The new European Medicines Agency guideline on antidepressants: a guide for researchers and drug developers.

According to the World Health Organization (WHO), depressive disorders are currently considered as one of the most disabling medical conditions in the world with one of the highest disability-adjusted life years [1] and this situation has apparently been further worsened during the COVID-19 pandemic [2]. Up to two thirds of patients with major depressive disorders (MDD) do not achieve full remission following an adequate first line standard of care and/or experience residual symptoms such as anxiety, impaired cognition, fatigue, sleep disturbance, or anhedonia [3]. Several attempts are often needed to find the most suitable treatment [4].

A Delphi-method-based consensus guideline for definition of treatment-resistant depression for clinical trials.

Criteria for treatment-resistant depression (TRD) and partially responsive depression (PRD) as subtypes of major depressive disorder (MDD) are not unequivocally defined. In the present document we used a Delphi-method-based consensus approach to define TRD and PRD and to serve as operational criteria for future clinical studies, especially if conducted for regulatory purposes. We reviewed the literature and brought together a group of international experts (including clinicians, academics, researchers, employees of pharmaceutical companies, regulatory bodies representatives, and one person with lived experience) to evaluate the state-of-the-art and main controversies regarding the current classification.