title: Comparison of the antiplatelet effect of YM337 and abciximab in rhesus monkeys.
abstract: We directly compared the effects of YM337, the Fab fragment of the humanized monoclonal antibody C4G1, on platelet aggregation and template bleeding time with those of abciximab, the Fab fragment of the human/murine chimeric monoclonal antibody 7E3, in rhesus monkeys. The duration of inhibition of platelet aggregation by abciximab after i.v. bolus injection was much longer than that by YM337. Although YM337 significantly prolonged template bleeding time at 5 min after i.v. bolus injection, this action recovered within 1 h after injection. In contrast, although abciximab also prolonged template bleeding time, the duration of this effect was sustained. In a dose-escalating continuous infusion study, we evaluated the relationship between inhibition of platelet aggregation and prolongation of template bleeding time. Platelet aggregation was inhibited by over 80% by both agents at 3 microg/kg per min, and template bleeding time was prolonged to about 30 min at 30 microg/kg per min for YM337 and 10 microg/kg per min for abciximab. Interestingly, plasma concentrations between inhibition of platelet aggregation and prolongation of template bleeding time did not overlap with YM337, but did overlap with abciximab. These results suggest that YM337 allows easier control of antiplatelet activity with less effect on bleeding time than abciximab, and has a wider therapeutic window than abciximab.
authors.affiliation: Institute for Drug Discovery Research, Yamanouchi Pharmaceutical, Tsukuba, Ibaraki, Japan. suzuki_k@yamanouchi.co.jp
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Sakai
authors.forename: N
authors.initials: N
authors.lastname: Hisamichi
authors.forename: Y
authors.initials: Y
authors.lastname: Taniuchi
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: C
authors.initials: C
authors.lastname: Terazaki
authors.forename: S
authors.initials: S
authors.lastname: Kaku
authors.forename: T
authors.initials: T
authors.lastname: Kawasaki
authors.forename: S
authors.initials: S
authors.lastname: Yano
authors.forename: O
authors.initials: O
authors.lastname: Inagaki
authors.forename: Y
authors.initials: Y
authors.lastname: Masuho
mesh_terms: D000077284:Abciximab; D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D001760:Bleeding Time; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000494:pharmacology*; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D008253:Macaca mulatta; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000097:blood / Q000494:pharmacology*; D019039:Platelet Glycoprotein GPIIb-IIIa Complex
chemical_list: D000911:Antibodies, Monoclonal; D007140:Immunoglobulin Fab Fragments; D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D000077284:Abciximab