Originally, it was designed with the goal of continuously recruiting people who inject psychoactive substances in order to better understand the individual and contextual factors of HIV transmission and to characterize the issues specific to treatment access and its effects. Since 2004, the objectives of the cohort have been revised to include studies on the natural history of HCV infection and re-infection. In 2015, a mental health section was added to study the relationships between mental health problems, including psychiatric diagnoses and mental states, and the transmission of HCV and HIV among people who inject substances.
The computerized database and biological samples were set up for the identification and validation of mechanisms from clinical, virological and immunological parameters relevant to transmission, disease progression and immune responses. This bank is also associated with several network projects, and is part of the International Consortium of Prospective Hepatitis C Cohorts (NC3).