Antoine Yrondi, Djamila Bennabi, Emmanuel Haffen, Marion Garnier, Frank Bellivier, Thierry Bourgerol, Vincent Camus, Thierry D’Amato, Olivier Doumy, Frédéric Haesebaert, Jérôme Holtzmann, Christophe Lançon, Philippe Vignaud, Fanny Moliere, Isabel Nieto, Raphaëlle Marie Richieri, Philippe Domenech, Corentin Rabu, Luc Mallet, Liova Yon, Laurent Schmitt, Florian Stephan, Guillaume Vaiva, Michel Walter, Pierre-Michel Llorca, Philippe Courtet, Marion Leboyer, Wissam El-Hage, Bruno Aouizerate

Major depression is characterized by (i) a high lifetime prevalence of 16-17% in the general population; (ii) a high frequency of treatment resistance in around 20-30% of cases; (iii) a recurrent or chronic course; (iv) a negative impact on the general functioning and quality of life; and (v) a high level of comorbidity with various psychiatric and non-psychiatric disorders, high occurrence of completed suicide, significant burden along with the personal, societal, and economic costs. In this context, there is an important need for the development of a network of expert centers for treatment-resistant depression (TRD), as performed under the leadership of the Fondation FondaMental. The principal mission of this national network is to establish a genuine prevention, screening, and diagnosis policy for TRD to offer a systematic, comprehensive, longitudinal, and multidimensional evaluation of cases. A shared electronic medical file is used referring to a common exhaustive and standardized set of assessment tools exploring psychiatric, non-psychiatric, metabolic, biological, and cognitive dimensions of TRD. This is paralleled by a medico-economic evaluation to examine the global economic burden of the disease and related health-care resource utilization. In addition, an integrated biobank has been built by the collection of serum and DNA samples for the measurement of several biomarkers that could further be associated with the treatment resistance in the recruited depressed patients. A French observational long-term follow-up cohort study is currently in progress enabling the extensive assessment of resistant depressed patients. In those unresponsive cases, each expert center proposes relevant therapeutic options that are classically aligned to the international guidelines referring to recognized scientific societies. This approach is expected to improve the overall clinical assessments and to provide evidence-based information to those clinicians most closely involved in the management of TRD thereby facilitating treatment decisions and choice in everyday clinical practice. This could contribute to significantly improve the poor prognosis, the relapsing course, daily functioning and heavy burden of TRD. Moreover, the newly created French network of expert centers for TRD will be particularly helpful for a better characterization of sociodemographic, clinical, neuropsychological, and biological markers of treatment resistance required for the further development of personalized therapeutic strategies in TRD.