A Prospective Observational Study in Naturalistic Settings to Describe Long Acting Buprenorphine Introduction in France: Change in Severity of Addiction and Health Related Quality of Life Over a Period of 6 Months.

Context The current available pharmacological treatment formulations (i.e., daily formulations of buprenorphine or methadone) for OUD in France may have several inconveniences, such as: compliance, burden of daily intake, and risk of misuse; that may hinder their effectiveness. Long acting formulations of buprenorphine (LAB) such as Buvidal have been developed to favor retention and compliance and minimize the risk of diversion. The previous studies are promising on the advantage of LAB to treat opioid addiction, however more evidence is needed in the French healthcare context.

In a French pilot study of Buvidal initiation, one third of subjects stopped Buvidal treatment prematurely (before the 3-month follow-up) but some were back on treatment at the 6-month follow-up. Buvidal seems to be promising to maintain patients in treatment, compared to daily buprenorphine, but there are late drop-outs and some of the early drop-outs may resume treatment. A 6 months follow-up would allow to explore this phenomenon and better characterize medium term LAB compliance.

None of the previous or underway studies examined the effect of Buvidal on craving over time or the cues-craving-use relationship in daily life. Chronic opioid use generates intense reactivity to opioid-conditioned cues, including craving and opioid seeking behavior. Craving is a very dynamic phenomenon across a day and its variations are best captured by Ecological Momentary Assessment (EMA) method. Previous EMA studies from SANPSY highlighted a unidirectional prospective link between cues, craving and use. EMA method would be appropriate to describe the effect of Buvidal on craving, opioid use, and the relationship between cues, craving and opioid use.

In addition to randomized clinical trials, the French National Healthcare Agency (HAS "Haute Autorité de Santé") recommends conducting "real-life" studies (i.e., in naturalistic conditions) during the development of a medication and the use of "Patient Reported Outcome Measures" (PROMs) to analyze patient quality of life and/or other measures relevant to patients (e.g., severity, efficiency), without interpretation of the answers by a health professional. However, the absence of a control group could overlook several important potential biases. In the context of this study, a randomized control trial (RCT) design would not be appropriate, but the use of a Historical Cohort control group design is an alternative. ADDICTAQUI is an ongoing longitudinal naturalistic open cohort ongoing since 1994 at SANPSY/University of Bordeaux. It includes participants initiating treatment for OUD and uses assessments similar to the current study.

In this regard, our study proposes to use the Addiction Severity Index (ASI) self-report questions and several scales on treatment satisfaction and quality of life to collect the patient's opinion of perceived changes following the use of Buvidal.