A 12-week direct comparison study found once-monthly Vivitrol (extended-release naltrexone; Alkermes) to be non-inferior to daily buprenorphine-naloxone for preventing relapse to opioid dependence following detoxification.
Researchers in Norway conducted an open-label, randomized-controlled study with 159 opioid-dependent patients who were in the detoxification stage. Participants were randomized to either daily sublingual buprenorphine-naloxone (4 to 24mg/day – target dose of 16mg/day), or once-monthly injectable extended-release naltrexone 380mg for a total of 12 weeks.
Sixty-six percent of participants completed the study. Results showed that all primary endpoints for non-inferiority of extended-release naltrexone were met: retention in treatment (P=0.04), group proportion of total number of opioid-negative urine drug tests (P<0.001), days of heroin use (P<0.001) and days of other illicit opioid use (P<0.001).
Significantly less heroin cravings were reported in the extended-release naltrexone group; treatment satisfaction was also reported higher in this group compared to the buprenorphine-naloxone group. “These data showed that treatment with extended-release naltrexone was as effective as buprenorphine-naloxone, the current standard of treatment, in maintaining short-term abstinence from heroin and other illicit opioids,” said lead investigator, Lars Tanum, MD, PhD, Akershus University Hospital, Norway.
Four participants in the extended-release naltrexone group and 6 in the buprenorphine-naloxone group terminated treatment due to adverse events. Although none were considered directly related to the treatment.
Those participants who completed the 12-week trial were invited to participate in a 36-week extension. The extension portion has already been completed and results are expected to be submitted to peer-reviewed journals shortly.
For more information visit Alkermes.com.