China finds contaminant in heparin exports to U.S.

BEIJING (Reuters) - China has identified a contaminant in batches of blood-thinner heparin supplied by a U.S.-owned plant in China for export to the United States that has been linked to serious reactions and deaths.

It is the latest in health scares involving Chinese exports in recent months which have ranged from food and drugs to toothpaste and pet food.

China's State Food and Drug Administration (SFDA) said that the contaminant was "basically the same" as that found by U.S. health regulators in batches of Baxter International Inc's blood-thinner heparin.

The Food and Drug Administration (FDA) on Wednesday said it had identified "over-sulfated chondroitin sulfate" in Baxter's drug, and was investigating whether the chemical was purposely or inadvertently added during manufacturing in China.

Last month Baxter recalled most if its U.S. supplies of heparin, used in kidney dialysis as well as heart and other surgeries to prevent blood clots.

Chondroitin sulfate is widely sold as a dietary supplement to treat joint pain. The over-sulfated version is not know to occur naturally and therefore likely was chemically modified, an FDA official said on Wednesday.

The FDA is probing whether the contaminant is the cause of up to 19 deaths and hundreds of serious breathing problems and other reactions reported in the United States.

FDA officials said chemically manipulating chondroitin sulfate, which is widely available from animal sources, would be cheaper than getting raw heparin from pig intestines.

China's drug watchdog confirmed the contaminant had been found in batches of heparin supplied by a China-U.S. joint venture plant in Changzhou to Baxter.

The FDA on March 5 said it had found a "heparin-like" contaminant in some of the drug's active ingredient supplied to Baxter by a plant in Changzhou owned by Wisconsin-based Scientific Protein Laboratories.

The plant was "one link in a long production chain of heparin", Xinhua news agency quoted the SDFA as saying in a report on Wednesday.

Scientific Protein Laboratories earlier said a consultant working for the plant had concluded the contaminant was not linked to the plant's production but likely occurred earlier in the supply chain.

Baxter, in a statement, also said the contamination had occurred before it reached SPL.

The FDA has received 785 reports of heparin infections, including 19 deaths in patients treated with some brand of heparin. Baxter has said only four deaths may be related to its heparin and there is not enough information to say the drug was the cause.