ABSTRACT
Major depressive disorder (MDD) is a highly prevalent disorder, with lifetime prevalence reported at 16.2% in a U.S. epidemiological survey.1 It has great socioeconomic importance as it is the psychiatric disorder that most frequently causes psychosocial disability. Indeed, according to the World Health Organization, it will be the second leading cause of disability worldwide in terms of burden of disease. Although there is a range of medications offered to subjects with MDD that have demonstrated the ef£cacy of several classes of antidepressants, it is still unknown exactly how antidepressants exert their therapeutic bene£t. Currently available pharmacotherapy is associated with a delayed onset of several weeks and causes side effects, and still, only around 30%–45% of MDD subjects typically attain remission. The majority of subjects are at risk for chronic depression and other morbidity factors, including suicide, substance abuse, and other serious medical conditions. These unmet needs highlight the importance of investigating novel treatment options for depression.
