Living with

Hemophilia A?

The Alta Study is testing a potential
one-time lasting treatment

What is gene therapy?

Gene therapy is a treatment approach that attempts to treat a genetic problem at its source. When a mutated gene occurs in your body, it can affect how your cells create proteins and how those proteins behave, leading to disease. Gene therapy attempts to add a working copy of a defective gene to the patient’s cells, helping the cells function normally. This is different from a traditional drug-based approach, which may treat symptoms but not the actual genetic problems.

Since genes can’t be delivered into cells on their own, they need to have a helper, called a vector. Viruses are often used as vectors because they can easily penetrate the cell. Once inside, the information in the gene is used by the cell to build RNA and proteins. The proteins (or RNA) can then carry out their job in the cells. SB-525, the investigational drug in this study, is a type of gene therapy.

How does SB-525 work?

For hemophilia A, the goal is to deliver a normal gene into liver cells so they can produce the right amount of the clotting factor VIII to allow adequate clotting. The vectors this study uses are adeno-associated viruses (AAV) that have been changed so they can carry genes that are potentially therapeutic. These viruses infect humans but don’t cause any known disease. These viruses have been changed in the laboratory so they can no longer grow or reproduce in the human body.

These vectors are introduced into your body with a single intravenous infusion of SB-525. The gene coding for normal factor VIII then travels to your liver and enters the liver cells. In this way, the liver cells will produce factor VIII and release it into your blood. Because the gene is added into your DNA, it may enable production of factor VIII for a long time.

This is something that will be evaluated in this study. Right now the ALTA study is testing SB-525 for hemophilia A. To learn more about this study opportunity, please contact us at

doctor testing

You may qualify for the ALTA clinical research study if you:

  • Are a male age 18 or older
  • Have severe hemophilia A and are currently free of inhibitor
  • Have had factor VIII replacement therapy for at least 150 days

People who qualify will receive:

  • Investigational gene therapy (SB-525) for severe hemophilia A
  • Study-related medical care

Think the ALTA study may be for you? Contact us.