This study uses a double-blind, placebo-controlled, randomised between groups design to test the hypothesis that, compared to placebo, 7-10 days' administration of tofacitinib 5mg twice daily has positive effects on emotional and reward processing in patients with treatment-resistant depression (TRD) and elevated C-reactive protein (hs-CRP; a marker of inflammation). Patients will have been diagnosed with Major Depressive Disorder using the Structured Clinical Interview for DSM-5 and will have shown non-response to at least 2 adequate antidepressant trials.They will also have a plasma hs-CRP of 1mg/L or greater. During the study patients will continue their antidepressant treatment. Participants will be randomised to receive 7-10 days treatment with either tofacitinib 5 mg twice daily or a matched placebo. This study includes three visits in total: a screening visit; research visit 1 (includes cognitive tests) and research visit 2 (to include an MRI scan as well as cognitive tests).
This study will test whether 7-10 day administration of the anti-inflammatory drug, tofacitinib, has positive effects on people experiencing treatment-resistant depression compared to placebo.