Pharmaceutical AstraZeneca and the British University of Oxford will resume testing its coronavirus vaccine to be more certain about its efficacy, after initial results raised doubts due to a scientific error.
In the partial findings, announced Monday, it was indicated that the vaccine had an average 70% effectiveness against COVID-19: it was a mean between just over 60% protection for those who received two full doses and 90% for patients who received
a half dose first and a full dose in the second inoculation.
These differences have surprised and confused experts because it is rare that there is a better immune response when less product is given.
In addition, the University of Oxford said Wednesday that the half dose was initially not given on purpose: it was the result of a manufacturing problem that over-diluted certain ampules.
Afterwards, the protocol was changed to do the test taking into account the lower concentration.
But fewer patients received the half dose, a
small
group
of people, especially young people, who may not be representative
of how the entire population that uses the vaccine will respond.
"Now that we found that it would be more effective [to give half a dose first], we need to evaluate it and
that requires an additional study
," the director of the pharmaceutical company, Pascal Soriot, told the Bloomberg news service on Thursday.
The AstraZeneca and Oxford vaccine is of special global interest because it is the
cheapest alternative of those that are being developed
, so if it receives regulatory approval it is the option that more countries could afford to protect their population.
"This was a very lucky mistake," Nicola Stonehouse, a professor of molecular virology at the University of Leeds, told NBC News.
"It's an experiment and sometimes the experiments don't go as you expect," he added, "sometimes things are unexpected.
But they found out what happened, and that's called good experimental science. "
But Stonehouse cautioned that
only a summary of the results has been released
so far
, not the full data
, and that rigorous scrutiny by regulators will be necessary to ensure the results do not undermine public confidence in the global effort to vaccinate. to billions of people.
With information from NBC News.