Four years after US drug-maker Baxter International’s blood thinner heparin was contaminated in China, causing dozens of deaths, lawmakers urged the FDA to prevent another heparin scare, during a recent hearing at the U.S. House of Representatives.
Therefore, US regulators issued draft guidelines to ensure the safe production of the blood-clot prevention.
“We’re making sure we have systems in place to prevent that particular problem,” FDA Commissioner Margaret Hamburg told members of Congress.
Heparin, a blood thinner used by millions of patients during kidney dialysis and heart surgery to prevent blood clots, is normally produced from pig intestines.
The FDA began receiving reports in early 2008 of serious reactions, including some deaths, among some patients undergoing dialysis and traced the problem to heparin, which is injected.
An FDA probe found a contaminant in batches of heparin from Baxter International Inc, a major supplier to the U.S. market, and determined the contaminant was a substitute synthetic compound called oversulfated chondroitin sulfate (OSCS), from China, had caused the toxic reactions. The contamination sparked congressional hearings and concerns about the lack of inspections of foreign facilities.
Chinese officials rejected the FDA’s conclusions, saying the chemical had nothing to do with the allergies and deaths, but the FDA began testing heparin imports for OSCS in 2008 to assure safety of the drug stocks.
The draft guidance, posted on the FDA website, is designed to help manufacturers of active ingredients, finished products and others better control heparin to avoid contamination.
According to the guidance document, contamination involving the chemical at issue – oversulfated chondroitin sulfate (OSCS) – appears intentional to save costs.
“OSCS contamination of heparin appears to be an example of intentional adulteration, and has also been referred to as economically motivated adulteration – i.e., heparin appeared to be intentionally contaminated with OSCS to reduce the cost of production,” the FDA said.
The new guidelines are directed toward companies who use crude heparin to manufacture drugs and medical devices, and aim to “provide additional clarification to questions and inquiries received from industry,” an FDA spokeswoman said.
The regulatory agency “continues to monitor and sample incoming heparin,” she added.
The agency’s recommendations included testing for the species origin and the presence of OSCS in each shipment of crude heparin before manufacturing. Heparin manufacturers should also audit their suppliers, the agency said.
“Substitution of non-porcine sources of crude heparin raises concerns,” said the FDA guidelines, particularly due to the risk of mad cow disease, or bovine spongiform encephalopathy, infiltrating products.
“The control of the animal origin of crude heparin is critical to ensure the safety of drugs and devices that contain heparin and to protect public health.”
The guidance is a set of recommendations and does not establish legally enforceable responsibilities. FDA will solicit comments on the document for 60 days.