Choosing a regimen for prophylaxis of graft-versus-host disease

Graft-versus-host disease (GVHD), both acute and chronic, continues to be a major problem after allogeneic haemopoietic stem cell transplantation. Combinations of pharmacological agents, such as methotrexate and cyclosporin, are most effective in patients transplanted from human leucocyte antigen (HLA)-identical related donors, but less so in patients transplanted from HLA-nonidentical or unrelated ('alternative') donors. Additional agents such as tacrolimus and rapamycin are currently being tested. The approach to T cell depletion still requires further definition, especially in regard to the prevention of leukaemic relapse. The addback of donor cells with some delay post-transplant may offer an intriguing alternative to intensified conditioning regimens for the prevention of leukaemic recurrence without necessarily increasing the risk of GVHD. All patients transplanted should be entered into well-designed studies in order to accrue data and advance our knowledge at the fastest rate possible.