Stability of filgrastim and epoetin alfa in a system designed for enteral administration in neonates.
OBJECTIVE
To determine the stability of recombinant granulocyte colony-stimulating factor (rG-CSF, filgrastim) and recombinant erythropoietin (rEpo, epoetin alfa) in a solution designed for enteral administration in the neonatal intensive care unit.


METHODS
Filgrastim and epoetin alfa were added to a solution with NaCl 0.9%, sodium acetate, potassium chloride, and human albumin in concentrations designed to mimic human amniotic fluid. Additionally, the solution was dripped through polyvinyl chloride feeding tubes to simulate feedings, and aliquots were collected before, during, and after priming of the tube. Other aliquots were either frozen immediately, stored at room temperature, or refrigerated for 0, 6, 12, 18, and 24 hours.


METHODS
Filgrastim and epoetin alfa concentrations in the various aliquots were compared with the concentrations in the original solution.


RESULTS
Filgrastim and epoetin alfa concentrations were stable for at least 24 hours when refrigerated and for at least three weeks when frozen. At room temperature, filgrastim was stable for 18 hours and epoetin alfa for 24 hours. Filgrastim concentrations did not vary significantly before, during, or after priming of the feeding tube, whereas epoetin alfa concentrations decreased significantly unless the feeding tube was primed with 10 mL of solution.


CONCLUSIONS
Filgrastim and epoetin alfa were stable in our amniotic fluid-like solution. In this respect, our solution is suitable for enteral administration to patients in the neonatal intensive care unit.
Calhoun
D A
DA
Department of Pediatrics, College of Medicine, University of Florida, Gainesville 32610, USA. calhoda@peds.ufl.edu
Juul
S E
SE
McBryde
E V
EV
Veerman
M W
MW
Christensen
R D
RD
D003080:Cold Temperature; D004355:Drug Stability; D004358:Drug Therapy; D020345:Enterocolitis, Necrotizing / Q000188:drug therapy; D004797:Enzyme-Linked Immunosorbent Assay; D000069585:Filgrastim; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage* / Q000627:therapeutic use; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007363:Intensive Care Units, Neonatal; D019259:Lamivudine / Q000008:administration & dosage* / Q000627:therapeutic use; D011994:Recombinant Proteins
D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D019259:Lamivudine; D000069585:Filgrastim