Specialized Pro-resolving Lipid Mediators and Treatment Resistant Depression

This R33 application builds directly on a previous collaborative R01 (NCT00517036) and UG3 (NCT02553915) grants. The investigators will carry out a 12-week, randomized placebo-controlled, double-masked, augmentation trial of 4 g/day eicosapentaenoic acid (EPA)-enriched omega-3 treatment in adults with major depressive disorder (MDD), an inadequate response to antidepressants (treatment-resistant depression \[TRD\]), body mass index (BMI) \>25 kg/m2 and ≤ 40 kg/m2, and inflammation (high sensitivity C reactive protein \[hs-CRP\] ≥ 3 mg/L and ≤ 10 mg/L). It is hypothesized that 4 g/day of EPA-enriched omega-3 will: 1) Significantly increase plasma 18-hydroxy eicosapentaeoic acid \[18-HEPE\] concentrations compared to placebo (primary biological endpoint); 2) produce significantly greater increases in plasma 18-HEPE concentration since baseline for sustained MADRS responders (those with at least 50% reduction since baseline in MADRS scores at both treatment week 8 and week 12) than for (a) unsustained/non-responders to EPA-enriched n-3 as well as (b) placebo-supplemented sustained responders (secondary biological endpoint).