(AP) — AstraZeneca insists that its COVID-19 vaccine is strongly effective even after counting additional illnesses in its US study, the latest in an extraordinary public dispute with American officials.
In a late-night news release Wednesday, the drugmaker said it had analysed more data from that study and concluded the vaccine is 76 per cent effective in preventing symptomatic COVID-19, instead of the 79 per cent it had reported earlier in the week.
Just a day earlier, an independent panel that oversees the study had accused AstraZeneca of cherry-picking data to tout the protection offered by its vaccine. The panel, in a harsh letter to the company and to US health leaders, said the company had left out some COVID-19 cases that occurred in the study, a move that could erode trust in the science.
Some experts said the new data provided by AstraZeneca was “reassuring” and that the information was likely solid enough for US regulators to authorise the vaccine.
“AstraZeneca may have just been too hasty in submitting the earlier, incomplete interim analysis rather than waiting to analyse and submit the full dataset,” said Julian Tang, a virologist at the University of Leicester who was not connected to the research. He said the updated details didn’t look substantially different from what was published earlier this week.
Data disputes during ongoing studies typically remain confidential but in an unusual step, the National Institutes of Health publicly called on AstraZeneca to fix the discrepancy.
AstraZeneca had been counting on findings from a predominantly US study of 32,000 people to help rebuild confidence in a vaccine that, despite being widely used in Britain, Europe and other countries, has had a troubled rollout. Previous studies have turned up inconsistent data about its effectiveness, and then last week a scare over blood clots had some countries temporarily pausing inoculations.
Most have since restarted after the European Medicines Agency said the vaccine doesn’t increase the overall incidence of blood clots, though it did not rule out a connection to some rare clots.