Faisability and Efficacity of the Reinforced Communautary Support Program (PARC) on the Complications of Chemsex

"Participants will complete the initial self-questionnaire collecting baseline socio-demographic, clinical characteristics, and all intermediate effectiveness outcome criteria \"before\". Concurrently with their participation in the program, they will complete various intermediate effectiveness evaluation questionnaires (\"after\") at 3 months (end of PARC) and 6 months (Post-PARC). Healthcare professionals running the PARC program will also complete questionnaires related to implementation indicators throughout the patients\' course (Adoption, Implementation, Maintenance).~Qualitative interviews will be conducted with patients and relevant healthcare professionals to explore barriers and drivers to the optimal deployment of the PARC program and to examine each of the Reach, Adoption, Implementation, Maintenance indicators through an organizational approach"