ASC930 in Patients With Steroid-Refractory Acute Graft Versus Host Disease (SR-aGVHD)

Inclusion Criteria: * Participants ≥ 2 months of age * Diagnosis of aGVHD grade II-IV following allogeneic HSCT according to standard criteria (Harris, 2016). * Diagnosis of SR-aGVHD according to Mohty (2020) * Meet one of the following criteria: * Participants who are Ruxolitinib-refractory, according to Mohty (2020) * Participants who are not eligible for SOC therapy * Participants who agree to receive ASC930 as a second-line therapy * Karnofsky/Lansky Performance Status of at least 30 at the time of study entry * Minor participants must be capable of giving written assent as appropriate per the applicable age (per local regulatory requirements). Exclusion Criteria: * Diagnosis of active Hepatic Sinusoidal Obstruction Syndrome (SOS) * Presence of an active uncontrolled infection * Active treatment for a hyprecoagulation disorder * Evidence of diffuse alveolar hemorrhage or other active pulmonary disease * Evidence of encephalopathy as defined by a change in mental status since the onset of aGVHD * Evidence of relapse of malignancy * Receival of agents other than steroids for primary treatment of aGVHD * Severe allergic history to cell-based products