Ex-leaders, Nobel winners urge US to back India's Covid vaccine waiver plea Ex-leaders, Nobel winners urge US to back India's Covid vaccine waiver plea Former leaders and Nobel Prize winners called on US President Joe Biden to back a waiver of intellectual property rules for Covid-19 vaccines as proposed by India and South Africa. advertisement US President Joe Biden (Photo: Reuters) More than 60 former heads of state, including former leaders of Britain and France, and over 100 Nobel Prize winners called on US President Joe Biden to back a waiver of intellectual property rules for Covid-19 vaccines as proposed by India and South Africa.