was not statistically significant. The adverse events data reported showed no significant difference between the naltrexone and placebo arms. The quality of the nine RCTs of intervent