Treatment of thrombotic microangiopathy after hematopoietic stem cell transplantation with recombinant human soluble thrombomodulin

BACKGROUNDTransplant-associated thrombotic microangiopathy (TA-TMA) after hematopoietic stem cell transplantation (HSCT) remains a severe complication associated with underlying endothelial damage. TMA has a high mortality rate with no definite treatments and effective treatments are needed. STUDY DESIGN AND METHODSThe study objective was to retrospectively analyze the outcome of patients receiving recombinant human soluble thrombomodulin (rTM), which has cytoprotective effects against calcineurin inhibitor-induced endothelial cell damage, or other therapeutics for TA-TMA from 254 consecutive HSCT recipients between 2009 to 2014 at a single institution. We hypothesized that patients receiving rTM as a first-line treatment would receive a benefit. RESULTSSixteen patients were diagnosed as TA-TMA. Of these 16 patients, nine were treated with rTM (rTM group), and seven received treatment other than rTM (control group) as a first-line therapy. Seven of the nine patients in the rTM group recovered from TA-TMA without complications, but none in the control group recovered. The rTM group showed a significantly better overall survival after TA-TMA onset than did the control group (median, 123.0 days vs. 45.5 days, respectively; p=0.045). The cumulative incidence of acute graft-versus-host disease was the same in both groups (56% vs. 57%, respectively; p=0.52) on Day 100 after TA-TMA onset. CONCLUSIONThis is the first report evaluating rTM administration for TA-TMA compared with previous treatments. Our data suggests that rTM might offer a better clinical outcome in patients with TA-TMA.