Heparin Contaminant Not Naturally Produced

The contaminant identified in recalled lots of heparin, an oversulfated chrondroitin sulfate with a tetrasulfated disaccharide repeat, has not been isolated to date from animal tissues, according to data published online yesterday in Nature Biotechnology. Investigators suggest that the contaminant was, therefore, intentionally introduced into the product.

Other important information from the article:

• Synthetic tetrasulfated disaccaride repeat units of chondroitin sulfate exhibit antithrombin activity, which probably explains how the contaminated heparin passed an activity screen, such as a whole-blood coagulation test.
• The contaminant is structurally identical to Arteparon,* an intramuscular drug that was marketed in Europe for the treatment of individuals with degenerative joint disease. Arteparon has been shown to induce an allergic-type response and was withdrawn from the market because of patient deaths, most likely due to thromboembolic complications.

*As far as I can tell, Arteparon is identical to Adequon, which is marketed by Novartis for canine arthritis and by Luitpold for equine joint disease.