The standard therapy which is employed for the treatment of HAAA is allogenic bone marrow (BM) transplantation treatment from HLA matched siblings [13, 54] . HAAA is mostly occurring in children and it would be easier to find the HLA matched donor. As HAAA shows poor prognosis, most often it has been treated by hematopoietic stem cell transplantation [26, 55] . Immunosuppressive therapy has proved effective after BM transplantation. Various immunosuppressive drugs named Antithymocyte Globulin (ATG) and Cyclosporine have been administered without eliciting any acute side effects. Steroids such as Glucocorticoids have also been employed in combination with immunosuppressive medications for the treatment of the HAA patients [26] . A durable remission from HAA has been achieved by the administrating high dose of Cyclophosphamide (CY), a highly immunosuppressive, which elicits its effect by readily destroying the lymphocytes and committed myeloid cells. The haemopoietic stem cells are not susceptible to the toxic effects of the CY due to releasing the aldehyde dehydrogenase enzyme which inactivates the drug. However, restoration of haematopoesis process may achieved by high dose of CY which mediates autoimmune attack on haematopoiectic stem cells HSCs [13] .