Effect of recombinant human granulocyte-macrophage colony-stimulating factor on myelopoiesis in the acquired immunodeficiency syndrome.

We administered recombinant (biosynthetic) human granulocyte-macrophage colony-stimulating factor (GM-CSF) to 16 patients with the acquired immunodeficiency syndrome (AIDS) and leukopenia (2225 +/- 614 cells per microliter [mean +/- SD]). Each patient first received a single intravenous dose; 48 hours later a 14-day continuous intravenous infusion of the agent was begun. The doses used were 1.3 X 10(3) (n = 4), 2.6 X 10(3) (n = 4), 5.2 X 10(3) (n = 4), 1.0 X 10(4) (n = 3), or 2.0 X 10(4) (n = 1) U per kilogram of body weight per day. Administration of recombinant GM-CSF resulted in dose-dependent increases in circulating leukocytes and in increases in circulating neutrophils, eosinophils, and monocytes. The peak leukocyte count ranged from 4575 +/- 2397 cells per microliter at the lowest dose, to 48,700 in the patient receiving the highest dose. Mild side effects--low-grade fever, myalgia, phlebitis, and flushing--were observed in some patients; there were no life-threatening toxic reactions. Our data demonstrate that recombinant human GM-CSF is well tolerated and biologically active in leukopenic patients with AIDS. Strategies to increase the number and function of circulating leukocytes may reduce the morbidity and mortality of infections in these and other patients with leukopenia.