On Fondaparinux

Q: Fondaparinux is a unique agent used in Heparin Induced Thrombocytopenia (HIT) which can be given subcutaneously. Despite its easy method of administration what three points should be of concern when prescribing Fondaparinux for HIT? 

 Answer: Fondaparinux is a chemically synthesized version of the active pentasaccharide subunit of heparin, but it does not interact with platelet factor 4, and can be used in the management of HIT. Also, there is no need to monitor coagulation parameters. If needed, the drug level can be measured though. It can be a good agent for use on an outpatient basis. It can be used on a long term basis like in a pregnant patient. Despite its ease of use and other advantages, it is not considered the first line of treatment in HIT. The three major drawbacks with its use are 

•  long half-life of 17 hours 
•  renal excretion, and 
•  no antidote

#hematology

References:

1. Linkins LA, Dans AL, Moores LK, et al. Treatment and prevention of heparin-induced thrombocytopenia: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest 2012; 141:e495S. 

2. Warkentin TE, Pai M, Sheppard JI, et al. Fondaparinux treatment of acute heparin-induced thrombocytopenia confirmed by the serotonin-release assay: a 30-month, 16-patient case series. J Thromb Haemost 2011; 9:2389. 

3. Goldfarb MJ, Blostein MD. Fondaparinux in acute heparin-induced thrombocytopenia: a case series. J Thromb Haemost 2011; 9:2501. 

4. Mazzolai L, Hohlfeld P, Spertini F, et al. Fondaparinux is a safe alternative in case of heparin intolerance during pregnancy. Blood 2006; 108:1569. 

5. Gerhardt A, Zotz RB, Stockschlaeder M, Scharf RE. Fondaparinux is an effective alternative anticoagulant in pregnant women with high risk of venous thromboembolism and intolerance to low-molecular-weight heparins and heparinoids. Thromb Haemost 2007; 97:496.