Low-dose synthetic adrenocorticotropic hormone-analog therapy for nephrotic patients: results from a single-center pilot study

INTRODUCTION: This report describes our experience using a low-dose synthetic adrenocorticotropic hormone (ACTH) analog for patients affected by nephrotic syndrome who had not responded to or had relapsed after steroid and immunosuppressive treatments. PATIENTS AND METHODS: Eighteen adult nephrotic patients with an estimated glomerular filtration rate >30 mL/min were recruited. Histological pictures included ten of membranous nephropathy, three of membranous proliferative glomerulonephritis, three of minimal change, and two of focal segmental glomerular sclerosis. All patients received the synthetic ACTH analog tetracosactide 1 mg intramuscularly once a week for 12 months. Estimated glomerular filtration rate, proteinuria, serum lipids, albumin, glucose, and potassium were determined before and during the treatment. RESULTS: One of the 18 patients discontinued the treatment after 1 month because of severe fluid retention, and two patients were lost at follow-up. Complete remission occurred in six cases, while partial remission occurred in four cases (55.5% responder rate). With respect to baseline, after 12 months proteinuria had decreased from 7.24±0.92 to 2.03±0.65 g/day (P<0.0001), and serum albumin had increased from 2.89±0.14 to 3.66±0.18 g/dL (P<0.0001). Total and low-density lipoprotein cholesterol had decreased from 255±17 to 193±10 mg/dL (P=0.01), and from 168±18 to 114±7 mg/dL (P=0.03), respectively. No cases of severe worsening of renal function, hyperglycemia, or hypokalemia were observed, and no admissions for cardiovascular or infectious events were recorded. CONCLUSION: Tetracosactide administration at the dosage of 1 mg intramuscularly per week for 12 months seems to be an acceptable alternative for nephrotic patients unresponsive or relapsing after steroid-immunosuppressive regimens. Further studies should be planned to assess the effect of this low-dose ACTH regimen also in nephrotic patients not eligible for kidney biopsy or immunosuppressive protocols.