title: The tolerability and pharmacology of interleukin-6 administered in combination with GM-CSF or G-CSF in the rhesus monkey.
abstract: The tolerability and potential target organ toxicity of rhIL-6 administered subcutaneously (s.c.) with rhGM-CSF or rhG-CSF were investigated in healthy nonhuman primates. Fifteen Rhesus monkeys were randomized to receive one of the following five regimens: rhIL-6, rhGM-CSF, rhG-CSF, rhIL-6 and rhGM-CSF, or rhIL-6 and rhG-CSF. Each cytokine was administered s.c. once daily at 20 micrograms/kg/day for 30-31 days. Marked increases in blood leukocyte counts (predominantly neutrophils) were observed in the rhGM-CSF and rhG-CSF treatment groups, but only a mild trend toward increased WBCs was observed with rhIL-6 alone. Platelet counts increased 1.7- to 2.2-fold in the rhIL-6 and rhGM-CSF groups. All regimens were well tolerated. RhIL-6, alone or in combination with either CSF, had no significant toxic effects at the dosages tested. Minimal to moderate bone marrow hyperplasia was observed in all except rhIL-6-treated animals, which correlated well with peripheral blood increases in WBCs. RhIL-6-treated animals demonstrated increased fibrinogen concentrations and erythrocyte sedimentation rates, decreased serum albumin/globulin ratios, and increased serum alpha-2-macroglobulin concentrations. Increased synthesis of acute-phase proteins was not observed in the other groups. Combining rhIL-6 with rhGM-CSF or rhG-CSF may reduce the rhIL-6-mediated acute-phase response while maintaining the desirable hematopoietic effects of the stimulating factors.
authors.affiliation: Department of Drug Safety, Sandoz Pharmaceuticals Corporation, East Hanover, NJ 07936, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Myers
authors.forename: J T
authors.initials: JT
authors.lastname: Boyce
authors.forename: R L
authors.initials: RL
authors.lastname: Robison
mesh_terms: D000818:Animals; D001769:Blood / Q000187:drug effects*; D001799:Blood Sedimentation / Q000187:drug effects; D004338:Drug Combinations; D004353:Drug Evaluation, Preclinical; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000008:administration & dosage*; D007279:Injections, Subcutaneous; D015850:Interleukin-6 / Q000008:administration & dosage / Q000633:toxicity*; D008253:Macaca mulatta; D008297:Male; D011897:Random Allocation; D012709:Serum Albumin / Q000187:drug effects
chemical_list: D004338:Drug Combinations; D015850:Interleukin-6; D012709:Serum Albumin; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor