This is a feasibility study and the goal of this project is to evaluate whether peak ACC GABA and glutamate, quantified as a CSF-corrected absolute concentration percent change from baseline, is associated with clinical remission, Montgomery Asberg Depression Rating Scale (MADRS) total score of <10, to the anti-glutamatergic antidepressant ketamine. As MRS is expensive, we also aim to study a correlation between change in peripheral metabolites (GABA and glutamate) and central GABA and glutamate levels.
Feasibility treatment study in adults with treatment-resistant depression assessing whether changes in ACC GABA and glutamate after IV ketamine predict clinical remission (MADRS <10).
Biomarkers include dynamic fMRS of GABA/glutamate and peripheral LC-MS measures; protocol describes two IV ketamine infusions (0.5 mg/kg over 40 minutes) with blood sampling pre- and post-treatment.
Open-label, single-group two-infusion ketamine feasibility arm.
Two IV infusions 0.5 mg/kg infused over 40 minutes; biomarkers collected pre- and post-treatment.