The U.S. Food and Drug Administration’s (FDA) Center for Biologics Evaluation and Research posted information on its Web site on September 25, 2008, to address the use of the anticoagulant, heparin, in the manufacturing process of plasma-derived factor concentrates and in the final product. Information obtained by the FDA after canvassing product manufacturers suggests a very low risk of contamination for antihemophilic factor (factor VIII), factor IX complex concentrate, immune globulins and albumin.
The update follows reports earlier this year of severe allergic reactions and abnormally low blood pressure (hypotension) in some patients receiving intravenous injections of heparin. The incidents, which included hundreds of reactions and dozens of deaths, occurred predominantly in patients undergoing kidney dialysis, heart surgery and apheresis, removing whole blood to extract a portion of it, such as platelets. These patients receive much higher volumes of heparin than do hemophilic patients using plasma-derived products.
It was later discovered that the adverse reactions were most likely caused by oversulfated chondroitin sulfate, a heparin-like contaminant possibly added intentionally to increase the yield. The FDA eventually traced the contaminant to suppliers in China where heparin was being processed in crude, unsanitary and poorly regulated workshops.
The FDA has contacted U.S. plasma product manufacturers to learn what measures the companies were taking to reduce or eliminate potential risks of exposure to contaminated heparin. Plasma product manufacturers reported one or more of the following: heparin was not used in their products; heparin was used in early stages of manufacture and was not present in the final product; heparin used in manufacturing and in small amounts in the final product was tested and found not to be contaminated; where small amounts of heparin are in the final product, there have been no reports of an increase in allergic reactions.
With this information in hand, the agency stated, “The FDA believes the risk of adverse reactions due to contaminated heparin to patients who receive U.S. licensed plasma-derived products is likely to be extremely small.” Further, the FDA now asserts that all heparin currently used for therapeutic treatment and manufacturing in the U.S. is screened for oversulfated chondroitin sulfate using sensitive FDA screening tests.
Source: FDA update posted September 25, 2008