Sanofi-Synthelabo informed that the synthetic, selective factor Xa inhibitor Arixtra (fondaparinux sodium) has been approved by the US Food and Drug Administration (FDA) for two new indications.

The treatment of acute deep venous thrombosis when administered in conjunction with warfarin sodium, and the treatment of acute pulmonary embolism when administered in conjunction with warfarin sodium when initial therapy is administered in the hospital Arixtra is already indicated in the US for the prophylaxis of deep vein thrombosis.

The file for the new indications for Arixtra was submitted to the FDA on July 31, 2003. The clinical dossier was based upon the findings of the MATISSE PE and MATISSE DVT studies which demonstrated that a new strength of Arixtra 7.5 mg given as a once daily subcutaneous injection, when administered in conjunction with warfarin sodium, can effectively and safely treat the acute phases of both deep vein thrombosis and pulmonary embolism.

The MATISSE PE study showed that a fixed once daily subcutaneous dose of Arixtra 7.5mg, without need for coagulation monitoring, appears to be at least as effective and as safe as continuous intravenous and dose-adjusted UFH.

DVT and PE represent two manifestations of the same disease known as Venous Thromboembolism (VTE), a condition in which blood clots in the lower limbs (DVT) may travel to the lungs where they can cause a PE. VTE is the third most common cardiovascular disease after heart attack and stroke. VTE affects about two million Americans annually, at least 60,000 of those who will die of PE.

As with other antithrombotics, the most common side effect during Arixtra administration is bleeding. Arixtra is contraindicated in patients with severely impaired kidney function. Arixtra prophylactic therapy is contraindicated in patients who weigh less than 50 kg (110 pounds), undergoing hip fracture, hip replacement and knee replacement surgery because they may have an increased risk for major bleeding. Patients greater than 75 years of age also may be more likely to experience major bleeding complications.