Ridogrel, a Combined Thromboxane Synthase Inhibitor and Receptor Blocker, Decreases Elevated Plasma β-Thromboglobulin Levels in Patients with Documented Peripheral Arterial Disease^[*]

Summary

The combination of thromboxane synthase inhibition with thromboxane receptor antagonism has been shown to result in a strong inhibition of platelet aggregation and a prolongation of the bleeding time (Gresele et al., J. Clin Invest 1987;80: 1435–45).

Ridogrel is a single molecule that efficiently achieves both inhibitions in human volunteers. The present study was performed in patients with obstructive peripheral arterial disease and elevated plasma β-thromboglobulin levels. Patients were treated with either 2 × 300 mg ridogrel or 2 × 300 mg placebo per day for 2½ days, according to a double blind randomised parallel design. Plasma β-thromboglobulin decreased significantly throughout active treatment starting within 2 h after administration; serum and urinary immunoreactive TxB₂ levels and urinary 11-dehydro- TxB₂ excretion were significantly lower and serum PGE2 and 6-keto-PcF_1α levels significantly higher with ridogrel; no changes were observed in the placebo-treated group.

In conclusion this study demonstrates a reduction of platelet activation in vivo by ridogrel.

Dedicated to Professor M. Verstraete on the occasion of his 65th birthday.

• References

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