THURSDAY, March 6 (HealthDay News) -- German health officials reported Thursday almost 100 cases of allergic reactions to heparin, a blood-thinning drug that has been blamed for hundreds of allergic reactions and at least four deaths in the United States.

But the German version of the drug is a different brand than the heparin supplied by Illinois-based Baxter Healthcare Corp. that has been linked to the allergic reactions in the United States, primarily among dialysis patients.

Following word of the German illnesses, the U.S. Food and Drug Administration said it was urging all U.S. suppliers of heparin to start using sophisticated screening tests to see if their products are free of a contaminant that is the leading suspect in the allergic reactions linked to Baxter's medication.

Baxter gets its main heparin ingredient, which is derived from pig intestines, from China. The heparin made by the German company, Rotexmedica, of Trittau, Germany, comes from a different supplier than the one used by Baxter. No deaths have been reported in Germany, officials said.

The adverse reactions seen in Germany occurred in a dialysis center and included severe allergic reactions and shock, U.S. health officials said.

"German authorities have identified a cluster of events in a dialysis center. They also have a cluster of similar reports from doctors," Dr. Janet Woodcock, acting director of the U.S. Food and Drug Administration's Center for Drug Evaluation and Research, said during a Thursday afternoon teleconference.

"The heparin active ingredient in that [German] product is not obtained from the same source as the Baxter product," Woodcock added.

It's not yet known if the active ingredient in the German heparin came from China. And it's not known if the German heparin contains the same contaminant found in the Baxter heparin, which is supplied by Scientific Protein Laboratories, of Waunakee, Wisc.

Following Thursday's FDA teleconference, Scientific Protein Laboratories issued a prepared statement that said: "In a press briefing today, the FDA announced that the German health authorities have recalled heparin that has been associated with similar adverse event clusters as have been reported in the United States. This heparin was sourced from an API [active pharmaceutical ingredient] company other than SPL. We believe this demonstrates that the heparin problem is not within Changzhou SPL's or Baxter's manufacturing facilities, but our investigation into the root cause of the problem will continue.

On Wednesday, the FDA announced that tests had found a heparin-like contaminant in heparin blood-thinning products made by Baxter.

"While the FDA has not determined the root cause of the adverse events, we have found a heparin-like compound, which is not heparin, present in some of the active pharmaceutical ingredients produced by Scientific Protein Laboratories," Woodcock said during a Wednesday teleconference.

Ray Godlewski, vice president of quality for Baxter's medication delivery business, said "all the contaminated heparin came from China."

Scientific Protein Laboratories and its Changzhou SPL plant in Changzhou City, China, is Baxter's main supplier of the active pharmaceutical ingredient in heparin, Woodcock said.

"This contaminant is present in significant quantities in some of the active pharmaceutical ingredients, accounting for approximately 5 to 20 percent of the substance tested," Woodcock said Wednesday.

The substance reacts like heparin in the conventional tests that are used for heparin, which is why those tests of ingredients might not detect the contaminant, Woodcock said.

Heparin is a blood thinner often given to dialysis patients and people undergoing heart surgery.

Woodcock said Wednesday that the FDA hadn't uncovered a direct link between the contaminant and the adverse events and deaths. "We know that some of the suspect batches of heparin that were causing the adverse events have this contaminant in it. So there is an association between the contaminant in the presence of adverse events, but it is not a direct causal link yet," she said.

Following Wednesday's teleconference, Scientific Protein Laboratories released a prepared statement that said it was "premature to conclude that the heparin active pharmaceutical ingredient (API) sourced from China and provided by SPL to Baxter is responsible for these adverse events."

Contaminated products from China have been an ongoing worry for the FDA. If the heparin contamination turns out to be deliberate, it would be reminiscent of last year's scandal when a Chinese company was charged with adding the toxic chemical melamine to an ingredient used in U.S. pet food that killed thousands of dogs and cats. The melamine let the ingredient pass chemical inspections for protein content, the Associated Press reported.

Since the end of December, there have been 785 reports of adverse reactions associated with Baxter's heparin product. This compares with less than 100 reports of adverse reactions in all of 2007.

There also have been 46 deaths, four of which were associated with an adverse reaction to heparin, according to the FDA.

Adverse reactions included difficulty breathing, nausea or vomiting, excessive sweating and falling blood pressure, which can lead to life-threatening shock.

More information

For more about heparin, visit the U.S. National Library of Medicine .

SOURCES: March 6, 2008, teleconference with Janet Woodcock, M.D., acting director of the U.S. Food and Drug Administration's Center for Drug Evaluation and Research; March 6, 2008, prepared statement, Scientific Protein Laboratories, of Waunakee, Wisc.

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