UPDATE 1-Sanofi's Lantus drug no cause for concern -EU agency

The European Union's drug watchdog cast further doubt on recent studies suggesting a possible cancer risk with Sanofi-Aventis's (SASY.PA) widely-used Lantus diabetes drug.

The European Medicines Agency said in a statement on Thursday its experts concluded that the available data does not provide a cause for concern and changes to how the drug should be prescribed were not necessary.

It also called on the French drugmaker to generate further research on the drug.

"Due to methodological limitations the studies were found to be inconclusive and did not allow a relationship between insulin glargine and cancer to be confirmed or excluded," the agency said in a statement, referring to the drug's generic name.

"In addition, the committee noted that the results of the studies were not consistent."

"This is important and reassuring information for patients receiving Lantus," said Jean-Pierre Lehner, the group's chief medical officer, adding the review confirmed Lantus use should continue unchanged.

Sanofi said it would take steps to develop further research in the area, in line with recommendations made recently by an independent panel.

The guidance came after the U.S. Food and Drug Administration earlier this month questioned four recently published studies over the cancer link, saying they did not track patients long enough to properly evaluate any such risk from the drug.

Sanofi has firmly stood behind its long-acting insulin medicine Lantus seen as a medicine able to offset a fall in sales of other products, such as Plavix and Lovenox, which could soon face generic competition.

Its stock dived last month when worries about a possible but uncertain link with cancer first surfaced.

he drugmaker said at the time the data was of "poor quality" and no firm conclusions could be drawn. A group of independent experts invited by Sanofi to review the studies later concluded the studies were flawed.

Lantus had sales of 2.45 billion euros ($3.5 billion) in 2008 and had been expected to continue to grow strongly, reflecting the growing incidence of diabetes worldwide.

The last big safety scare over a diabetes drug involved GlaxoSmithKline's (GSK.L) pill Avandia, linked to heart attack risk in a U.S. study in 2007. Glaxo contested those findings, but sales of the drug still halved.

Sanofi shares rose after the announcement and closed up 1.2 percent at 46.31 euros. (Reporting by Michael Kahn; Addition Reporting by Helen Massy-Beresford; Editing by David Cowell and Dan Lalor) ($1 = 0.7030 euro)