Contaminated heparin has been traced to Chinese production factories
HEALTH OFFICIALS in several countries are investigating dozens of deaths in the United States and Germany from tainted batches of the blood thinner heparin that contained an active pharmaceutical ingredient from China.
China is the world's biggest supplier of heparin ingredients, and the production of the drug is largely carried out by thousands of family workshops which gather and treat the raw material from the mucous membranes in pig intestines. The drug is commonly used to treat victims of heart attacks, as well as in dialysis and in many types of surgery.
FDA officials have said the contaminated batches came from factories in China that make the drug for US-based Baxter International, which recalled its heparin in February after deaths were reported.
Since January 2007, 81 people given heparin have died after suffering allergic reactions, the US Food and Drug Administration said. Recalls or warnings about heparin have also been issued in Australia, Switzerland, Germany, Italy, Denmark and Japan.
The FDA has identified the toxic substance in the anticoagulant drug as a synthetic compound called oversulphated chondroitin sulfate (OSCS), which is cheaper to produce than the actual drug, and there have been suggestions that fake drug manufacturers have become involved in the process, although the FDA says it had no evidence to back up this view.
Health regulators in China have stepped up supervision of the production of heparin as a precaution after a sharp rise in the reported number of deaths from allergic reactions.
Chinese industry is still reeling since damaging revelations about poor-quality manufacturing and reports of counterfeit pharmaceuticals hit the market last year, and it has been keen to be seen to be proactive on ensuring product safety and is highly sensitive to criticism about production standards.
A Chinese official this week disputed assertions that the blood thinner had caused deaths, but conceded that heparin produced in China contained a contaminant. Chinese companies have also supplied contaminated heparin to Australia, Canada, China, Denmark, France, Germany, Italy, Japan, the Netherlands and New Zealand.
More than one million multi-dose vials of heparin are sold per month in the United States, according to the FDA. Half of them are manufactured by Baxter.
About 350 adverse events associated with Baxter products have been reported since the beginning of the year, compared with less than 100 for all of 2007.
Most incidents occurred at blood dialysis centres with patients taking a high dose, administered over a short period of time, the FDA reported.
In a report carried by China's official news agency Xinhua, the health ministry said raw heparin produced and exported by some companies in China was involved, and requested medical facilities around the country to strictly check the medicine they sourced and ensure the origin could be traced later.
They said doctors had been told to strictly follow relevant regulations when applying heparin products to ensure safety and were told to closely observe patients receiving treatment with heparin.
Typical symptoms of a reaction to heparin include lip swelling, nausea, vomiting, sweating, shortness of breath and sometimes severely low blood pressure, the report said.
The US drug agency has defined suspicious deaths as those involving one or more of these allergic reactions or a drop in blood pressure.
There have been no reports of deaths since the end of February, after Baxter recalled heparin made with ingredients from a Chinese supplier.
Baxter International chief executive Robert Parkinson said last week that he did not expect issues with the recalled heparin to trigger major legal troubles, despite the high-profile problems with the drug.
It was hard to find definitive links between drug troubles and deadly reactions and that Baxter doesn't expect "any kind of material patient litigation" due to the recall.
"The fact that someone reports an adverse event does not mean a specific drug caused an adverse event," Parkinson said.
Most of the active ingredients in the drug came from a plant in Changzhou, majority owned by Wisconsin-based Scientific Protein Laboratories, which supplies Baxter as part of an outsourcing deal.
On February 28th, Baxter recalled all of its heparin from the US market, and health authorities ordered a halt on all imports of heparin blood thinners in order to test them for contaminants.
The FDA has also been co-operating with health authorities in Germany and Japan, where pharmaceuticals have recalled apparently contaminated heparin products linked to allergic reactions.
Germany's Rotexmedica was the first to pull heparin from the market, after about 80 severe allergic reactions were reported by patients who had been given the drug since February 14th - a much higher number than usual. The product was made in Germany but the active pharmaceutical ingredient was linked to two Chinese suppliers.