Single-dose granulocyte colony-stimulating factor concomitant with multifractionated dose chemotherapy: A strategy for maintaining dose intensity

Multifractionated dosing (MFD) schedules for chemotherapy administration su ch as weekly or twice weekly administration are intended to maximize dose i ntensity while minimizing toxicity, but the cumulative drug effect may resu lt in neutropenia necessitating interruption of dose fractions and thereby compromising dose intensity. Intermittent granulocyte colony-stimulating fa ctor (G-CSF, Neupogen(R), Amgen) was administered to patients receiving MFD oil three paclitaxel-based chemotherapy regimens. Single-dose G-CSF was ad ministered concomitant with the chemotherapy dose fraction when the white b lood count was between 2000 and 3500 cells/mu l. A retrospective analysis o f the concomitant administration of single-dose G-CSF with chemotherapy in these trials demonstrated that in most patients, G-CSF administration guide d by the level or grade of leukopenia permitted maintenance of the chemothe rapy dose intensity and completion of the treatment cycle. The common patte rn in a six-dose, twice weekly, multifractionated cycle was for G-CSF to be administered with every other chemotherapy dose beginning with the third, fourth, or fifth dose, but some courses required G-CSF administration with each chemotherapy dose fraction. Guidelines for the concomitant use of G-CS F and paclitaxel-based MFD chemotherapy call be used to maintain chemothera py dose intensity. A prospective study of guidelines for cytokine usage dev eloped on the basis of this retrospective study will be necessary to determ ine the optimal cytokine dose and schedule for use simultaneously with chem otherapy.