US Senators probe GSK over Avandia

As news about possible cardiovascular risks associated with GlaxoSmithKline's (GSK) blockbuster diabetes drug Avandia (roseglitazone) made headlines this week, two high-profile senators publicly took the drug firm to task and announced that they had begun investigations into the handling of the issue by the company and the FDA.

Senators Max Baucus (Democrat for Montana) and Chuck Grassley (Republican for Iowa), who are the chairman and ranking member, respectively, of the powerful Senate Committee on Finance, are pressing GSK "to respond to allegations that company executives sought to silence independent scientists about the risks with this particular drug."

The senators are responding to the 21 May publication of a paper in the New England Journal of Medicine suggesting that Avandia may have serious cardiovascular effects. The meta-analysis of 42 trials, conducted by researchers from the Cleveland Clinic, found that Avandia was linked to a 43 per cent increase in the risk of heart attack, as well as a major increase in the risk of death from cardiovascular causes.

The FDA issued a safety alert in conjunction with the publication of the meta-analysis, but noted that the evidence was not conclusive and that other studies had not demonstrated the increased risk.

The FDA stressed that it was not asking GSK to pull Avandia from the market or to take any other specific action related to the drug, but was instead providing the information to the public so that patients taking the drug could discuss the new data with their doctors.

However, Baucus and Grassley told the FDA in a letter released to the media that they believe the study raises serious concerns both for patients taking Avandia and for other citizens, since "American taxpayers have spent hundreds of millions of dollars on this drug through the Medicare and Medicaid programmes."

Adding another twist, the letter states that the senators believe the FDA may have known about the increased risks for some time but failed to take action. "(T)he Committee has received reports that executives with GSK met with FDA officials in October 2005 and later in August 2006 after further exploring these cardiovascular problems," the letter states. "We understand that during this same time period, other concerns were raised by FDA employees."

The letter requests that FDA Commissioner Andrew von Eschenback and other high-level FDA officials personally brief the Finance Committee regarding the issue. It also requests answers to a long list of questions regarding what the FDA knew when about Avandia, and what action it took in response.

"We need to know if this is another Vioxx, where the FDA sat on its hands and endangered lives," Grassley said in a statement released along with the letter. "The FDA has talked a good game about how it's beefed up post-market surveillance over the last two years, but a case like this undermines that claim."

The senators sent a similar letter to Christopher Viehbacher, president of US pharmaceuticals at GSK, asking for detailed timelines as well as for a slew of documents and records.

"One of the most immediate concerns to us are reports that GSK employees silenced one or more medical professionals who attempted to speak out about the potential for cardiovascular problems with Avandia," the letter adds. "This allegation is very serious and warrants further investigation."

GSK has responded strongly, issuing a statement flatly denying the allegation. "The suggestion that GSK has placed patients at risk and attempted to silence independent investigation of data is absolutely false," the firm said. "Any fair examination of the company's record will show that GSK has been fully transparent in its efforts to thoroughly study the safety and effectiveness of Avandia, and to widely communicate that information to governments, scientists, physicians, and the public in the best interests of both patients and scientific debate."

GSK said it would meet with the senators "to correct misunderstandings and to clarify the record."