Opioid users' willingness to receive prolonged-release buprenorphine depot injections for opioid use disorder.

Aims: Prolonged-release implantable and depot injection formulations of buprenorphine are very recent developments in the treatment of opioid use disorder. Such formulations remove the need for daily dosing and provide patients with sustained concentrations of buprenorphine over a period of weeks or months. We explored opioid users' personal willingness to receive prolonged-release buprenorphine depot injections and factors influencing their interest.

Methods: The study took place in London during 2018, before depot buprenorphine was licensed for use in Europe. Thirty-six face-to-face, semi-structured qualitative interviews were conducted with people who were: i) using heroin daily and not receiving any treatment for opioid use (n = 12); or ii) prescribed daily oral buprenorphine (n = 12); or iii) prescribed daily oral methadone (n = 12). Participants were asked about their willingness to receive depot buprenorphine and were encouraged to discuss factors that might alter their opinions. Interview data were analysed following the stages of Iterative Categorization.

Findings: Participants expressed a high level of willingness to receive depot buprenorphine. Their views were influenced both positively and negatively by six key features of depot buprenorphine: i) reduced contact with pharmacies and drug treatment services; ii) impact on illicit drug use and recovery; iii) the perceived effectiveness of depot buprenorphine; iv) the duration and dosage of depot buprenorphine injections; v) clinical administration of the depot buprenorphine injection; and vi) potential for side effects associated with the depot buprenorphine injection.

Conclusions: Willingness to receive a given medication is complex, individual and changeable. Opioid users seem likely to welcome greater choice and flexibility in respect of opioid agonist medications and appear more likely to accept and adhere to depot buprenorphine if it enables them to reduce their illicit drug use and facilitates their recovery. Research is now needed to assess whether patients' reported willingness to receive depot buprenorphine translates into actual uptake and adherence.