Ken Frazier, one of the most prominent African Americans in corporate America, will step down as Merck chief executive at the end of June, the drugmaker announced Thursday.

Frazier will stay on the board as executive chairman during a transition period, the length of which is to be determined, Merck said in a press release.

Succeeding Frazier as chief executive will be Robert Davis, who will become president on April 1 and then CEO and a board member on July 1. Davis joined Merck as chief financial officer in 2014 after stints at Baxter International and Eli Lilly.

The Philadelphia-born Frazier, 66, joined Merck in 1994, became general counsel in 1999 and then chief executive in 2011. He has been at the helm as Merck became a leader in cancer treatment with its Keytruda drug.

Ken Frazier will step down as chief executive of Merck at the end of June
Ken Frazier will step down as chief executive of Merck at the end of June GETTY IMAGES NORTH AMERICA / WIN MCNAMEE

Frazier spoke out against racial injustice following the police killing of George Floyd last May, calling on other executives to address the opportunity gap in the United States that afflicts the Black community.

"What the African American community sees in that videotape is that this African American man, who could be me or any other African American man, is being treated as less than human," Frazier told CNBC.

He also called out Donald Trump's equivocations over white supremacy in August 2017 after the former president praised extremists following a violent demonstration in Charlottesville, Virginia.

Frazier stepped down from a White House manufacturing advisory council in the wake of that incident, leading to a quick exodus of other executives and to the dissolution of two of Trump's corporate panels.

In December, Frazier, along with former IBM Chief Executive Ginni Rometty, former American Express Chief Executive Ken Chenault and others launched OneTen, which aspires to "upskill, hire and promote one million Black Americans over the next 10 years."