This is a randomised multicentre phase III clinical trial done by the Blood and Marrow Transplant Clinical Trial Network to investigate the best graft-versus-host disease prophylaxis platform used before matched donor transplant in the reduced intensity conditioning setting in patients with malignant haematological disease in need of peripheral blood stem cell transplant.

What was the methodology used?

We randomised 1:1 eligible patients with blood cancers to receive either the standard combination of methotrexate tacrolimus or the novel competitor of post-transplant cyclophosphamide, MMF and tacrolimus combination and included more than 200 patients in each arm. Patients were followed for a year at least and primary outcome was reported as GRFS which in layman terms means living with no cancer and no CVR GVHD.

What were your findings?

This large randomised multicentre clinical trial was successful and has met its endpoint. Patients who underwent the investigational arm of post-transplant cyclophosphamide MMF and tacrolimus did better significantly with lower rates of CVR graft-versus-host disease leading to better one year GRFS with a significant difference of 53% versus 35%.

What is the clinical impact of these results?

The study will provide strong evidence of superiority of the post-transplant cyclophosphamide based platform for GVHD prophylaxis. Longer follow-up will be probably important to show the impact of this new therapy on overall survival. This probably will change the standard of care and practice in the US in the choice of graft-versus-host prophylaxis in patients undergoing reduced intensity transplant with malignant blood cancers.