PURPOSE: Not all venous thromboembolism (VTE) patients can tolerate warfarin because of its side effects or the inability to maintain a stable and therapeutic INR. Therefore, we tested the efficacy and safety of VTE monotherapy with fondaparinux, an anti-thrombotic agent with specific anti–factor Xa activity which provides a simple, fixed dose, subcutaneous once daily alternative in these patients.
METHODS: In this prospective cohort study, 30 patients, intolerant of warfarin therapy, with a history of deep vein thrombosis and/or pulmonary embolism were treated with fondaparinux as monotherapy without warfarin for 90 days. The primary endpoints were recurrent venous thromboembolism and major bleeding events. The secondary endpoints included measurements of hematocrit, platelet count, blood urea nitrogen, creatinine, alanine aminotransferase, and aspartate aminotransferase on study days 0, 45, and 90. These laboratory values were evaluated with a general linear model (GLM) procedure and tested against a Bonferroni adjusted significance level for multiple comparisons.
RESULTS: Of the 30 patients enrolled, 18 (60%) were female and 12 (40%) were male. The patients had a mean age of 50.2 years SD + 13.7. Patients had extensive histories of VTE and thrombophilia: 16 (53.3%) patients had a history of recurrent VTE and 13 (43.3%) patients had been previously diagnosed with a hypercoagulable state. 3 (6.7%) patients had a history of metastatic cancer. At the end of the 90 day study period, there were no recurrent venous thromboembolic events or major bleeding complications and no significant changes in hematologic measurements, renal function, or hepatic function.
CONCLUSION: Fondaparinux monotherapy appears to be safe and effective in the treatment of VTE. It provides a simple regimen consisting of a once-daily, fixed dose injection without drug-food interactions or laboratory coagulation testing.
CLINICAL IMPLICATIONS: Fondaparinux provides an important potential treatment option in patients who cannot be safely or effectively anticoagulated with warfarin.
DISCLOSURE: Ranjith Shetty, No Financial Disclosure Information; No Product/Research Disclosure Information