A Study in Children and, Adults With Congenital Thrombotic Thrombocytopenic Purpura (cTTP) Treated With Adzynma

Congenital thrombotic thrombocytopenic purpura (cTTP) is a rare blood disorder that some people are born with. It is caused by a problem in a gene passed down from parents to children, which affects the body's ability to produce a enzyme called ADAMTS13. This enzyme helps to cut down a larger form of protein called von Willebrand Factor (VWF). People with cTTP have low levels of ADAMTS13. Without ADAMTS13, large forms of vWF build up and cause blood clots in small blood vessels. These clots can block blood flow to vital organs, causing serious health problems. Adzynma is a human ADAMTS13 protein made in the laboratory. It works the same way as natural ADAMTS13 does and may provide higher levels of ADAMTS13. The main aim of this study is to learn more about the risk of children and adults with cTTP treated with Adzynma developing antibodies that prevent Adzynma from working properly (called neutralizing antibodies) within 6 months after the first treatment and to understand the risk of allergic reactions within 7 days of the first treatment with Adzynma. Other aims are to better understand how safe treatment with Adzynma is over a longer period of time (called long-term safety) in children and adults with cTTP and to gather information about pregnancies and babies of women who have received Adzynma while pregnant. Only data already available in the medical records of the people who received Adzynma for the treatment of cTTP in normal clinical practice will be reviewed and collected during this study.