Assessing Optimal XRB Initiation Points in Jail

XRB (Sublocade) will be delivered as a pre-filled 2cc subcutaneous monthly injection, using a 300mg starting dose in most cases (100mg starting doses are available per the study team's clinical judgement). XRB consists of a depot injectable formulation in polymeric solution to the abdomen and releases buprenorphine over 28-days (4-weeks) by diffusion as the polymer biodegrades. Prior to an initial injection, the participant must be stable for several days or longer on sublingual buprenorphine (SLB) at doses of 8mg/day or higher. Participants will receive at least one XRB monthly injection prior to release, which investigators anticipate to usually be the 300mg dose. Some participants will be recruited earlier during the incarceration (or experience delayed release dates and then longer than anticipated incarcerations); XRB will be continued monthly from the time of induction to the day of release.

Maintenance of existing SLB prescription (treatment as usual).