Tyrosine kinase inhibitor treatment after stem-cell transplant in patients with FLT3-ITD acute myeloid leukemia 

This study aimed to review existing evidence regarding the outcome of tyrosine kinase inhibitor (TKI) maintenance therapy after allogeneic stem-cell transplantation (allo-SCT) in patients with FLT3-ITD mutated (genetic abnormality) acute myeloid leukemia (AML).  

This study concluded that TKI maintenance therapy after allo-SCT was associated with improved outcomes and survival for these patients.  

AML that results from the FLT3-ITD mutation is an aggressive form of leukemia. Patients with this condition have a poorer prognosis when treated with standard therapies. One treatment option for these patients is allo-SCT. This involves transplanting stem cells (cells that can develop into any cells of the body) from a donor (commonly a sibling). However, many patients relapse after allo-SCT.

After a powerful treatment, patients can receive maintenance treatment to prevent relapse. TKIs such as sorafenib (Nexavar) and midostaurin (Rydapt) are a type of targeted therapy that shows promise in patients with relapsed FLT3-ITD mutated AML. However, it is not clear if TKI maintenance after allo-SCT in patients with AML with an FLT3-ITD mutation is effective.  

This study analyzed data from 7 studies that included 680 patients with FLT3-ITD mutated AML. All patients had a stem cell transplant followed by TKI maintenance. Five studies used sorafenib as TKI treatment after stem cell transplant and two used midostaurin. The follow-up ranged between 18 and 59 months. 

Survival without relapse was 52% higher in patients that had TKI maintenance compared to those who did not. Relapse was 65% less likely in patients treated with TKI maintenance.   and overall survival were significantly improved after TKI maintenance therapy. There was no significant difference between sorafenib and midostaurin treatment.  

Patients treated with TKI maintenance were also 52% more likely to survive compared to those who did not. 

This study concluded that maintenance therapy with TKI after allo-SCT was associated with improved outcomes for patients with FLT3-ITD mutated AML.  

The studies analyzed had different protocols. The chemotherapy used before allo-SCT was not the same. Also, the time from transplant TKI was started was not the same. This may have influenced the results.