Adam Schechter, Merck's president of global human health, will step down from his position Dec. 31. He has been with Merck for 30 years.
Mr. Schechter will shift instead into an advisory role to the current CEO.
Mr. Schechter assumed the role of president of global human health in 2010. During his tenure, he strengthened Merck's ability to bring medicines and vaccines to more than 140 countries globally.
"I have relied on [Mr. Schecter's] experience and expertise as we evolved a world-class commercial organization, spanning primary care, hospital and specialty, vaccines and oncology," said Kenneth Frazier, chairman and CEO of Merck. "Because of him we are better positioned to address future opportunities and challenges as a global biopharmaceutical company, and Frank and Mike have a great foundation upon which to build future success."
Merck also made two other executive changes, promoting Frank Clyburn to COO and Michael Nally to chief marketing officer.