“These study findings have immediate clinical relevance for treatment of opioid use disorder at a time when an opioid epidemic continues unabated in the United States,” wrote Maria Sullivan, M.D., Ph.D., of Columbia University and colleagues. “Given that postdetoxification outpatient treatment without pharmacotherapy yields poor completion rates, high (60%−90%) relapse rates, and heightened risk of overdose and death, XR-naltrexone may be a viable alternative to prevent relapse in patients seeking treatment for opioid use disorder who do not prefer an agonist approach [such as methadone or buprenorphine].”
Sullivan and colleagues enrolled 60 adults aged 18 to 60 who met DSM-IV criteria for opioid dependence in the study. All participants completed an inpatient medication-assisted opioid withdrawal program and were transitioned to naltrexone therapy. Thirty-two patients were randomly assigned to treatment with oral naltrexone (50 mg/day) and 28 were assigned to treatment with XR-naltrexone (380 mg per injection every four weeks) for 24 weeks.
All participants were asked to visit the clinic three times per week for the first two weeks and then twice weekly for the remainder of the 24-week study. During each clinic visit, the patients took a urine test, discussed any recent substance use, and received a behavioral therapy session. The goal of the behavioral therapy was to educate, motivate, and support patients through the process of opioid detoxification, naltrexone induction, and successful naltrexone maintenance. Therapy goals were reinforced with a reward system whereby patients could win gift vouchers after achieving goals or milestones.
After six months, 12 of the 28 (43%) patients receiving XR-naltrexone had dropped out of treatment, compared with 23 of 32 (72%) patients in the oral naltrexone group. There were no significant differences in side effects between the two groups, other than a higher rate of insomnia among patients taking oral naltrexone. There were nine serious adverse events, but only one was found to be related to medication: one patient receiving XR-naltrexone developed allergic hives and was removed from the study.
“These results support the use of XR-naltrexone combined with behavioral therapy as an effective treatment for patients seeking opioid withdrawal and nonagonist treatment for preventing relapse to opioid use disorder,” the researchers concluded.
To read more about naltrexone, see the Psychiatric News article “Low-Dose Naltrexone May Mitigate Severity of Opioid Withdrawal During Detox.”