Clinical pharmacokinetics of tirofiban, a nonpeptide glycoprotein IIb/IIIa receptor antagonist: comparison with the monoclonal antibody abciximab.

Tirofiban is a nonpeptide tyrosine derivative that antagonises platelet glycoprotein IIb/IIIa (GP IIb/IIIa) receptors. It is one of three GP IIb/IIIa antagonists approved by the US Food and Drug Administration for the treatment of patients with acute coronary syndromes. The clinical effect of tirofiban has been shown in large studies such as PRISM (Platelet Receptor Inhibition for Ischemic Syndrome Management), PRISM-PLUS (PRISM - Patients Limited by Unstable Signs and Symptoms) and RESTORE (Randomised Efficacy Study of Tirofiban for Outcomes and Restenosis). Tirofiban is administered as an intravenous infusion. Volume of distribution ranges from 21 to 87 L, and binding to human plasma proteins is modest at 64%. Metabolism in humans is negligible, and most drug is excreted renally with systemic clearance ranging from 4.8 to 25.8 L/h. Renal function may influence the excretion of tirofiban, but concurrent disease or other drugs generally used in patients with ischaemia seem not to do so. This review updates what is known about the pharmacokinetics of tirofiban in humans, especially in comparison with the monoclonal antibody against the IIb/IIIa receptor, abciximab.