GlaxoSmithKline's chief financial officer Simon Dingemans is planning to retire after seven years in the role.
Dingemans, who has been on the board since April 2011, will continue in his work in the company until May 2019.
A successor has not yet been appointed but the board of GSK said they are starting a global search to find his replacement.
Dingemans said: “It has been a privilege to be part of GSK and to have had the opportunity as CFO to lead many key initiatives to drive the Company forward and make it fitter for the future.”
“With the new strategy set, we have established strong foundations to deliver improved business and financial performance and I believe now is the right time for me to take this decision,” he said.
Before joining GSK, Dingemans was managing director of Goldman Sachs International and had been with the company since 1995.
Chief executive Emma Walmsley said: “Since joining GSK, Simon has played a very significant role in shaping the company. He has taken a consistent and sustained approach to support investment and improve operational efficiencies in all three of our global businesses.”