The study focuses on children aged 2 to under 18 who have Primary IgAN, a rare kidney condition in which a protein called immunoglobulin A builds up in the kidneys and can cause blood and protein to appear in the urine. The medication being tested is a tablet containing atrasentan (also known by the code name EXV811), which is taken by mouth. The purpose of the study is to determine whether this drug can reduce the amount of protein that leaks into the urine.
Participants will receive one tablet each day for about nine months. Throughout the study they will visit the clinic regularly, where health care staff will collect a urine sample, usually the first morning urine, and perform a simple test that compares the protein level to a normal waste product to see how much protein is present. Blood samples will also be taken to understand how the body absorbs and clears the medication. Doctors will monitor safety by checking for any side effects, routine lab results, and vital signs during the visits.



France
Spain