"This large multicentre, randomised, controlled, comparative effectiveness trial had five major findings. First, it was more difficult to start XR-NTX [Extended-release naltrexone] treatment than BUP-NX [sublingual buprenorphine-naloxone] treatment: 28% dropped out of treatment before XR-NTX induction versus only 6% before BUP-NX induction. Second, nearly all induction failures had early relapse. Third, in the intention-to-treat population of all patients who were randomly assigned, XR-NTX had lower relapse-free survival than BUP-NX, directly related to early induction failure. Fourth, for the per-protocol population, who successfully initiated medication, XR-NTX and BUP-NX were similarly effective. Finally, fatal overdose, non-fatal overdose, and other serious adverse events did not differ between treatment groups. Thus, if induction to either medication is successful, XR-NTX and BUP-NX were comparably effective and safe options. These findings afford providers, patients, and families a choice between agonist and antagonist therapies. The risk of XR-NTX induction failure should be considered, and agonist treatments for those individuals unable to complete detoxification should be encouraged."