Bloomberg News

04/17/2008-GlaxoSmithKline PLC, Europe's largest drugmaker, failed to properly disclose studies of Avandia, the diabetes pill linked to potentially deadly side effects, U.S. regulators said.

The violations "are serious and may be symptomatic of underlying post-marketing safety reporting failures," the Food and Drug Administration said in a letter posted on its Web site. The agency said it was never told about nine studies, and an additional 11 weren't included in required annual reports from 2001 to 2007.

Avandia sales plunged last year after a May 21 report in the New England Journal of Medicine linked the drug to a 43 percent increased risk of heart attacks, prompting U.S. and European regulators to strengthen warnings on its prescribing information. The FDA found unreported research while inspecting paperwork at London-based Glaxo's offices in Research Triangle Park, N.C., from August to November, according to the letter.

"The company is not out of the woods on this one," said Jeremy Batstone-Carr, an equity strategist at Charles Stanley Group PLC. "The FDA has become extremely risk-averse and has, therefore, raised the bar for every company."

Reports of side effects prompted two of the studies, the FDA said. None of the research kept from the FDA raised new concerns about potential safety risks, company spokeswoman Nancy Pekarek said. Glaxo put in place new employee training programs after the FDA inspection to ensure that appropriate data is sent to the agency from now on, she said.

"Of the studies that were actually omitted from the FDA in any type of reporting, those studies did not show safety events," Pekarek said. "The information that the FDA needed was provided to them before" the agency changed the prescribing information.

Meanwhile, Glaxo said 247 lawsuits have been filed in the U.S. over Avandia.