Summary
RP 48740, 3-(3-pyridyl)-1H,3H-pyrrolo [1,2-c] thiazole-7-carboxamide, a specific competitive PAF-receptor antagonist in vitro, was given to 29 healthy male volunteers for 7 days. Plasma drug concentrations and exvivo PAF-induced platelet aggregation were assessed on Days 1, 4, and 7.
RP 48740 had linear pharmacokinetics after single and repeated doses. It caused stable inhibition of PAF-induced platelet aggregation in a dose-dependent manner. The effect disappeared within 24 h, even after 7 days of repeated doses.
The effect of RP 48740 displayed a sigmoidal relation to the plasma drug concentration; I50 2.3 (0.3) mg·l−1.
There were no clinical or biological adverse reactions to RP 48740 during the study.
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Pinquier, J.L., Sedivy, P., Bruno, R. et al. Inhibition of ex-vivo PAF-induced platelet aggregation by the PAF-antagonist RP 48740: relationship to plasma concentrations in healthy volunteers. Eur J Clin Pharmacol 41, 141–145 (1991). https://doi.org/10.1007/BF00265907
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DOI: https://doi.org/10.1007/BF00265907