Recombinant human granulocyte colony-stimulating factor and decitabine treatment delay relapse after transplant for patients with acute myeloid leukemia

This study aimed to investigate if the combination of recombinant human granulocyte colony-stimulating factor (rhG-CSF; Filgrastim) and decitabine (Dacogen) would be effective in preventing relapse after transplant for patients with high-risk (HR) acute myeloid leukemia (AML).  

This study concluded that this treatment combination can reduce the occurrence of relapse in these patients.  

Allogeneic stem cell transplant (allo-SCT) involves stem cells from a healthy donor being transferred to a patient. The aim of a transplant is to replace cells lost during cancer treatment and help with the production of new healthy cells. However, relapse is a major cause of treatment failure after allo-SCT for patients with HR-AML.  

RhG-CSF stimulates the bone marrow to produce white blood cells and stem cells and releases them into the bloodstream. Decitabine is a chemotherapy that can be used for AML treatment. Recent studies have shown that decitabine prevents relapse. However, it was unknown if rhG-CSF combined with small-dose decitabine would help to prevent relapse after allo-SCT in patients with HR-AML. 

This study involved 202 patients with HR-AML who had received allo-HSCT. All patients were minimal residual disease (MRD) negative. MRD-negative means there were no cancer cells left in the body after treatment. Patients were split into two groups. Patients were randomly assigned to receive either rhG-CSF with small-dose decitabine (group 1) or no treatment (group 2). Patients in group 1 were followed up for an average of 28 months and those in group 2 for an average of 26.4 months. 

At 2 years, relapse occurred in 15% of patients in group 1 and 38.3% in group 2. 85.8% of patients in group 1 and 69.7% of those in group 2 were alive after 2 years. 

At 2 years, long-term graft versus host disease (GVHD) occurred in 23% of patients in group 1 compared to 21.7% in group 2. GVHD is a complication of allo-SCT where the transplanted cells attack the body. In group 1, increased numbers of natural killer (NK), CD81 T, and regulatory T cells were seen. These cells indicate an effective immune system.  

93% of patients in group 1 and 83.3% of those in group 2 experienced side effects. Most of these were mild and included nausea, vomiting, diarrhea, and swelling in the feet.

This study concluded that rhG-CSF combined with small-dose decitabine after allo-HSCT can reduce the occurrence of relapse in patients with HR-AML. 

This study had a small number of participants. Also, the participants knew in which group they were. This might have influenced the results.