Dose-Finding Pilot Study of ACTH in Patients With Idiopathic Membranous Nephropathy

Inclusion Criteria: 1. Idiopathic MN with diagnostic biopsy performed less than 36 months from the time of dose randomization. 2. Age \> 18 years. 3. Patients need to be treated with an ACEI and/or ARB, for at least 3 months prior to ACTH treatment and have adequately controlled blood pressure 4. Proteinuria of \>4.0 on a 24-hour urine collection. 5. Estimated GFR \>40 ml/min/1.73m2 while taking ACEI/ARB therapy. Exclusion Criteria: 1. Age \<18 years. 2. Estimated GFR \<40 ml/min/1.73m2, or serum creatinine \>2.0 mg/dl. 3. Renal biopsy showing more than 30% glomerulosclerosis and/or tubular atrophy. 4. Patient must be off glucocorticoid, calcineurin inhibitors (cyclosporin A, tacrolimus) or mycophenolic mofetil for \>1 month, and alkylating agents or rituximab for \>6 months. 5. Resistance to the following immunosuppressive routines e.g. steroids alone, calcineurin inhibitors plus or minus steroids, cytotoxic agents plus or minus steroids. 6. Patients with active infections or secondary causes of MN. 7. Type 1 or 2 diabetes mellitus. 8. Pregnancy or nursing. 9. Acute renal vein thrombosis documented prior to entry by renal US or CT scan and requiring anticoagulation therapy.