GSK Witty joined Glaxo UK in 1985 as a management trainee. He held various positions in the UK, including director of pharmacy and distribution in Glaxo Pharmaceuticals UK. He was a vice president and general manager of marketing of Glaxo Wellcome Inc., a subsidiary of GlaxoSmithKline with responsibility for strategy development, marketing execution and new product positioning. He was an economic adviser to the governor of
Guangzhou, China, from 2000 to 2002. He was appointed president, Pharmaceuticals Europe of GlaxoSmithKline plc in January 2003 In February 2009, he pledged to make a major change in the way GSK pharmaceuticals are priced, in an attempt to make vital drugs more affordable in countries with the lowest incomes. At the same time he announced that GSK would place certain
patents in a pool so that they were freely available for others in the search for new drugs. From 2010 until 2015, Witty was on the business advisory board of
David Cameron during Cameron's tenure as
Prime Minister of the United Kingdom. In October 2012, it was announced that he had been appointed the chancellor of the University of Nottingham with effect from 1 January 2013, having maintained strong ties with the university since graduation. Witty announced his retirement from the role of chancellor in November 2017. In July 2013, the People's Republic of China announced that they were investigating allegations of fraud perpetrated by GSK going back to 2007 and involving billions of Chinese
renminbi. Witty stated "It appears that certain senior executives in the China business have acted outside our processes and controls to both defraud the company and the Chinese health care system. To see these allegations about people working for GSK is shameful. For me personally they are deeply disappointing." From 2013 to 2015, Witty was on the
UNAIDS–
Lancet Commission for Defeating AIDS and Advancing Global Health, co-chaired by
Joyce Banda,
Nkosazana Dlamini Zuma and
Peter Piot. From 2015 until 2016, he was a member of the UN High-Level Panel on Access to Medicines, led by
Ruth Dreifuss and
Festus Mogae. In November 2015, Witty's leadership of GSK was criticised by the fund manager
Neil Woodford, who said that "he’s not doing a very good job". Woodford called for GSK to be split into four companies. In March 2016, Witty announced that he was to step down as chief executive. From 2017 until 2018, Witty led the
National Health Service’s Accelerated Access Collaborative. In July 2018, Witty became CEO of
Optum, a division of
UnitedHealth Group. In November 2019, he was named president of UnitedHealth, in addition to his role as CEO of Optum. From April 2020 to December 2020, Witty took a leave of absence from Optum to assist the
World Health Organization in developing a
vaccine for
COVID-19. In May 2020, he was appointed to the expert advisory group for the UK Government's Vaccine Task Force, chaired by
Patrick Vallance.
UnitedHealth Group Witty became CEO of UnitedHealth Group in February 2021. In April 2021, he was also appointed to the Pandemic Preparedness Partnership (PPP), an expert group chaired by Vallance to advise the
G7 presidency held by the
government of Prime Minister
Boris Johnson. In 2023, Witty's total compensation from UnitedHealth Group was $23.5 million, representing a CEO-to-median worker
pay ratio of 352-to-1 and making Witty the highest paid CEO of a US-listed health insurance company for that year. On 15 May 2024, a class action lawsuit was brought by the
City of Hollywood Firefighters' Pension Fund alleging that Witty and two other UnitedHealth Group executives were involved in
insider trading in 2023. The suit alleges that in addition to Witty,
Brian Thompson and
Stephen Hemsley sold a combined total of $120 million of UHG stock four months before shareholders and the general public were informed that the company was being investigated by the
United States Department of Justice in regard to an antitrust suit involving Optum's potential buyout of
Change Healthcare. After
the December 2024 murder of
the CEO of UnitedHealth's insurance subsidiary, UnitedHealthcare, a video was leaked in which Witty stated, "Our role is a critical role, and we make sure that care is safe, appropriate, and is delivered when people need it." The video also showed him stating that the company would continue to prevent "unnecessary care" and advising that people refrain from discussing anything with the media. Some online commenters responded with death threats, with
Fortune pointing out that UnitedHealthcare reported twice the industry average for denied claims and that "their policies contribute to medical bankruptcies and lives lost due to denied care, highlighting widespread anger at systemic issues in U.S. health care". Witty stepped down for "personal reasons" as chief executive officer of UnitedHealth Group in May 2025. ==Corporate membership==