PAI-1 x vWF x tPA

This phase II trial tests how well defibrotide works in preventing transplant-associated thrombotic microangiopathy (TA-TMA) in patients with high-risk neuroblastoma undergoing tandem transplants (hematopoietic stem cell transplant [HSCT]). TMA is a potential life-threatening complication of stem cell transplant. TMA is a possible side effect of the chemotherapy (conditioning regimen) patients receive to help treat high-risk neuroblastoma, because these medicines can sometimes damage the blood vessel walls in the body. This damage leads to formation of tiny blood clots in organs, especially the kidney. This then causes organ damage and leads to problems with how they function. This study may help researchers learn how defibrotide may help prevent TMA before it starts, or help treat it once it starts among patients with high-risk neuroblastoma undergoing tandem transplants.

This research study is being done to determine the safety and tolerability of increasing doses of defibrotide within a single patient with sinusoidal obstructive syndrome (SOS)/veno-occlusive disease (VOD) after hematopoietic cell transplantation (HCT) associated with either kidney and/or lung impairment that has not obtained a complete response (CR) or progressed in severity with standard doses of defibrotide.

Sinusoidal Obstruction Syndrome (SOS), also referred to as hepatic veno-occlusive disease (VOD), is rare but serious complication of allogeneic stem cell transplantation (allo-SCT). Defibrotide is the only FDA approved therapy to treat SOS and has significantly improved outcomes. When applied early, SOS symptoms often quickly improve and an abbreviated course can be applied. This study is looking at an abbreviated 5 day course of defibrotide in those patients with a complete response to therapy with the primary outcome being day 100 overall survival as compared to history data.