A Phase 1b/2 Open-label Study to Evaluate Safety, Tolerability, Pharmacokinetics, and Exploratory Efficacy Following Fosigotifator Administration in Adult and Pediatric Subjects With Vanishing White Matter Disease

Inclusion Criteria: 1. Males and females \>= 6 months of age at the time of Screening. 2. Have VWM disease defined as: 1. A clinical diagnosis by a physician experienced in the assessment of VWM disease; and 2. A molecular diagnosis of VWM disease, and 3. A magnetic resonance imaging (MRI) presentation consistent with VWM disease. 3. Have a designated caregiver who is able to complete the respective caregiver-centered assessments. 4. Signed and dated informed consent provided by the participant, or from a legally authorized representative (LAR) if participant is incapable to consent…