June 12 (Bloomberg) -- A U.S. senator asked regulators to determine whether GlaxoSmithKline Plc, the world's second-largest drugmaker, withheld data linking its anxiety drug Paxil to higher risks of suicide.

Republican Senator Charles Grassley of Iowa, the ranking minority member of the Finance Committee, asked the Food and Drug Administration to review a U.K. government finding issued three months ago that London-based Glaxo suppressed the data since 1998, the senator said in a statement posted on the committee's Web site today. Glaxo earlier told Grassley the risks surfaced in 2006.

The London-based company has faced ``numerous claims and lawsuits'' in the U.S., Canada and the U.K. alleging that Paxil caused addiction and homicidal or suicidal behavior, according Glaxo's annual report. Glaxo settled cases in U.S. courts in 2006 without admitting liability. The FDA strengthened product warnings about increased risks in young adults and children.

``It looks like GlaxoSmithKline bamboozled the FDA,'' Grassley said yesterday in a Senate speech. ``We cannot live in a nation where drug companies are less than candid, hide information and attempt to mislead the FDA and the public. These companies are selling drugs that we put in our bodies, not sneakers.''

Grassley sent his inquiry after obtaining a report submitted by Joseph Glenmullen, a Harvard University psychiatry professor, as part of a lawsuit against Glaxo. In his recently unsealed report, Glenmullen says Glaxo had the evidence to disclose findings of increased suicide risks as long as 16 years ago. British authorities reached a similar conclusion.

U.K. Review

Glaxo ``could and should'' have informed the U.K.'s Medicines and Healthcare products Regulatory Agency sooner than 2003 about studies that found that patients under 18 who took the drug had a higher suicide risk, the British regulators said. The agency reviewed more than 1 million pages of evidence on Paxil, which is known as Seroxat in the U.K.

``The company rejects any suggestion that it withheld drug trial information,'' Glaxo said in a Feb. 6 statement that spokeswoman Mary Anne Rhyne sent again today responding to requests for comment.

U.K. regulators in March concluded that Glaxo should have informed them sooner than 2003 about studies showing that Paxil patients under 18 were more likely to kill themselves.

British prosecutors decided not to bring criminal charges because of weaknesses in that country's laws. In response, Health Minister Dawn Primarolo said she would propose stronger European Union and U.K. laws governing disclosure of drug safety information.

Grassley sent his request yesterday for a U.S. review to Health and Human Services Secretary Michael Leavitt and FDA Commissioner Andrew C. von Eschenbach.

To contact the reporter on this story: Avram Goldstein in Washington at agoldstein1@bloomberg.net.

Last Updated: June 12, 2008 16:07 EDT