In a phase 2, randomized, double-blind, placebo-controlled study of ruboxistaurin in patients with type 2 diabetes and persistent albuminuria, patients randomized to ruboxistaurin had a significant decrease in albuminuria while maintaining a stable eGFR and urinary TGF-β level, whereas those randomized to placebo had an increase in their albuminuria and urinary TGF-β levels as well as a decrease in their eGFR [148, 149]. Here, TGFB1 is linked to type 2 diabetes mellitus.