Fighting Addictions, improving Lives through COmprehensive drug rehabilitation with music (FALCO): Protocol for an international randomised controlled trial

Abstract Background Substance use disorders (SUD) are associated with a high global burden of disease, with 5.4% of all disability-adjusted life years lost due to alcohol and illicit drugs. Highly prevalent multimorbidity includes polysubstance use, mental health conditions, and other non-communicable and infectious diseases. Where traditional treatments are insufficient alone, music therapy (MT) is highly engaging and improves motivation and reduces craving; however, its long-term effects are unknown. The present study aims to examine long-term effects of active music groups (AMG) and music listening groups (MLG) versus treatment as usual (TAU) on addiction severity, recovery, and other outcomes in people with SUD Immediate and short-term effects, as well as mechanisms of these interventions, will also be examined. Methods In individuals with SUD across a wide range of age, gender, socioeconomic, and cultural backgrounds, a parallel 3-arm assessor-blinded pragmatic multinational randomised controlled trial (RCT) with embedded exploratory trials and mechanistic studies will determine long-term effects of AMG and MLG versus TAU on addiction severity (primary endpoint: 1 year), recovery, and other outcomes. Embedded trials will examine immediate effects of AMG or MLG combined with individual components of TAU combined to determine the best combinations of interventions. Experimental studies will examine mechanisms using cognitive testing and brain imaging. With 600 participants in 7 countries randomised, the trial will have 80% power on the primary outcome. Patient representatives, health technology assessment (HTA) bodies, and interventionists have been involved from conception and will ensure feasibility and applicability of the intervention across Europe. Discussion This document describes the FALCO RCT, the main part of the FALCO project, which aims to reduce disease burden through innovative, effective, and affordable treatment, and will strengthen research and innovation expertise. Recommendations from FALCO will inform intervention delivery across Europe and beyond, leading to increased safety, effectiveness, and cost-effectiveness, and improved quality of life for individuals with SUD. Stakeholders will be involved in communicating findings across all European countries and regions and ensuring that findings are effectively implemented. Trial registration ClinicalTrials.gov , NCT07028983 , registered 11 th of June 2025. https://clinicaltrials.gov/study/NCT07028983