The investigators retrospectively evaluted the safety and efficacy of the modified transplantation conditioning and aGVHD prophylaxis in severe aplastic anemia in 4 transplantation centers.

Aplastic anemia (AA) is a group of myelo-hemopoietic failure syndromes caused by a variety of etiologies. If not intervened, the average expected survival time is less than half a year.Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is one of the possible cures for this disease. The success rate of treatment for this disease can be further improved under the previous regimen system. The survival rate reported in the literature is 60%-90%. From Jun. 2020 to Dec. 2023, 72 patients in 4 transplantation center received this modified transplantation system, The investigators designed this clinical trial to retrospectively evaluted the safety and efficacy of the modified transplantation conditioning and aGVHD prophylaxis in severe aplastic anemia in the 4 clinical center.

Inclusion Criteria:

1. Patients who were diagnosed with severe aplastic anemia by NCCN guidelines, and has received HSCT with this transplantation preconditioning and aGVHD prophylaxis regimen;
2. Age 3-65 years old;
3. Weight 10Kg-100Kg;
4. Eastern Cooperative Oncology Group (ECOG) score ≤3;
5. No major organ injury (ECG ejection fraction >45%; bilirubin < 2 times the upper limit of normal value; AST and ALT < 3 times the upper limit of normal value; serum creatinine < 2 times the upper limit of normal value);
6. No severe infection;
7. Subjects voluntarily participated in this clinical trial and signed the informed consent.

Exclusion Criteria:

1. Patients with other hematologic diseases who are not eligible for transplantation or who do not wish to receive transplantation;
2. Patients with an expected survival of less than 1 month;
3. Patients with previous autologous or allogeneic hematopoietic stem cell transplantation;
4. pregnant patients;
5. Patients with severe mental or neurological disorders that would affect the ability to provide informed consent and/or to report or observe adverse events;
6. Other conditions that the investigator determines to be inappropriate for enrollment.

Patients who were diagnosed with severe aplastic anemia by NCCN guidelines, and has received HSCT with this transplantation preconditioning and aGVHD prophylaxis regimen;