About PH1

PH1 is a rare, inherited condition that occurs when the liver makes too much of a substance called oxalate. This can result in painful and recurrent kidney stones, and eventually cause kidney failure.

Symptoms of PH1 can start during infancy, childhood, or adulthood. Children and adults with PH1 have a genetic change that prevents the liver from making enough of a certain protein (an enzyme called alanine-glyoxylate transaminase, or AGT) that normally prevents the buildup of oxalate. Because they don’t have enough of this AGT enzyme, extra oxalate is produced.

Excess oxalate causes problems when it combines with calcium in the kidneys to form crystals called calcium oxalate. This results in nephrocalcinosis, which simply means there is excess calcium buildup in the kidneys, and often leads to painful and recurrent kidney stones. People with PH1 eventually have renal failure. Once the kidneys can’t process the extra oxalate produced by the liver, oxalate also spreads to other places in the body, causing a serious condition called systemic oxalosis.

Current management of the disease aims to reduce the harmful buildup of calcium oxalate in the kidney and other places. Although there is no cure for PH1, drinking large amounts of water can help to prevent oxalate crystals from building up and forming stones. Some people also benefit from vitamin B6 treatment. A liver transplant may also be considered, as replacing the patient’s liver will provide back the missing AGT enzyme. A kidney transplant may also be considered when the kidneys worsen and get close to failing.

For more information, talk to your physician about support organizations in your area and visit the Oxalosis and Hyperoxaluria Foundation.

Find out about taking part in our current and future PH1 clinical research studies.