US lawmakers cite unusual finding from Vytorin probe

WASHINGTON, April 11 (Reuters) - Two top Democrats investigating why Schering-Plough Corp (SGP.N: Quote, Profile, Research) and Merck & Co's (MRK.N: Quote, Profile, Research) delayed the release of data on their cholesterol drug Vytorin said their probe has uncovered "some unusual circumstances" and is far from over, according to a letter released on Friday.

U.S. House of Representatives Energy and Commerce Committee Chairman John Dingell and Rep. Bart Stupak, chairman of the oversight and investigations subcommittee, said they "continue to have serious concerns regarding the conduct and reporting" of the drugmakers' controversial trial, called Enhance.

In a letter to the companies' top executives, the Michigan Democrats ask the drugmakers to provide the committee with more information on various meetings and marketing issues. (Reporting by Susan Heavey; Editing by Brian Moss)