Diabetic related complications have long been reported as one of the key co-morbidity factors associated with both Type 1 and Type 2 diabetes. The FIELD study (Fenofibrate Intervention and Event Lowering in Diabetes) was developed to examine the effects of the lipid-lowering drug fenofibrate and its association with prevention of vascular pathologies such as diabetic retinopathy, limb amputation and cardiovascular incidents. The study was a double-blind placebo, controlled trial conducted with a cohort of 9,975 patients with Type 2 diabetes tracked over a period of 12 years. Blood samples were taken at baseline and during follow-up period, with initial collection after a 6 week run-in where all patients received the fenofibrate, followed by annual collections and 12 years post study close-out. Plasma samples were stored at -80C for subsequent analyses. A custom high throughput, DIA based plasma proteomics pipeline was developed and tested on an initial set of 15 patients samples that had blood collected at trial baseline and at the end of active run-in. We identified several protein markers including C4B binding protein, serotransferrin and kallistatin that show a significant change in regulation pre and post drug treatment. We are currently employing this approach to the wider FIELD study consisting of 1720 patient samples.