IGF1 and acute kidney injury: A phase 2 study to assess the safety and efficacy of ANG-3777 in patients who develop AKI after cardiac surgery is ongoing.172 Unfortunately, some clinical trials have already failed; for example, exogenous IGF-1 is beneficial in the recovery after kidney injury in mouse models, but a therapeutic trial in patients with acute renal failure (ARF) failed to demonstrate the efficacy of IGF-1 in humans because it induced a fibrotic response in mesangial cells and extensive neutrophil infiltration that reduced patient survival.56 This may be due to different renal lesions in ARF.