Two pilot studies carried out by two medical teams in China found that infusions of antibody-rich plasma from recovered Covid-19 patients, known as covalescent plasma (CP), caused striking improvements in people still suffering with the viral disease.

One pilot in Shenzhen allowed three of five patients treated with an infusion with CP to be weaned off mechanical ventilation and four recovered from associated acute respiratory distress syndrome. A second pilot in Wuhan of 10 patients saw rapid and significant improvement in symptoms following a CP transfusion; these results were published on 6 April.

These results would need confirmation in a randomised clinical trial of more patients. UK researchers, led by Prof David Tappin at the University of Glasgow, are planning to do just that, they are just waiting approval from the UK’s National Institute of Health Research, as reported by the Guardian at the end of March.