Former GlaxoSmithKline pharmaceutical executive Moncef Slaoui, who will serve as chief adviser on the effort to find a vaccine for the coronavirus disease (COVID-19) pandemic, speaks as U.S. President Donald Trump listens during a coronavirus disease response event in the Rose Garden at the White House in Washington, U.S., May 15, 2020. REUTERS/Kevin Lamarque

Former GlaxoSmithKline pharmaceutical executive Moncef Slaoui, who will serve as chief adviser on the effort to find a vaccine for the coronavirus disease (COVID-19) pandemic, adjusts his protective face mask after speaking as President Donald Trump holds a coronavirus disease vaccine event in the Rose Garden at the White House in Washington, U.S., May 15, 2020. REUTERS/Kevin Lamarque

Former GlaxoSmithKline pharmaceutical executive Moncef Slaoui, who will serve as chief adviser on the effort to find a vaccine for the coronavirus disease (COVID-19) pandemic, listens while wearing a protective face mask as President Donald Trump holds a coronavirus disease vaccine event in the Rose Garden at the White House in Washington, U.S., May 15, 2020. REUTERS/Kevin Lamarque

U.S. President Donald Trump passes former GlaxoSmithKline pharmaceutical executive Moncef Slaoui, who will serve as chief adviser on the effort to find a vaccine for the coronavirus disease (COVID-19) pandemic, as he removes his face mask to speak during a coronavirus response event in the Rose Garden at the White House in Washington, U.S., May 15, 2020. REUTERS/Kevin Lamarque

Former GlaxoSmithKline pharmaceutical executive Moncef Slaoui, who will serve as chief adviser on the effort to find a vaccine for the coronavirus disease (COVID-19) pandemic, adjusts his protective face mask after speaking as President Donald Trump holds a coronavirus disease response event in the Rose Garden at the White House in Washington, U.S., May 15, 2020. REUTERS/Kevin Lamarque

U.S. President Donald Trump looks on as former GlaxoSmithKline pharmaceutical executive Moncef Slaoui, who will serve as chief adviser on the effort to find a vaccine for the coronavirus disease (COVID-19) pandemic, removes his face mask during a coronavirus response event in the Rose Garden at the White House in Washington, U.S., May 15, 2020. REUTERS/Kevin Lamarque

Former GlaxoSmithKline pharmaceutical executive Moncef Slaoui, who will serve as chief adviser on the effort to find a vaccine for the coronavirus disease (COVID-19) pandemic, waits to speak as President Donald Trump holds a coronavirus disease response event in the Rose Garden at the White House in Washington, U.S., May 15, 2020. REUTERS/Kevin Lamarque

Former GlaxoSmithKline pharmaceutical executive Moncef Slaoui, who will serve as chief adviser on the effort to find a vaccine for the coronavirus disease (COVID-19) pandemic, speaks as President Donald Trump listens during a coronavirus disease response event in the Rose Garden at the White House in Washington, U.S., May 15, 2020. REUTERS/Kevin Lamarque

General view outside GlaxoSmithKline (GSK) headquarters in Brentford, following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 4, 2020. REUTERS/Matthew Childs

General view outside GlaxoSmithKline (GSK) headquarters in Brentford, following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 4, 2020. REUTERS/Matthew Childs

A box and vials of the drug Shingrix, made by GlaxoSmithKline Pharmaceutical, sit on a counter at a pharmacy in Provo, Utah, U.S. January 9, 2020. REUTERS/George Frey

A scientist studies cancer cells inside white blood cells through a microscope at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist prepares stem cells for research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist prepares stem cells for research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist prepares stem cells for research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist prepares stem cells for research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist uses a molecular weighing robot during research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist uses a molecular weighing robot during research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist prepares stem cells for research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist uses a molecular weighing robot during research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist uses a molecular weighing robot during research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist prepares stem cells for research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

Scientists look at test tubes containing stem cells at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A scientist prepares stem cells for research at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

Scientists look at test tubes containing stem cells at the GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A GSK logo is seen on a flag at a GlaxoSmithKline (GSK) research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A GlaxoSmithKline (GSK) logo is seen at the GSK research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

A GlaxoSmithKline (GSK) logo is seen at the GSK research centre in Stevenage, Britain November 26, 2019. REUTERS/Peter Nicholls

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon talks with GlaxoSmithKline's (GSK’s) new CEO Emma Walmsley (L) in GSK's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon talks with GlaxoSmithKline's (GSK’s) new CEO Emma Walmsley (L) in GSK's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's (GSK’s) new CEO Emma Walmsley tours GSK's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon talks with GlaxoSmithKline's (GSK’s) new CEO Emma Walmsley (L) in GSK's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon tours GlaxoSmithKline's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon talks with GlaxoSmithKline's (GSK’s) new CEO Emma Walmsley (L) in GSK's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

Scotland's First Minister Nicola Sturgeon talks with GlaxoSmithKline's (GSK’s) new CEO Emma Walmsley (L) in GSK's new production building in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS

GlaxoSmithKline's production building is seen in Montrose, Scotland, Britain October 22, 2018. Andy Buchanan/Pool via REUTERS