Evaluation of Recombinant Humanized Anti-CD25 Monoclonal Antibody for Preventing Graft-versus-host Disease After Haploidentical/matched Unrelated Donor Hematopoietic Stem Cell Transplantation in Patients with Transfusion-dependent Thalassemia

Inclusion Criteria:

• patients with transfusion-dependent thalassemia;

• patients who are planning to receive matched unrelated donor hematopoietic stem celltransplantation (MUD-HSCT) or HLA haploidentical donor hematopoietic stem celltransplantation (HID-HSCT);

• physical condition score (Lansky/Karnofsky score) ≥ 70%;

• patients (or legal guardians) voluntarily participate in the study and sign theinformed consent form

Exclusion Criteria:

• patients with HLA-matched hematopoietic stem cell donors and willing to receiveHLA-matched hematopoietic stem cell transplantation;

• patients with known infectious diseases such as hepatitis B, hepatitis C, AIDS,syphilis, human T-lymphotropic virus, etc.;

• patients with serious active bacterial, viral, fungal, malaria or parasiticinfections;

• patients with autoimmune deficiency diseases;

• patients with a history of malignant tumors or current malignant tumors;

• patients with important organ diseases or abnormal laboratory tests, including butnot limited to: 1) patients with cirrhosis, liver fibrosis or active hepatitis,and/or abnormal liver function tests (alanine aminotransferase (ALT) and aspartateaminotransferase (AST) ≥2.5×ULN; alkaline phosphatase ≥2.5×ULN); 2) patients withheart disease, or left ventricular ejection fraction (LVEF) <60%, or severe irondeposition in the heart; 3) kidney disease, or blood creatinine ≥1.5×ULN withcreatinine clearance <30% of normal level; 4) patients with endocrine dysfunction;

• patients with uncorrected bleeding disease;

• patients with severe mental illness (such as severe depression, schizophrenia, etc.)or cognitive dysfunction (dementia, delirium, etc.), which are unable to cooperatewith the study;

• peripheral blood white blood cell (WBC) count <3×10^9/L or platelet count <100×10^9/L;

• patients having received thalidomide treatment within the past 3 months;

• patients having received any type of gene and/or cell therapy in the past;

• patients with severe allergies;

• female patients who are pregnant, breastfeeding, or planning to become pregnantwithin 1 year of participating in this trial;

• patients who are participating in other clinical trials;

• other situations that are not suitable for participation in this clinical trial asassessed by the investigator.