Phase I clinical studies of 7432-S: effect of 7432-S on platelet aggregation and blood coagulation

The effects of 7432-S, a new oral cephalosporin antibiotic, on platelet functions and vitamin K-dependent blood coagulation parameters were studied in human volunteers and animals. Although the ADP- and collagen-induced aggregations of human and animal platelets were inhibited in vitro by extremely high concentrations of 7432-S, the inhibitory effect of 7432-S was weaker than that of latamoxef or cefotaxime. When administered orally to human volunteers or animals, 7432-S caused no inhibition of platelet aggregation. Its administration also caused no change in prothrombin time and activated partial thromboplastin time both in human volunteers and in rats. The conclusion reached was that the new oral antibiotic 7432-S does not affect platelet functions and blood coagulation.