About Primary Hyperoxaluria Type 1 – PH1

Primary Hyperoxaluria Type 1, or 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 may eventually cause kidney failure.

Causes of PH1

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. Excess oxalate combines with calcium in the kidneys to form crystals called calcium oxalate which simply means there is excess calcium buildup in the kidneys, which often leads to painful and recurrent kidney stones. This can result in chronic kidney disease or nephrocalcinosis, and ultimately liver failure also called end stage renal disease (ESRD).

Primary Hyperoxaluria Type 1 Symptoms and Treatments

Symptoms of PH1 can start any time from infancy to adulthood, but regardless of when it starts, people with PH1 are at high risk to develop renal failure, a failure of the kidneys to filter waste material from the body. Once the kidneys are no longer able to process the extra oxalate produced by the liver, oxalate can deposit in other places in the body causing a serious condition called systemic oxalosis.

Current PH1 treatments are primarily intended to reduce the harmful buildup of calcium oxalate in the kidney and other places. The investigational medication, lumasiran (ALN-GO1), is currently being evaluated in the ILLUMINATE clinical research studies for its safety and ability to reduce oxalate production.

Current treatment options that can help people with PH1 include:

  • Drinking large amounts of water can help to prevent oxalate crystals from building up and forming stones.
  • Some medicines help prevent oxalate from forming crystals in the urine
  • Some people also benefit from vitamin B6 treatment.
  • A kidney and/or liver transplant may also be considered.

PH1 Information and Resources

For more information, talk to your physician about support organizations in your area.