What is IgA, and what is IgA nephropathy (IgAN)?

IgA is an antibody circulating in the blood. In the disease IgAN, this protein has certain features that cause it to clump, and then deposit into the filtration system of the kidney. These deposits then cause the disease IgA nephropathy.

The picture on the left shows a kidney biopsy of a patient with IgAN. The disc-shaped object in the center shows a glomerulus, the main filtration unit of the kidney. There are several million glomeruli in each kidney. The right panel shows the glomerulus stained for IgA (the bright green-yellow material). A normal glomerulus should not have such staining.

Who gets IgAN?

The illness begins in early life, usually in adolescents or young adults, and progresses slowly to loss of kidney function. IgAN is most common in Asia, but occurs throughout the world, and it is the commonest cause of primary glomerulonephritis. It is likely that many people who have IgAN do not know it because they have not been tested.

How is it diagnosed?

IgAN is most often suspected in adolescents and young adults whose urine is found to contain red blood cells and protein, both not normally found in urine of healthy persons. Several disorders can cause these changes. The diagnosis of IgAN requires a needle biopsy of the kidney, which shows characteristics findings that include large amounts of IgA deposits.

How effective are current treatments?

Drugs now used to treat patients are only partially effective in slowing down the onset of kidney failure. Also, no drug in current use reverses the disease-that is, restores kidney function. With no good treatment available, up to 40% of patients will develop kidney failure over a period of years. This end stage disease requires dialysis and kidney transplantation, if they are available.

How will IGAN Bioscience's drugs treat IgAN?

Our drugs are enzymes known as IgA proteases. These enzymes will be used to cut and remove the IgA in the kidney, with the goal of restoring kidney function. IgA proteases will likely be given intravenously so they can reach the kidney in active form. The IGAN Biosciences research staff discovered the IgA proteases, and has been studying them for many years.

The drug candidates being evaluated by IGAN Biosciences are currently in preclinical stages, which involve extensive testing for efficacy and safety before being used in patients with IgAN.