Efficacy and Safety Study of Narsoplimab in Pediatric Patients With High-Risk Hematopoietic Stem Cell Transplant TMA

This is a Phase 2, uncontrolled, single-dosing regimen study in pediatric patients from 28 days to less than 18 years of age with high risk HSCT-TMA. At least 4 patients will be required from each of 3 age cohorts: 28 days to \<2 years of age, 2 years to \<12 years of age, and 12 years to \<18 years of age. Treatment will be for 8 weeks and patients will be followed for up to 52 weeks.