Walt Disney Co. executive Channing Dungey, the first African-American to lead entertainment programming at one of the big four broadcast networks, is stepping down after less than three years.

She’ll be replaced by Karey Burke, who held a similar job at Disney’s Freeform cable network. That promotion will put Burke in charge of all TV show development and casting at ABC. Dungey is staying through a transition, the company said in a statement Friday.

Dungey got the job in February 2016 following a long career in TV show development, including work with writer Shonda Rhimes on her string of hits such as “Scandal.” She has tried unsuccessfully to lead a turnaround at ABC, which is in fourth place in total viewers.

Her exit is part of a broader shake-up at Disney. The entertainment giant said recently that key executives from 21st Century Fox Inc. would lead their combined television businesses after the companies complete their $71 billion merger early next year. Ben Sherwood, Dungey’s boss, is expected to leave the company after the merger.

When the Fox deal is completed, Burke will report to Dana Walden, who will be chairman of Disney Television Studios and ABC Entertainment.