Scientists are questioning whether waning immunity to Covid-19 could affect how useful a vaccine will be in tackling the pandemic, even as investors welcomed new positive early trial data.
A study from King’s College London, which has yet to be peer-reviewed, showed recovered patients’ antibodies declined significantly within months of infection, raising the critical issue of how long a vaccine could prevent people catching the disease.
The concerns come as shares in Moderna rose 6 per cent on Wednesday after the US biotech company shared positive data from its phase one trial showing all 45 participants had produced antibodies after receiving its vaccine candidate.