This was a randomized, parallel-group, open-label study in which all procedures were identical for all participants until the taper period. After completing the consent process and baseline assessments, participants were inducted onto buprenorphine (Suboxone®) according to clinical practice, and stabilized on dose during the 4-week stabilization period. After the induction/stabilization phase, participants were assigned randomly to either a 7-day or 28-day tapering regimen (Table 1 ).
Participants completed weekly data collection to week 8, including the 4 induction/stabilization weeks and 4 successive weeks, so that participants in both conditions had the same number of data collection visits. Participants in both groups also attended clinic once weekly for 4 weeks after starting the taper (post-randomization) to maintain equivalence in the number of clinic visits across the two taper groups. For the 7-day taper group, medication provision ended at day 7, and medication provision extended to day 28 for the longer taper group. Follow-up interviews occurred at 1 month and 3 months post-taper.
The maximum length of study participation was approximately 5 months, including screening, induction/stabilization, taper and follow-up phases. Participants were encouraged to participate in the psychosocial treatment program administered at the treatment site (treatment as usual; TAU). Because this trial was designed to reflect real-world practice, no effort was made to standardize the psychosocial services or require participation in the psychosocial component. Following the taper, participants could continue in TAU or be referred to other local treatment resources.
The primary outcome was the percentage of participants in each taper group who were present and provided urine samples free of illicit opioids at the end of the taper period, and again at 1-month and 3-month follow-up assessments. Secondary outcomes included group comparisons of use of all drugs; withdrawal scores; the number of concomitant medications used to treat withdrawal symptoms; craving scores; and treatment satisfaction scores.
Participants completed weekly data collection to week 8, including the 4 induction/stabilization weeks and 4 successive weeks, so that participants in both conditions had the same number of data collection visits. Participants in both groups also attended clinic once weekly for 4 weeks after starting the taper (post-randomization) to maintain equivalence in the number of clinic visits across the two taper groups. For the 7-day taper group, medication provision ended at day 7, and medication provision extended to day 28 for the longer taper group. Follow-up interviews occurred at 1 month and 3 months post-taper.
The maximum length of study participation was approximately 5 months, including screening, induction/stabilization, taper and follow-up phases. Participants were encouraged to participate in the psychosocial treatment program administered at the treatment site (treatment as usual; TAU). Because this trial was designed to reflect real-world practice, no effort was made to standardize the psychosocial services or require participation in the psychosocial component. Following the taper, participants could continue in TAU or be referred to other local treatment resources.
The primary outcome was the percentage of participants in each taper group who were present and provided urine samples free of illicit opioids at the end of the taper period, and again at 1-month and 3-month follow-up assessments. Secondary outcomes included group comparisons of use of all drugs; withdrawal scores; the number of concomitant medications used to treat withdrawal symptoms; craving scores; and treatment satisfaction scores.