Instead of adding the trial to an ongoing United State process, AstraZeneca might launch a fresh study to evaluate a lower dosage of its vaccine that performed better than a full dosage, Pascal Soriot told Bloomberg News.
“Now that we’ve found what looks like a better efficacy we have to validate this, so we need to do an additional study,” he said, adding that the new, likely global, study could be faster because it would need fewer subjects as the efficacy was already known to be high. The news comes as AstraZeneca faces questions about its success rate that some experts say could hinder its chances of getting speedy U.S. and EU regulatory approval.
Several scientists have raised doubts about the robustness of results released on Monday showing the experimental vaccine was 90% effective in a sub-group of trial participants who, by error initially, received a half dose followed by a full dose. Soriot said he did not expect the additional trial to delay British and European regulatory approvals.
Asked about the Bloomberg report, an AstraZeneca spokesman said there was strong merit in continuing to investigate the half-dose/full dose regimen. Any further insights from the data would be added to those from existing trials that are being prepared for regulatory submission, he said.
Running an additional trial might not be too much of a complication for the British drug maker in the race to develop a vaccine to help tame the pandemic, which has killed more than a million people and roiled the global economy.