Using a high-affinity fibronectin-binding peptide (FUD/pUR4) that inhibits fibronectin deposition into extracellular matrix (ECM), we tested the ability of a PEGylated FUD/pUR4 (PEG-FUD) to inhibit fibrosis in the Unilateral Ureteral Obstruction (UUO) kidney disease model. Here, FN1 is linked to kidney disorder.