Astrazeneca insists vaccine highly effective
Astrazeneca found its COVID-19 vaccine to be 76 percent effective even after counting additional illnesses in its U.S. study, the latest in an extraordinary public dispute with American officials.
On Tuesday, an independent panel that oversees the study had accused Astrazeneca of cherrypicking data in concluding that its vaccine was 79 percent effective. The panel, in a harsh letter to the company and to U.S. 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.
But in a late-night news release Wednesday, the drugmaker said it had analyzed more data from that study and found the vaccine’s efficacy to be just 3 percentage points lower than the earlier estimate.
Astrazeneca’s newest calculations were based on 190 COVID-19 cases that occurred during the study, 49 more than it had included earlier in the week.
The vaccine appears especially protective against the worst outcomes, with no severe illnesses or hospitalizations among vaccinated study volunteers compared with eight severe cases among those given placebos, the company said
Some experts said the new data provided by Astrazeneca was “reassuring”
and that the information likely was solid enough for U.S. regulators to authorize the vaccine.
“Astrazeneca may have just been too hasty in submitting the earlier, incomplete interim analysis rather than waiting to analyze and submit the full dataset,” said Julian Tang, a virologist at the University of Leicester who wasn’t 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 are confidential, but in an unusual step, the National Institutes of Health publicly called out Astrazeneca.
Astrazeneca had been counting on findings from a predominantly U.S. 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 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 didn’t rule out a connection to some rare clots.
On Thursday, Denmark announced it would continue its suspension of the vaccine, with officials saying they needed more information before making a decision.
The question now is whether the company’s newest calculations can end the tension in the United States.
Even before the latest spat, experts had expressed concern that missteps in the vaccine’s rollout could undermine confidence in the shot, which is crucial to global efforts to end the coronavirus pandemic since it’s cheap, easy to store and a pillar of the COVAX initiative aimed at bringing vaccines to lowand middle-income countries.
Dr. Anthony Fauci, the top U.S. infectious disease expert, predicted Wednesday that it would “turn out to be a good vaccine.”