Hi George! Would you happen to have a list of laboratories performing the anti-Xa assay for Fondaparinux (pentasaccharide, Arixtra)? Do you recommend, when calibrating the assay, to use commercially-available material or spiked normal pooled plasma (NPP)? Thanks for your help!! Love this resource that you provide!!
Crystal Azevedo, MT(ASCP)SH
Hi, Crystal, thanks for your comment. Machaon Diagnostics, Quest and LabCorp provide the assay; you can find it listed under Fondaparinux in their online catalogs. Further, you’ll probably find the assay at a nearby academic medical center or tertiary care facility. Many of the labs that offer the heparin anti-Xa assay have chosen to set it up as its use is growing and monitoring is necessary in hemorrhage or in patients with renal disease.
You can definitely spike NPP with Fondaparinux from your pharmacy, several local places are doing that successfully. Alternatively, HYPHEN BioMed distributes a set of Biophen® calibrators and controls designed to be used with their anti-Xa kit. In North American these are distributed by Aniara and are currently research use only. Stago indicates their STA®-Rotachrom assay may be used for monitoring Fondaparinux, however they do not provide calibrators or controls. If anyone has a procedure for spiking plasma with Fondaparinux that they are willing to share, please add a comment. Geo.