Dopaminergic Therapy for Anhedonia - 2

Depression is a widespread disorder (lifetime prevalence \>20%). Current antidepressant medications are effective for many patients; however, more than 30% fail to respond. Of the patients that do respond to treatment, some continue to suffer with primary symptoms of depression like an inability to experience pleasure, called anhedonia. In this regard, one biological pathway that may contribute to symptoms of depression and particularly anhedonia is inflammation. The purpose of this 8-week, double-blind, placebo-controlled, study is to explore new treatment options for people with depression who have high inflammation and anhedonia. Despite evidence of low dopamine function in patients with depression, the ability of existing dopaminergic therapies, like L-DOPA, to affect brain circuits in depression has yet to be explored. This study will help determine whether an FDA-approved medication, Sinemet (L-DOPA), might be used in the future to treat sub-groups of depressed individuals. Seventy male and female participants with depression, between 25-55 years of age, with higher levels of inflammation and anhedonia will be randomized to receive L-DOPA or matched placebo over 8 weeks. Participants will complete lab tests, medical and psychiatric assessments, motivation and motor tasks, and MRI scans as part of the study. The total length of participation is approximately 10 to 12 weeks.