Use of granulocyte-macrophage colony stimulating factor in the treatment of prolonged haematopoietic dysfunction after chemotherapy alone or chemotherapy plus bone marrow transplantation.

This study evaluates the use of granulocyte-macrophage colony stimulating factor (GM-CSF) in patients with prolonged haematopoietic dysfunction (> 21 days) after using chemotherapy to treat cancer. One hundred and seven patients were identified who had a leucocyte count below 1000 cells/mm3 more than 21 days after start of chemotherapy (81 patients) or after bone marrow transplantation (BMT)(26 patients). There were 66 males and 40 females ranging in age from 4.5 to 82 years. The duration of aplasia was 48 +/- 43 days in the chemotherapy alone group, and 79 +/- 57 days in the post BMT group. Over 80% of the patients had haematologic malignancies and 70% had an infection prior to the start of the cytokine. Patients received 5 micrograms GM-CSF/kg1 body weight daily i.v. or s.c. for 14 +/- 11 days in the chemotherapy group and 20 +/- 26 days in the BMT group. Sixty percent of chemotherapy patients and 58% of BMT patients had a haematological response to treatment (leucocyte count > 2000 cells/mm3. Median times to haematologic recovery were 7 days in the chemotherapy group and 10 days in the BMT group. There was a significant reduction in the number of infections (73% to 28% in the chemotherapy group). Clinical responses in the two groups were 55% and 50%, respectively. No severe, drug-related adverse events were reported and no evidence of stimulation of malignant clones was observed. It is concluded that GM-CSF is effective and well tolerated in patients with prolonged bone marrow dysfunction after chemotherapy or BMT. Although results from an open-label trial must be viewed with caution, this observation confirms the value and safety of GM-CSF therapy in patients with this severe, and often fatal, condition.