A longer duration of extended-release naltrexone (XR-NTX) treatment in individuals with opioid dependence was associated with improved outcomes and reduced rates of relapse in a study published in Addiction.
Monthly visits for XR-NTX treatment of 395 patients with opioid dependence were retrospectively assessed. Patients were divided into subgroups according to the number of XR-NTX injections they received: 6 to 7 injections for up to 6 months (n=111); 2 to 3 injections between baseline and 2 months, or <6 injections up to 6 months (n=152); and 1 injection at baseline (n=132).
During the 6-month study period, the number of XR-NTX injections was higher in patients with private insurance vs self-payment (5 vs 2, respectively; P =.005) or vs state insurance (5 vs 2, respectively; P <.001) and in patients who were employed vs unemployed (3 vs 2, respectively; P =.02).
In the subgroup analysis, patients who had received the most XR-NTX injections were less likely to have used drugs in the recent past and more likely to have normal or minimal mental illness and to attend school.
Patients who had received 6 to 7 vs 1 to 3 XR-NTX injections experienced greater improvements in employment, mental health, and psychosocial functioning, as well as reduced opioid craving and drug use during the 6-month study period.
The study’s design did not allow them to assess statistical significance of the observed differences between groups. In addition, the lack of a control group and the observational nature of the study further limited the analysis.
“The results presented here support the continued use of XR-NTX and may help healthcare providers identify patients who will benefit from XR-NTX treatment, and should help to inform future [opioid use disorder] treatment research,” concluded the study authors.
Saxon AJ, Akerman SC, Liu CC, et al. Extended-release naltrexone (XR-NTX) for opioid use disorder in clinical practice: Vivitrol’s Cost and Treatment Outcomes Registry [published online March 1, 2018]. Addiction. doi: 10.1111/add.14199