As confirmed by the US Food and Drug Administration on Tuesday, while there have been no direct evidences uncovered of speculations that Merck and Co's popular and high selling cholesterol drug Vytorin might increase the risk of contracting cancer, a link cannot be completely ruled out just as yet.

The FDA carefully reviewed the data on the drug in question and Zetia, another medicine from the house of Merck related to it, in a trial called SEAS, in addition to taking into data collected from two very large ongoing studies.

"Based on the currently available information, FDA believes it is unlikely that Vytorin or Zetia increase the risk of cancer or cancer-related death, but at this time an association cannot be definitively ruled out", the agency said.

In January 2008, Zetia and Vytorin were put under question when a study called ENHANCE raised concerns about the drugs' complete effectiveness. Despite the fact that sales of both these drug declined considerably after the ENHANCE data was released; they still managed to remain a franchise worth $4 Billion-a-year.

Leerink Swann analyst Seamus Fernandez stressed that although it was expected, the FDA statement has been a much positive development. The cancer concerns were "an overhang for the stock, so getting it out of the way as a potential concern is a positive. It's good from the perspective of eliminating an investor overhang", he said.