Selective factor Xa inhibition with fondaparinux: from concept to clinical benefit

Fondaparinux (Arixtra®) is a synthetic selective indirect inhibitor of activated factor X. Administered subcutaneously, the onset of action of fondaparinux is rapid, half of the maximum plasma level being reached within 30 min after injection. Furthermore, the pharmacokinetic and safety profile of fondaparinux allows once-daily subcutaneous administration without any laboratory monitoring, including platelet count. Fondaparinux exhibits a very positive benefit-risk ratio in the prevention of venous thrombo embolism in both surgical and acutely ill medical patients at risk of thrombosis. Its favourable efficacy and safety have also been demonstrated in the initial treatment of symptomatic deep-vein thrombosis and pulmonary embolism, and in patients with non-ST and ST elevation acute coronary syndromes. This review summarizes the data obtained in all phase III clinical trials with fondaparinux in the prevention and treatment of thrombo embolic disorders.