Granulocyte Colony-Stimulating Factor-Primed Bone Marrow Transplantation Experience in 350 Matched Sibling Donor...

For matched related hematopoietic cell transplantation (HCT) for non-malignant diseases, most centers prefer bone marrow (BM) over peripheral blood stem cell (PBSC) grafts owing to increased risk of chronic graft-versus-host disease (GVHD-associated with the latter. BM generally entails delayed neutrophil and platelet recovery compared with PBSC transplants. Granulocyte colony-stimulating factor-primed bone marrow (G-BM) has been associated with faster hematologic recovery while retaining a decreased risk of GVHD. Moreover, it may allow for reduced marrow collection volumes.

We retrospectively analyzed our experience with G-BM as graft source from July 2015 to February 2023 across 350 consecutive first matched sibling transplants in children with severe thalassemia in four centers in India.

We observed that G-BM is associated with rapid hematologic recovery with relatively low rates of cytomegalovirus reactivation (16%), low rates of moderate to severe GVHD (grade 3-4 acute GVHD was 5% and moderate to severe chronic GVHD was 3%), and reduced marrow collection volumes (12.5 ml/kg of donor's weight), and thus is potentially safer for both donors and recipients compared with standard bone marrow. This observation was made in a relatively homogenous cohort of multiply transfused patients with thalassemia who are at high risk of rejection. None of the donors required third-party blood transfusion irrespective of donor-recipient weight discrepancy.

Our experience suggests that G-BM is associated with prompt engraftment and very low rates of moderate or severe GVHD. It also appears to be safe for donors and decreases the risk for third-party red blood cell transfusions. Finally, it is relatively easy and inexpensive to collect. G-BM should be strongly considered as a preferable graft source in matched-related donor transplantations for thalassemia and potentially other transplant indications.