Patients'satisfaction and experience in treatment with opioid substitution therapy in Spain. The PREDEPO study

The aim of this study was to compare patients' satisfaction, experience, objectives, and opinion based on their current opioid substitution therapy (OST) (buprenorphine/naloxone (B/N) or methadone). The PREDEPO study is an observational, cross-sectional, multicentric study performed in Spain. Adult patients diagnosed with opioid use disorder (OUD) receiving OST were included. They were asked to fill in a questionnaire regarding their current OST. A total of 98 patients were enrolled (B/N: 50%, methadone: 50%). Mean age was 47 ± 8 years old and 80% were male. Treatment satisfaction was similar between groups. The most frequently reported factor for being "very/quite satisfied" was "being able to distribute the dose at different times throughout the day" (44% B/N vs. 63% methadone; p = .122). A significantly lower proportion of patients in the B/N group versus the methadone group reported that having to collect the medication daily was "very/quite annoying" (19% vs. 52%, p = .032). Treatment objectives reported by the majority of patients were similar between groups ("not feeling in withdrawal anymore", "reduce/definitely stop drug use", "improve my health", and "stop thinking about using daily") except for "not having money problems anymore" (73% B/N vs. 92% methadone; p = .012).  These results suggest there are several unmet expectations regarding current OST. There is a need for new treatments that reduce the burden of OUD, avoid the need for daily dosing, and are less stigmatizing which in turn could improve patient management, adherence and, quality of life.