AstraZeneca is likely to run an additional global trial to assess the efficacy of its COVID-19 vaccine candidate, its chief executive Pascal Soriot was quoted as saying on Thursday following questions over the results from the company’s late-stage study.
Instead of adding the trial arm to an ongoing U.S. process, a new study would be run to evaluate a lower dosage that performed better than a full amount in AstraZeneca’s studies, Soriot said in a Bloomberg News report.
“Now that we’ve found what looks like a better efficacy, we have to validate this, so we need to do an additional study,” Soriot was quoted in the report as saying.
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Soriot said it would probably be another “international study, but this one could be faster because we know the efficacy is high so we need a smaller number of patients.”
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 showing the experimental vaccine was 90 per cent effective in a sub-group of trial participants who, by error initially, received a half dose followed by a full dose.
At the heart of concerns is that the trial’s most promising result of 90 per cent comes from a sub-group analysis — a technique many scientists say can produce spurious readings.
Dr. Matthew Oughton, an attending physician at Jewish General Hospital in Montreal who is not involved in the vaccine research, said earlier on Thursday that additional clinical trials could help provide better answers to questions as they come up about how effective and safe the vaccine is.