A double-blind study (PRO-814) recruited adults (18 to 65 years) with a primary diagnosis of opioid dependence who had received at least 24 weeks of sublingual buprenorphine at a stable daily dose ≤8mg for at least 90 days with no evidence of opioid withdrawal or urine sample positive for illicit opioids within the preceding 90 days. Buprenorphine implant significantly increased the proportion of patients without evidence of illicit drug use for 4 out of 6 months compared with sublingual buprenorphine-naloxone by about 8%. The submitting company presented a cost-utility analysis evaluating the use of the buprenorphine implant within its full licensed indication. The analysis compared buprenorphine implant with sublingual buprenorphine-naloxone (Suboxone®) and sublingual buprenorphine. Subcutaneous buprenorphine (Buvidal®) was also included as a comparator in the model. Clinical experts broadly agreed these were the relevant comparators. Key weaknesses: • The assumption that patients on the buprenorphine implant will have less frequent visits to the addiction clinic is a source of uncertainty and potentially not in line with the licensed indication. The ICERs were upwardly sensitive to assuming no differences in clinic visits. The submitting company also provided further sensitivity analysis assuming that there was a 50% reduction in clinic visits for Sixmo®. This gave results of £3,699 and £14,015 versus SL BPN/NX and SL BPN respectively and £376,545 (south-west quadrant) versus SC BPN. • The extrapolation of the clean urine curve is likely to create an overly optimistic result and the alternative approach using the observed values extrapolated is more appropriate. • The submitting company may have been overly optimistic with regards to implant-site related adverse events in the model with regards to implant-site related adverse events in the model for a patient population of relevance in the Scottish clinical setting. There could be disutilities not included, thus creating an overly optimistic base case. • The hospitalisation data were sourced from DORIS to reflect the Scottish setting, but the rates sourced from PRO-814 are more appropriate. Despite these limitations, the economic case was demonstrated.