Methadone Treatment is Associated with Less Opioid Use And Better Retention Compared with Buprenorphine/Naloxone

Methadone and buprenorphine are both better than placebo at reducing opioid use and retaining people with opioid use disorders in treatment. In previous studies, at higher doses the benefits from both medications were similar. However, studies of methadone and buprenorphine have been limited to less than 1 year. Researchers conducted a single follow-up interview of participants who were enrolled in opioid treatment programs in an open-label, randomized 24-week trial of buprenorphine/naloxone versus methadone to determine differences in mortality, treatment participation, and opioid use. Of the 1269 trial participants, 797 were interviewed to assess treatment participation and opioid use during the 5-year follow-up period.

• There was no significant difference in mortality between participants randomized to methadone (5.8%) compared with buprenorphine/naloxone (3.6%).
• Treatment periods during which participants received either methadone or buprenorphine/naloxone were associated with decreased opioid use over the follow-up period, compared with those periods during which participants received no treatment.
• Participants randomized to methadone spent more months in any treatment compared with the buprenorphine/naloxone group (63% versus 52% of follow-up months, respectively).
• Fewer participants randomized to methadone compared to those randomized to buprenorphine/naloxone were using opioids by self-report or urine toxicology (41% versus 51%) at the follow-up interview, even though participants could switch between buprenorphine/naloxone, methadone, or no treatment during the follow-up period.

Comments:

This study finds that methadone increased treatment participation and reduced opioid use more than buprenorphine/naloxone. Importantly, the data were obtained by following a large number of participants over an extended period of time, allowing participants to cycle between treatment(s) and no treatment, similar to real-world settings. However, care must be taken when interpreting the data, as participants were recruited from methadone clinics and a greater proportion of the buprenorphine/naloxone group dropped out of the study, requiring an adjustment in the randomization protocol.

Todd Kerensky, MD† and Alexander Y. Walley, MD, MSc

Reference:

Hser YI, Evans E, Huang D, et al. Long-term outcomes after randomization to buprenorphine/naloxone versus methadone in a multi-site trial. Addiction. 2016;111(4):695–705.