UPDATE 1-US watchdog critical of FDA foreign drug oversight

(Adds FDA comment in paragraph 8)

By Lisa Richwine

WASHINGTON, April 21 (Reuters) - U.S. authorities increased inspections of foreign drug plants last year but still checked only a fraction of sites that supply medicine ingredients to the U.S. market, a government watchdog is set to tell Congress on Tuesday.

Concern about Food and Drug Administration oversight of foreign drug manufacturers has risen since the finding of a contaminant in some batches of blood-thinner heparin that were made with raw ingredients from China.

The Government Accountability Office will testify that the FDA increased inspections of foreign manufacturing sites to about 11 percent last year and took other steps in recent months, but made limited progress overall.

"FDA's plans represent a step forward in filling the large gaps in FDA's foreign drug inspection program, but do little to accomplish short-term change," said Marcia Crosse, health care director for the GAO, the investigative arm of Congress.

A copy of Crosse's testimony was provided to Reuters.

The FDA said on Monday it had determined the contaminant in heparin could trigger the types of sometimes-fatal allergic reactions reported in some patients treated with Baxter International Inc's (BAX.N: Quote, Profile, Research, Stock Buzz) brand of the product.

A House of Representatives subcommittee is set to question FDA Commissioner Andrew von Eschenbach about foreign drug inspections at a hearing on Tuesday where the GAO's Crosse and others also will appear.