Without identifying them, Woodcock said the five companies "represent a substantial part of the overall heparin market," and their test results and reports "will really improve our safety net."
She said any company refusing to test would trigger an FDA block of their imported heparin products at the border.
Woodcock said the FDA was also working with health authorities in Germany and Japan, where pharmaceuticals have recalled apparently contaminated heparin products linked to allergic reactions.
The FDA has not proven the contaminants are the cause of death, severe respiratory allergic reactions or lower blood pressure in patients.
Since November 2007, however, it has received reports of severe allergic reactions after a single Baxter heparin injection.
The FDA has received 785 complaints of health problems as well as 46 reports of death, but Woodcock said the initial determination linking 19 of those deaths to the Baxter drug was not certain.
In the past week, she said, there have been no reports of deaths and only two of allergic reactions from the product.
APP Pharmaceuticals Inc, another top US heparin manufacturer, has boosted production to prevent a shortage of the blood-thinner in the United States.
APP heparin tested so far is contaminant-free, FDA said.
Source-AFP
SUN/L