Behind The Heparin Mystery: A Counterfeit Substance

Scientists investigating a mystery contaminant in the blood thinner Heparin are closing in on what they believe is a counterfeit substance, most likely made in China from animal cartilage, that was chemically altered to act like the real drug, The New York Times reports. The FDA declined to confirm the info and a spokeswoman wouldn’t comment, the paper adds.

But in interviews, Heparin experts in China and the US, including one researcher involved in the inquiry, say a chemically altered substance called over-sulfated chondroitin sulfate is probably the contaminant that the FDA believes is linked to nearly 800 serious adverse events and 19 deaths. Even so, researchers say they were not certain that the contaminant, constituting between 5 percent and 20 percent of the drug, is what is causing the allergic reactions, nor do they know precisely how or when it was mixed into the active ingredient, the Times writes.

Chondroitin sulfate is a widely used supplement to treat joint pain and in its unaltered state, doesn’t have the blood-thinning properties found in the contaminant. But scientists and researchers say the act of changing the molecule gives the substance anti-coagulating properties, according to the Times. Scientists who have examined batches of the contaminated heparin distributed by Baxter International in the US say they suspected the Heparin-like molecule was intentionally mixed into the drug.

“A child could tell you it’s counterfeiting,” Jawed Fareed, a professor of pathology and pharmacology at Loyola University Chicago, who has been studying batches of heparin since the problems with the drug were discovered, tells the paper.

UPDATE: In a teleconference this morning, Janet Woodcock, FDA’s chief of drug reviews, says it’s still not clear whether the contaminant was added by accident or was deliberate. “We can’t rule in or out whether this was accidentally or delierately introduced into the product,” she says. “What we know is we’re 99 percent sure it’s not a natural product that got into the productiono process.” And the contaminant has still not been linked to the adverse events.