Indobufen treatment in type IIA hypercholesterolemic subjects: effects on platelet function and malondialdehyde production

Indobufen, an inhibitor of platelet aggregation, or a matching placebo were administered (200 mg b.i.d. by oral route) to 8 hypercholesterolemic subjects and to 8 normal volunteers, according to a randomized cross-over design for three days with a four day interval. Platelet aggregation and malondialdehyde (MDA) production by platelets were measured before and during treatment. Indobufen administration completely suppressed the aggregation of platelets induced by threshold concentrations of arachidonic acid, as well as the second wave of aggregation induced by epinephrine, up to twelve hours from drug treatment. MDA production was also completely suppressed by Indobufen administration. Platelets from type IIA patients needed lower concentrations of aggregating agents, to overcome the inhibitory effect of Indobufen.