A randomized controlled trial of interim methadone maintenance: 10-Month follow-up

This study compares interim maintenance (IM) to a waiting list condition at an opioid treatment program (OTP). As defined by US federal regulations, IM provides observed methadone dosing and emergency counseling only for a maximum of 120 days. Three hundred and nineteen individuals enrolled on an OTP waiting list were randomly assigned on a 3:2 basis to either IM or waiting list control. Outcomes were measured at OTP entry (or at 4 months from baseline for those who did not enter treatment), and 6 months thereafter. At the second follow-up, 129 (64.8%) of the IM participants reported being enrolled in an OTP, versus 33 (27.5%) of the controls, p < .001. Significant treatment condition × time interaction effects occurred for heroin and cocaine use (both p's < .001) and the ASI Legal composite score (p < .001). Moreover, a significant difference occurred between conditions at the second follow-up for heroin-positive drug tests (interim 48.1% versus control 72.3%, p = .001) but not for cocaine-positive drug tests. At 10 months after study enrollment, there are sustained benefits of IM as compared to waiting list in terms of increased treatment entry and reduced heroin use and criminal behavior.