Feb. 18 (Bloomberg) -- U.S. regulators didn't inspect a Chinese plant that makes an ingredient tied to life-threatening side effects with the blood-thinner heparin because they mixed up records on that facility and another with a similar name.

Regulators mistakenly referred to inspection records for a plant from another company and cleared the heparin facility without necessary inspections and evaluations, said Joseph Famulare, deputy director at the Food and Drug Administration's Center for Drug Evaluation and Research.

The FDA will begin inspecting the plant this week, the agency said today in a conference call with reporters. On Feb. 11, the FDA said use of heparin in multi-dose vials made by Deerfield, Illinois-based Baxter International Inc., had been tied to dangerously low blood pressure, vomiting and difficulty breathing. Four patients taking the drug died, the agency said.

``To date this is an isolated situation, but the wrong firm was put into database, therefore this one was not evaluated or scheduled for inspection,'' Famulare, who works with the FDA centers' compliance office, said on the call today. ``We're acting upon that by doing our immediate inspection. We're looking at this process, and we have not found any other firms in this category.''

Authorities are urging doctors to use non-Baxter vials of heparin. Baxter, which had about half the U.S. market, agreed last week to temporarily halt making heparin in multiple-dose vials associated with the side effects. Used by millions of people, heparin generates about $30 million in annual sales for Baxter, which reported $11.3 billion in revenue for 2007.

APP Product Unaffected

APP Pharmaceuticals Inc., based in Schaumburg, Illinois, has the other half of the U.S. market for heparin sold in vials. APP's supplier in China has passed inspections, and its vials haven't been linked to the same adverse reactions, FDA said.

``We don't know what is causing these adverse events,'' said Michael Rogers, director of the FDA's Division of Field Investigations, during the call. ``The agency considers this as one of its top priorities and is dedicating all appropriate resources to this investigation.''

Bart Stupak, a Democratic representative from Michigan, last week criticized the FDA for failing to inspect the plant in China. The agency conducts annual inspections of about 7 percent of overseas drugmakers that ship to the U.S., a pattern suggesting the FDA would take 13 years to visit them all, according to the Government Accountability Office, the investigative arm of Congress.

All suppliers of active drug ingredients shipping to the U.S. are required to be approved by the FDA by passing physical inspections and evaluations, Famulare said. If a foreign facility has recently passed an inspection, it's not always necessary to conduct another for a new application, he said.

Baxter gets the ingredient for heparin from Scientific Protein Laboratories Inc., a U.S. company that makes the product both in the U.S. and China, according to the FDA and Erin Gardiner, a spokeswoman for Baxter.

Changzhou, China

The plant is located in Changzhou, China, about two hours drive west of Shanghai, Gardiner said in a telephone interview today. Waunakee, Wisconsin-based Scientific Protein was bought by New York-based private equity firm Arsenal Capital Partners LP from Wyeth in 2004.

The FDA is also inspecting and investigating Baxter's Cherry Hill, New Jersey, facility, and Scientific Protein's plant in Waunakee, Rogers said. Baxter is also conducting its own inspections of its supplier's plants in China and the U.S., Baxter's Gardiner said today.

``We continue to advise doctors and other health-care providers to seek alternative sources of heparin,'' said Karen Riley, an FDA spokeswoman, on today's call. ``If they cannot, they should be cautious when administering the Baxter product to their patients.''

To contact the reporter on this story: Beth Jinks in New York at bjinks1@bloomberg.net

Last Updated: February 18, 2008 15:27 EST