Evaluating treosulfan vs reduced-intensity busulfan conditioning for allogeneic hematopoietic cell transplantation in older patients with acute myeloid leukemia

This study aimed to compare the outcomes of allogeneic hematopoietic cell transplant (alloHCT) for older patients with acute myeloid leukemia (AML) using treosulfan (Trecondi) compared to reduced intensity busulfan (Myleran) conditioning. 

This study concluded that treosulfan conditioning appears to be more suitable for these patients.  

AlloHCT is frequently the only curative treatment for patients with AML. Allo HCT involves the transplantation of healthy stem cells from a donor. Before alloHCT, a conditioning regimen is used. Conditioning regimens involve powerful chemotherapy that kills bone marrow cells. This makes room in the bone marrow for new cells to grow and prevent the rejection of transplanted cells.

Reduced-intensity conditioning (RIC) uses less chemotherapy and radiation than the standard regimen. Older patients are usually more fragile and need a RIC regimen in order to prevent side effects. RIC using busulfan in combination with fludarabine (Fludara) is often used in these patients. Treosulfan can also be used in combination with fludarabine as a conditioning regimen before transplant. Studies have shown that treosulfan is associated with fewer side effects. However, whether treosulfan conditioning is suitable for older patients with AML before alloHCT is still unknown.  

This study involved 570 patients with AML undergoing alloHCT. Patients were treated with intravenous (IV) fludarabine with either treosulfan (group 1) or RIC busulfan (group 2). Patients were followed up for an average of 2.5 years.  

After 36 months, 59.5% of the patients in group 1 were alive without complications from AML compared to 49.7% in group 2. After 36 months, 66.8% of patients in group 1 were alive compared to 56.3% in group 2. Side effects were similar between groups. 

This study concluded that treosulfan conditioning appears suitable for older patients with AML undergoing alloHCT.  

The patients knew which treatment they were getting. This may have influenced the results. This study was funded by Medac, the manufacturer of treosulfan.