Early Access Program With MaaT013 in Steroid-refractory Acute Gastrointestinal Graft Versus Host Disease

Inclusion Criteria: * Age \> or = 18 * Grade III-IV gastro intestinal acute graft versus host disease with or without involvement of other organs: * patients resistant to corticosteroid (CS) and resistant to one or multiple lines of treatments * patients who cannot tolerate CS tapering, i.e., begin of CS at 2.0 mg/kg/d, demonstrate response, but show disease progress before a 50% decrease from the initial starting dose of CS is achieved. * acute GVHD with overlap syndrome Exclusion Criteria: * Active uncontrolled infection * Relapsed/persistent malignancy requiring rapid immune suppression withdrawal * Current or past veno-occlusive disease or other uncontrolled complication * Absolute neutrophil count \<500/µL for 3 consecutive days. Use of growth factor supplementation is allowed * Absolute platelet count \< 10 000/µL. Use of platelet infusion is allowed * Current or past evidence of toxic megacolon, bowel obstruction or gastrointestinal perforation * Known allergy or intolerance to trehalose or maltodextrin * Pregnancy * Breastfeeding