GlaxoSmithKline said its Chief Executive Andrew Witty would retire in 2017 having held the position since 2008, prompting the British pharmaceutical company to start looking for his successor.
Witty, a 31-year company veteran, has been under fire from some investors in the past three years as sales and profits have flagged. His reputation was further tarnished by a damaging bribery scandal in China.
The CEO said it was important that the board had sufficient time to conduct the search for his replacement.
"By doing so we will strongly position GSK to achieve the medium-term outlook set out to investors last year and deliver a return to core earnings growth in 2016," Witty said in the company's statement on Thursday.