WASHINGTON - Baxter International Inc. has found signs of a possible contaminant in the recalled blood thinner heparin that caused hundreds of serious side effects -- further pointing suspicion at ingredient suppliers in China.
Baxter stressed Wednesday that neither it nor government investigators yet know what is to blame for the reactions.
But Baxter's high-tech testing of batches of the problem drug found signs of what it called a "heparin-like molecule" -- a substance not found in batches of problem-free heparin.
Baxter said that means the problems may have originated with Chinese suppliers of heparin's main ingredient, derived from pig intestines.
The Food and Drug Administration last week found quality-control problems at a Chinese supply factory, a factory that the agency had never before inspected, in violation of its own rules, because of a mix-up with the company's name.
But that factory in turn receives crude heparin from numerous smaller suppliers, or "workshops," complicating the search for answers.
Heparin injections are used to prevent blood clotting mostly in patients undergoing dialysis and heart surgery. Baxter, which provides about half the nation's supply, halted production last month after its brand was linked to hundreds of reports of allergic-style reactions, including vomiting, nausea and difficulty breathing.
The FDA last week said four deaths so far are associated with the recalled Baxter product, among 21 total reports of deaths among patients taking heparin from any manufacturer.
Baxter said Wednesday that FDA inspectors had found no problems at its New Jersey factory that conducts the last steps in heparin production.
