Specialized Pro-resolving Lipid Mediators and Treatment Resistant Depression

Inclusion Criteria: * Age: 18 to 65 years * Patients with treatment-resistant MDD who have not responded to at least 2 and no more than 5 antidepressant trials of at least 8 weeks duration during the current episode and have been on a current stable antidepressant regiment for at least 4 weeks. The diagnosis of MDD will be confirmed using the MINI and the historical failure to respond to antidepressant therapy will be documented using the Antidepressant Treatment Response Questionnaire (ATRQ), with failure to respond defined as less than 50% improvement by subject history. * hs-CRP ≥ 3 mg/L and ≤ 10 mg/L * BMI \>25 kg/m2 and ≤ 40 kg/m2 * 17-item Hamilton Depression Rating Scale (HAM-D) score ≥15, and \<25% decrease in score between screen and baseline Exclusion Criteria: Diagnostic Exclusions: * Meeting lifetime DSM-5 criteria for: a neurocognitive disorder, psychotic disorder, bipolar disorder, obsessive compulsive disorder, bulimia nervosa, or anorexia nervosa in the 3 months prior to the screening; any substance use disorder (except for nicotine or caffeine use disorder). * Patients who, in the investigator's judgment, pose a current, serious suicidal or homicidal risk * Presence of a serious or unstable medical illness, including insulin-dependent diabetes mellitus or bleeding disorder which, in the investigator's opinion, could compromise response to treatment, participant safety, or interpretation of study results. * Currently breastfeeding, pregnant women, or women…