PURPOSE:Fondaparinux, a synthetic pentasaccharide antithrombotic agent, has specific anti-Xa activity indicated for venous thromboembolism (VTE) prophylaxis following orthopedic surgery and for the treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE) in conjunction with warfarin. Recent data have demonstrated the efficacy of fondaparinux for the treatment of DVT and PE as monotherapy without warfarin, for acute coronary syndrome (ACS), and in heparin induced thrombocytopenia (HIT). We initiated a single-center evaluation at Brigham and Women’s Hospital to explore the current prescribing patterns according to therapeutic indication and to assess the safety and efficacy of fondaparinux.
METHODS:Over a 30-month period, hospitalized patients more than 18 years old who received fondaparinux were enrolled in this investigator initiated, observational study. Patients were evaluated for baseline demographic data, indication for anticoagulation, fondaparinux use, 30-day all-cause mortality, 90-day rate of DVT or PE, and hemorrhagic events.
RESULTS:Overall, 219 patients were prescribed fondaparinux during the study period. The use of fondaparinux for non-FDA approved indications occurred in 166 (75.8%) patients. Fondaparinux was used for prophylaxis against DVT and PE (not following orthopedic surgery) in 164 (74.9%) patients, treatment of DVT in 27 (12.3%) patients, treatment of PE in 22 (10.0%) patients, prophylaxis against DVT and PE following orthopedic surgery in 4 (1.8%) patients, and aortic thrombosis in 2 (0.9%). Ninety-eight (44.7%) patients had documentation of HIT, and 140 (63.9%) patients were switched to fondaparinux after initiation of another antithrombotic agent. At 30 days, there were 29 (13.2%) deaths, and at 90 days, 15 (6.8%) new DVT/ PE events occurred.
CONCLUSION:Fondaparinux is usually prescribed for non-FDA approved indications at our hospital. Most patients are initiated on fondaparinux due to evidence or clinical suspicion of HIT, and many patients are switched to fondaparinux from another antithrombotic agent.
CLINICAL IMPLICATIONS:Fondaparinux warrants further evaluation in patients with HIT or suspected HIT. Our study raises the possibility that in the setting of an academic medical center, fondaparinux’s off-label use may exceed its use for FDA approved indications.
DISCLOSURE:Steven Baroletti, No Financial Disclosure Information; No Product/Research Disclosure Information