CST3 and type 2 diabetes mellitus: In conclusion, this prospective randomized 6-month clinical study performed in insulin-treated patients with satisfactory controlled type 2 diabetes without overt CKD was the first to demonstrate the ability of vildagliptin added at the dose of 50 mg per day to reduce urinary type IV collagen excretion, serum cystatin C and to increase cystatin C-based eGFR and combined creatinine and cystatin C-based eGFR, in the absence of any significant influence on UACR.