Efficacy and Safety of Fondaparinux in Patients With Suspected Heparin-Induced Thrombocytopenia.

Abstract

Heparin-induced thrombocytopenia (HIT) occurs in up to 5% of patients exposed to unfractionated heparin for 5 or more days. Direct thrombin inhibitors (DTIs) are currently the only Food and Drug Administration (FDA)-approved agents for the treatment of HIT. The purpose of this study is to determine whether fondaparinux is an appropriate first-line alternative anticoagulant in patients with suspected or confirmed HIT. A retrospective study was conducted by identifying all patients who received a DTI or fondaparinux during a 5 year period, August 2009-August 2014. Patients were included if they had a HIT panel/serotonin-release assay analysis (regardless of the result) and were initiated on a DTI or fondaparinux for alternative anticoagulation. The primary outcome was new, recurrent, or progressive thromboembolic event. Secondary outcomes included bleeding events, platelet count recovery, and hospital stay. A total of 1022 patients were evaluated, and 47 patients met the inclusion criteria. Twelve patients were HIT positive and 35 were HIT negative. Seven (14.9%) of the 47 patients experienced a new thrombosis, none of whom were on fondaparinux only (FONDA). There were 4 new minor bleeds, with 1 bleed as a result of being on fondaparinux. FONDA treatment resulted in a slightly shorter median duration of hospital stay compared to the DTI-only group and the DTI followed by fondaparinux group. There is a potential for cost savings with fondaparinux due to the ease of administration and availability to be given in the outpatient setting. In this small retrospective review, fondaparinux appeared similarly efficacious and safe compared to DTIs for the treatment of suspected HIT.