American pharmaceutical company Pfizer announced on Friday that its investigational Covid-19 oral antiviral candidate, Paxlovid, showed an 89 per cent reduction in hospitalisation or lethal cases in high-risk patients.

"The scheduled interim analysis showed an 89% reduction in risk of Covid-19-related hospitalization or death from any cause compared to placebo in patients treated within three days of symptom onset (primary endpoint)," Pfizer said in a statement. None of the patients who received Paxlovid died during the testing that lasted 28 days, compared with 10 deaths (1.6%) among those who received a placebo.