Single Patient Expanded Access Treatment Plan For The Investigational Product Narsoplimab

* Patient (adult or pediatric) must have undergone allogeneic or autologous hematopoietic stem cell transplant (HSCT) * Patient must be capable of understanding an informed consent form (ICF) or the parent or legal guardian of the patient is able to understand and sign a written ICF prior to the initiation of any treatment procedures. * Patient must have HSCT- TMA defined as having thrombocytopenia and evidence of microangiopathic hemolytic anemia.