* Consumer advocacy group asks FDA to withdraw Victoza
* Novo Nordisk says group’s claims are groundless
* Shares fall; most-traded stock on Copenhagen bourse
COPENHAGEN, April 20 (Reuters) - Danish drugmaker Novo Nordisk rejected a consumer advocacy group’s complaint about its big-selling diabetes drug Victoza as groundless and said it did not expect U.S. regulators to take any action.
Its shares initially dropped more than 2 percent in brisk trade on Friday after non-profit group Public Citizen asked the U.S. Food and Drug Administration (FDA) to withdraw approval of Victoza.
Novo Nordisk, the world’s biggest producer of insulin used to treat diabetes, was the most-traded stock on the Copenhagen bourse, with more than 350 million Danish crowns ($61.8 million) worth changing hands.
Public Citizen said on Thursday that Victoza increases the risk of serious health problems such as thyroid cancer and kidney failure.
Novo Nordisk’s Chief Science Officer Mads Krogsgaard Thomsen told Reuters on Friday that Public Citizen had referred to old data from studies on mice and rats which had no relevance to the use of Victoza in humans.
“We do not expect any consequences for Victoza from Public Citizen’s petition,” Thomsen said. “There is nothing in it.”
Novo said the FDA reviewed data from almost 4,000 patients before deciding to approve Victoza, and that doctors and patients should be confident in the drug’s safety.
Sydbank analyst Soren Lontoft said it was unlikely that Victoza would be taken off the market.
Victoza, approved in 2010, treats adults with type 2 diabetes, the most common form of the disease. It is one of Novo’s biggest sellers, with global sales of 2.1 billion Danish crowns ($370 million) in the fourth quarter of 2011.
Victoza is not an insulin but belongs to the GLP-1 category of drugs that work by stimulating insulin release in the body when glucose levels become too high.
Novo Nordisk shares pared their earlier losses to trade 1.8 percent lower at 839.50 crowns by 0941 GMT, underperforming a 1.1 percent drop in the Copenhagen bourse’s blue-chip index of 20 biggest stocks.
Jyske bank trader Martin Munk said the report of Public Citizen’s petition to the FDA was weighing on Novo Nordisk, the most valuable company on the Copenhagen bourse.
“It seems that this is being used to take some profits today from Novo Nordisk which has performed very strongly recently,” Munk said.
The stock is up nearly 27 percent this year, against a 17 percent increase in the OMXC20 index.