After more than three and a half years in the role, Philip Hampton will step down as the Chairman of Britain's biggest drugmaker GlaxoSmithKline (GSK).

The news came up a month after Emma Walmsley, GlaxoSmithKline’s Chief Executive announced her plans to split the company into two businesses -- one for prescription drugs and vaccines, the other for over-the-counter products.

Walmsley announced in December that GlaxoSmithKline and Pfizer would combine their consumer health businesses in a joint venture with sales of $12.7 billion, 68 percent-owned by the British company, in an all-equity transaction.

Philip was appointed to the Board on 1st January 2015. He was appointed as Deputy Chairman from 1st April 2015 and as Chairman from 7th May 2015.

Philip says, “It is a privilege to serve as Chairman of GSK. It is one of the UK’s great companies and under Emma Walmsley’s leadership, GSK has made very good progress with a new strategy and new approach to R&D. 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.” 

Prior to joining GSK, Sir Philip chaired major FTSE 100 companies, including The Royal Bank of Scotland Group plc and J Sainsbury plc. He has also served as Group Finance Director at Lloyds TSB Group, BT Group plc, BG Group plc, British Gas plc and British Steel plc. Sir Philip was previously appointed an Executive Director of Lazards and a Non-Executive Director at RMC Group Plc and Belgacom SA.

The Board has started the process to find a successor, says a statement by GlaxoSmithKline.