This clinical trial is focused on studying a rare condition known as Vanishing White Matter disease, which affects the brain and nervous system. The study will explore the effects of a treatment called Fosigotifator, which is being tested to see if it is safe and well-tolerated by both adults and children with this disease. Fosigotifator is a type of medication known as a prodrug, which means it is converted into an active form in the body, specifically into a compound called A-1684909.
The purpose of the study is to evaluate the safety and tolerability of Fosigotifator in patients with Vanishing White Matter disease. Participants will take the medication in the form of film-coated granules, which are taken orally. The study will involve regular visits to monitor the participants’ health, including checking vital signs, conducting physical exams, and performing brain scans using MRI technology. The study will also measure the levels of the active compound, A-1684909, in the blood and cerebrospinal fluid over time.
Throughout the study, participants will be closely monitored for any side effects or changes in their condition. The trial will last for several weeks, with follow-up visits to ensure the safety and effectiveness of the treatment. This research aims to provide valuable insights into the potential benefits of Fosigotifator for individuals with Vanishing White Matter disease, contributing to the development of new treatment options for this challenging condition.



The Netherlands