The pharmaceuticals giant, which agreed in December to merge its consumer healthcare business with Pfizer Inc’s (NYSE:PFE) rival operation, said it has started the process to find a successor to Hampton.
Hampton became chairman of GSK in May 2015, a month after being appointed as deputy chairman and four months after joining the board.
“Following the announcement of our deal with Pfizer and the intended separation of the new consumer business, I believe this is the right moment to step down and allow a new chair to oversee this process through to its conclusion over the next few years and to lead the Board into this next phase for GSK,” he said.
GSK will own 68% of the combined consumer healthcare business, which brings together products such as Panadol and Advil with combined sales of US$12.7bn.
The deal is expected to deliver cost savings and synergies of about US$650mln per year.
Further down the line, the companies plan to separately list the enlarged business, which will be named GSK Consumer Healthcare.
Glaxo shares were down 0.4% to 1,493p on Monday afternoon.
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