AstraZeneca admits the best results in its COVID-19 vaccine study came from a dosing error, and experts are raising new questions about the shot – By Kate Duffy (Business Insider) / Nov 26 2020
- AstraZeneca and the University of Oxford are facing criticism over their COVID-19 vaccine trial results after admitting a mistake in the vaccine dosage.
- During the trial, some patients got two full doses of the vaccine, whilst others had a half-dose in their first shot, followed by a full dose.
- An AstraZeneca executive, Dr. Mene Pangalos, described the “mistake” as “serendipity”: The vaccine was 90% effective in the group with the initial half-dosage, compared to 62% effective in the full-dosage group.
- Some health experts have expressed concern about the mistake. “Astrazeneca/Oxford get a poor grade for transparency and rigor,” one biostatistician at the University of Florida said.
- Pangalos told the Wall Street Journal on Wednesday that the mistake was “irrelevant.”
AstraZeneca and the University of Oxford on Wednesday acknowledged a dosing error in their COVID-19 vaccine trial — and some health experts have said it has eroded their confidence in the shot.
The COVID-19 vaccine is on average 70% effective, according to the latest large-scale trial results announced Monday. The vaccine was found to be 62% effective in those who had two full doses, but rose to 90% effective in those who had a half-dosage in their first shot.
On Monday, AstraZeneca admitted that the half-dosage was initially a “mistake,” Reuters first reported. The plan was for patients in the British trial to receive two full doses of the vaccine one month apart, but some received a half-dose for their first shot instead.
“We went back and checked … and we found out that they had underpredicted the dose of the vaccine by half,” Dr. Mene Pangalos, an AstraZeneca executive responsible for the company’s research and development, told Reuters.
