FDA identifies contaminant in blood thinner

FDA identifies contaminant in blood thinner

The substance wouldn't have occurred naturally in the heparin from China, the agency says, suggesting a counterfeit drug could be involved. The import may have led to the deaths of up to 19 in the U.S.

By Ricardo Alonso-Zaldivar, Los Angeles Times Staff Writer
10:19 AM PDT, March 19, 2008

WASHINGTON -- The Food and Drug Administration said today it has identified a mystery ingredient that contaminated a type of blood thinner imported from China that could have led to as many as 19 U.S. deaths and hundreds of severe allergic reactions among frail patients.

FDA Deputy Commissioner Janet Woodcock said the contaminant would not have occurred naturally in the many steps involved in processing the blood thinner heparin. That raised the possibility that a counterfeit drug could ultimately be blamed in the case.

"At this moment, we don't know whether it was introduced intentionally or by accident," she said. Officials stopped short of saying they suspected the heparin to be counterfeit, but they clearly indicated they were investigating that possibility.

FDA officials identified the contaminant as "over-sulfated chondroitin sulfate," a substance related to a nutritional supplement that can be acquired without a prescription and is sometimes taken for joint pain.

The announcement came a year after the FDA identified melamine as the chemical in pet food ingredients imported from China that sickened thousands of pets, launching a massive recall that heightened consumer concerns about a wide range of Chinese goods. The United States and China have since signed several safety agreements to raise product standards and facilitate investigations. FDA officials said the agreements made a significant difference in the heparin investigation, resulting in speedy visas for U.S. inspectors and greater cooperation from their Chinese counterparts.

Woodcock said the heparin contaminant "is not an approved drug in the United States, nor should it be present in heparin." Another FDA official said the contaminant is cheaper to produce than heparin and mimics the blood thinner in standard tests of drug potency and purity. It was only discovered after the FDA instituted more sophisticated testing after a rash of reports indicating problems.

Heparin is given to patients undergoing heart surgery or kidney dialysis to prevent the formation of blood clots that can cause strokes and heart attacks. Baxter Healthcare Corp. last month recalled multi-dose heparin vials used in hospitals and dialysis centers after the Illinois-based company noticed an unusual increase in reports of problems, including some involving patients who suffered a sudden drop in blood pressure after receiving the drug. Baxter received the heparin from a longtime supplier, Scientific Protein Laboratories of Waunakee, Wis. In turn, the supplier received heparin from a manufacturing facility in Changzhou, China, of which it is a part owner.

Heparin is a naturally occurring substance in the lining of pig intestines. China has become the world's leading supplier of heparin, partly because of its plentiful supply of pigs, but chiefly because of its low labor costs. Although Western pharmaceutical firms operating in China strive to maintain high standards, that country's famously lax regulation has proven a challenge.

The FDA has been criticized by prominent lawmakers in Congress because it failed to inspect the Chinese plant that produced the heparin before allowing it to be shipped to the United States. Someone at the agency mixed up the name of the Changzhou plant with another one that had already been inspected. A belated FDA inspection last month found a series of documentation and quality control problems that former agency officials said would have been considered serious in a U.S.-based facility. Baxter and Scientific Protein Laboratories have said the Changzhou plant operated according to rigorous standards and passed several checks by internal inspectors.

The heparin case is likely to lead to congressional investigations, and may even help propel legislation that would create a much tougher system for inspecting imports, financed with new fees on importers.

ricardo.alonso-zaldivar

@latimes.com

http://www.latimes.com/news/nationworld/nation/la-na-fda20mar20,1,5435171.story