Questcor Pharmaceuticals, a biopharmaceutical company, announced that results from an investigator-initiated clinical study involving two major academic research centres examining the dosing and effectiveness of HP Acthar Gel (repository corticotropin) in 20 patients with nephrotic syndrome due to idiopathic membranous nephropathy (iMN) have been published in the journal Nephrology Dialysis Transplantation. The paper appears in the current online edition of the journal.

The results demonstrate that Acthar can be a potentially useful therapy for inducing remission of proteinuria in patients suffering from nephrotic syndrome secondary to iMN.  The study also found that clearance of anti-PLA2R antibodies, which are an immunological marker of iMN disease activity, typically preceded or paralleled improvements in proteinuria as a result of Acthar treatment in patients with detectable antibody levels.  Acthar was generally well tolerated by patients during the course of the study, with the most common side effects being mood changes, weight gain and transient insomnia.  The study was conducted at the Mayo Clinic and the University of Toronto, with funding provided through a research grant from Questcor.

"This important independent academic study adds significantly to the growing body of clinical evidence for Acthar in the treatment of patients suffering from idiopathic types of nephrotic syndrome," said Steve Cartt, chief operating officer of Questcor.  "As a company, we continue to actively support both company-sponsored research and independent academic research evaluating Acthar in on-label indications such as the one studied in this trial, as well as in other autoimmune and inflammatory disorders having high unmet medical need."

The study involved patients with biopsy proven iMN who were randomised 1:1 to receive Acthar at a dose of either 40 or 80 units administered twice weekly following an initial induction period.  Changes in proteinuria, albumin, cholesterol profile, estimated glomerular filtration rate and serum anti-PLA2R antibodies were assessed at baseline and in response to treatment along with tolerance and safety.

Baseline characteristics included mean proteinuria (9.1±3.4 g/day), albumin (2.7±0.8 g/dL), estimated glomerular filtration rate (77±30 ml/min) along with elevated total and low-density lipoprotein (LDL) cholesterol.  By 12 months of follow-up, there was a significant improvement in proteinuria in the entire cohort, decreasing to 3.87±4.24 g/day (p < 0.001) with significant improvements in serum albumin (p=0.001), total cholesterol (p < 0.001) and LDL (p=0.001).  A > 50 per cent decrease in proteinuria was noted in 65 per cent 13/20) of the patients with a trend towards better outcomes among patients who received greater cumulative doses.

Nephrotic syndrome is a nonspecific kidney disorder characterised by a number of signs of disease including, but not limited to, proteinuria, hypoalbuminemia and edema.  It is characterised by an increase in permeability of the capillary walls of the glomerulus leading to the presence of high levels of protein passing from the blood into the urine (proteinuria at least 3.5 grams per day per 1.73m2 body surface area); low levels of protein in the blood (hypoproteinemia or hypoalbuminemia), ascites and in some cases, edema; high cholesterol (hyperlipidemia or hyperlipemia) and a predisposition for coagulation.  If inadequately treated, nephrotic syndrome can lead to end stage renal disease and may require long-term dialysis or renal transplant in some patients.