A U.S. wholesaler of heparin sat on a complaint of contamination for nearly a year, an FDA investigation has revealed, well after the blood-thinner was recalled in 2008 for contaminated raw materials.

According to the Wall Street Journal, which reviewed the September FDA report, Wisconsin-based wholesaler Scientific Protein Laboratories (SPL) received a complaint from a company that had detected contaminants in one of the SPL heparin lots in October 2008, but did not look into it until September 2009. When SPL did finally investigate, the Journal reports, “it found that the contaminated raw material was used in two processed batches of heparin,” but it stopped reviewing one batch in June 2010 and never investigated the second.

SPL sold batches of the blood-thinner imported from a Chinese subsidiary to Baxter International, whose heparin was linked to numerous deaths and patient injury in 2007 and 2008 from contaminants that were later discovered to have originated in Chinese plants.

“I think it is deeply concerning that even after the national recall of heparin, which had been sourced from SPL, that the company would…fail to investigate a report of contaminated heparin in a timely way,” the Pew Health Group’s Allan Coukell told FDA Week, which also reviewed the FDA report.

“This is clearly a supplier of active ingredient that should have been under a lot of scrutiny from early 2008, so it’s hard to understand why these concerns apparently aren’t identified until a 483 that was issued in 2010,” Coukell said. “It’s really ultimately the company’s responsibility to ensure that the appropriate quality standards are in place and that reports of contamination are investigated in a timely way and FDA is saying that did not happen here.”

A source for the Journal indicated that the SPL contamination complaint may have come from Momenta, a Boston-based biotech firm, which won FDA approval this summer for a generic form of the drug.

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–Kate Petersen, PostScript blogger