Merck said it received a subpoena related to marketing and selling activities with respect to three drugs: Temodar, PegIntron and Intron A.

The subpoena, disclosed today in a regulatory filing, requests information related to the company’s promotional activities from January 1, 2004, to the present, in “a federal healthcare investigation under criminal statutes.”

The company said it is cooperating with the Department of Justice investigation.

Global sales of Temodar, a treatment for brain tumors, were $1.07 billion in 2010. PegIntron, for treating hepatitis C, generated $737 million last year, while Intron A, marketed for chronic hepatitis B and C and numerous anticancer indications, had $209 million in 2010 sales.