Co-infusion of Treg-enriched Donor Lymphocytes With CD3-depleted Hematopoietic Stem Cell Graft to Prevent Graft-versus Host Disease After Allogeneic Hematopoietic Stem Cell Transplantation Among Children With Hematologic Malignancies

The combination of partial T depletion and pharmacological immunosuppression minimized in volume and duration will combine the advantages of T depletion (early engraftment, low risk of GVHD, low risk of organ complications) and pharmacological prophylaxis (restoration of anti-infective immunity).

Pharmacological prophylaxis of GVHD is one of the key subjects of evaluation in the current study. Since the optimal pharmacological approach is not known, the allocation of the patients to study groups will be by randomization procedure, although not for the purpose of direct comparison, but for unbiased descriptive analysis. There will be four main groups and an additional group to be open for allocation based on the main group closing for fitting the stopping rules. The details of pharmacological GVHD prevention are Sirolimus 1 mg -3 till +30 4-8 ng/ml

Pharmacological prophylaxis of GVHD is one of the key subjects of evaluation in the current study. Since the optimal pharmacological approach is not known, the allocation of the patients to study groups will be by randomization procedure, although not for the purpose of direct comparison, but for unbiased descriptive analysis. There will be four main groups and an additional group to be open for allocation based on the main group closing for fitting the stopping rules. The details of pharmacological GVHD prevention regimens are Ruxolitinib 5 mg -2 till +30

Pharmacological prophylaxis of GVHD is one of the key subjects of evaluation in the current study. Since the optimal pharmacological approach is not known, the allocation of the patients to study groups will be by randomization procedure, although not for the purpose of direct comparison, but for unbiased descriptive analysis. There will be four main groups and an additional group to be open for allocation based on the main group closing for fitting the stopping rules. Abatacept 10 mg/kg -1, +7, +14, +28