Recombinant GM-CSF in patients with poor graft function after bone marrow transplantation

Poor graft function after bone marrow transplantation is an infrequent complication that is fatal for most patients secondary to severe infections or to bleeding. Even a second marrow infusion is usually not successful in restoring hematopoiesis. We treated nine patients with recombinant Escherichia coli derived human granulocyte-macrophage colony-stimulating factor (GM-CSF) for delayed engraftment or graft failure after autologous (n = 6) or allogeneic (n = 3) bone marrow transplantation (BMT). Six patients were given a dose of 10 micrograms/kg/d over 30 min; three patients received lower doses of 3-5 micrograms/kg/d. Seven patients lived longer than 3 days after commencing GM-CSF and could be evaluated for their response. Six of them had a marked rise in neutrophil counts; there was no effect on platelet and reticulocyte counts. Two patients died within the first 3 days after starting GM-CSF, although both seemed to have some response to GM-CSF (increasing blood neutrophils in one, and increasing macrophages in the bone marrow on autopsy in the other). Side effects most likely attributable to GM-CSF administration were mild and included diarrhea and abdominal pain, low grade fever and mild rash. Severity of graft-vs-host disease (GVHD) was not enhanced in the recipients of allogeneic marrow. We conclude that recombinant GM-CSF can be safely given to patients with poor graft function after marrow transplantation. In some patients, this may lead to a subsequently sustained neutrophil recovery.