The World Health Organization will discontinue its trials of the malaria drug hydroxychloroquine and combination HIV drug lopinavir/ritonavir after they failed to reduce mortality in hospitalised Covid-19 patients.

The setback came as the WHO also reported more than 200,000 new cases globally of the disease for the first time in a single day. The United States accounted for 53,213 of the total 212,326 new cases.

"These interim trial results show that hydroxychloroquine and lopinavir/ritonavir produce little or no reduction in the mortality of hospitalised Covid-19 patients when compared to standard of care.

"Solidarity trial investigators will interrupt the trials with immediate effect," the WHO said in a statement, referring to large multi-country trials it has been leading.

The UN agency said the decision, taken on the recommendation of the trial's international steering committee, does not affect other studies where those drugs are used for non-hospitalised patients or as a disease prevention measure.

Another branch of the WHO-led trial is looking at the potential effect of Gilead's antiviral drug remdesivir on Covid-19. The European Commission yesterday gave remdesivir conditional approval for use after it was shown to shorten hospital recovery times.

WHO director-general Tedros Adhanom Ghebreyesus told reporters yesterday that nearly 5,500 patients in 39 countries had been recruited so far into its clinical trials and that interim results were expected within two weeks.