Off-label treatment of a 17-year-old female patient with anorexia nervosa (AN), major depressive disorder (MDD), obsessive-compulsive disorder (OCD), posttraumatic stress disorder (PTSD), and non-suicidal self-injury (NSSI) with human recombinant leptin (metreleptin) for two dosing periods of 15 and seven days was associated with self- and clinician-rated improvements of eating disorder related psychopathology, OCD, depression, and NSSI. This evidence concerns the gene LEP and major depressive disorder.