Phase I study of recombinant DNA granulocyte macrophage colony stimulating factor.

In this Phase I study of rh GM-CSF three patients have been entered at each of the following dose levels--0.3, 1, 3, 10 and 30 micrograms/kg/day. The mean total white cell count (x 10(9)/l) over the first ten days of rh GM-CSF rose from 11 to 14 at 3 micrograms/kg, 8 to 23 at 10 micrograms/kg and 7 to 27 at 30 micrograms/kg. Side effects included transient pyrexias after the first two infusions of rh GM-CSF and bone pains which were severe and required analgesia in two patients receiving 30 micrograms/kg and one receiving 10 micrograms/kg. No neutralizing antibodies to rh GM-CSF have been detected in the six patients tested to date. Patients are now being studied at 60 micrograms/kg/day.