Carafiban is orally active heterocyclic peptide mimetics fibrinogen IIb/IIIa receptor antagonist with antithrombotic activity. Carafiban is a prodrug, that underwent metabolic transformation to active metabolite des-ethyl- Carafiban, that inhibited dose-dependently and reversibly human platelet aggregation. In conscious dogs, Carafiban showed a high plasma availability of the active moiety of 42±8% and a plasma half-life of 9.9 h after oral administration as measured by bioassay. Carafiban may potentially be used for chronic treatment and prophylaxis of thrombotic diseases in humans.