A double-blind, randomized, placebo-controlled clinical trial on benfotiamine treatment in patients with diabetic nephropathy.

To investigate the effect of benfotiamine on urinary albumin excretion (UAE) and the tubular damage marker kidney injury molecule-1 (KIM-1) in patients with type 2 diabetes and nephropathy. Patients with type 2 diabetes and UAE equivalent to 15-300 mg/24 h, despite ACE inhibitors (ACE-Is) or angiotensin receptor blockers (ARBs), were randomly assigned to 12 weeks of benfotiamine (900 mg/day) (n = 39) or placebo (n = 43). Compared with placebo, benfotiamine treatment resulted in significant improvement of thiamine status (P < 0.001). Benfotiamine treatment did not significantly decrease 24-h UAE or 24-h KIM-1 excretion. In patients with type 2 diabetes and nephropathy, high-dose benfotiamine treatment for 12 weeks in addition to ACE-Is or ARBs did not reduce UAE or KIM-1 excretion, despite improvement of thiamine status.