LAUSR

Patients with opioid use disorder (OUD) tend to get assigned to one of the three medications based on the treatment program to which the patient presents-e.g., opioid treatment programs tend to treat patients with methadone, while office-based practicestend to prescribe buprenorphine. It is possible that optimally matching patients with treatment type would reduce risk of returning to regular opioid use (RROU). We analyzed data from three comparative effectiveness trials (CTN0027, 2006-2010; CTN0030, 2006-2009; and CTN0051 2014-2017), where patients with OUD (N=1,459) were assigned to treatment with either injection extended-release naltrexone (XR-NTX), sublingual buprenorphine-naloxone (BUP-NX), or oral methadone. We learned an individualized rule by which to assign medication type such that risk of RROU during 12 weeks of treatment would be minimized, and then estimated the amount by which RROU risk could be reduced if the rule were applied. Applying our estimated treatment rule would reduce risk of RROU as compared to treating everyone with methadone (relative risk (RR): 0.79, 95% CI: 0.60-0.97) or treating everyone with XR-NTX (RR: 0.71, 95% CI: 0.47-0.96). Applying the estimated treatment rule would have resulted in a similar risk of RROU ascompared to treating everyone with BUP-NX (RR: 0.92, 95% CI: 0.73-1.11).