Both Moderna and Pfizer have recently submitted data to US authorities to defend a third dose.
The American pharmaceutical company Moderna defended the use of booster doses of its COVID
on Wednesday, based on new data on the apparent decrease in its effectiveness over time.
The company released details of a study in which it compares the cases of coronavirus
registered between participants in its clinical trials, who were vaccinated between July and October 2020, and people who were vaccinated between December 2020 and March this year, when the product had already received authorization for emergency use.
According to Moderna, the number of COVID
-19 cases is clearly higher in the first group, which would point to a progressive decrease in the immunity provided by the vaccine
In a statement, the CEO of the firm, Stéphane Bancel, said that these conclusions "support the need for reinforcements to maintain high levels of protection."
"We hope these findings will be helpful as health authorities and regulators continue to analyze strategies to end this pandemic," Bancel said.
Both Moderna and Pfizer
, the two companies with messenger RNA vaccines
, have recently submitted data to US authorities to defend a third dose.
So far, booster doses are being used for people with a weakened immune system, while there is no decision on their use in the general population.
In the note published today, Moderna also contributed new studies on the efficacy of its vaccine
, which suggest that it continues to work well, also against the delta variant.
The analysis compared more than 350,000 people vaccinated with this product with a similar number of those who were not vaccinated and showed an effectiveness of 87% in the diagnosis of COVID
-19 and 96% in preventing hospitalization.
The study, which has not yet been reviewed by independent bodies, was carried out with a significant presence of the delta variant, which was detected in 47% of the cases registered among those vaccinated, according to Moderna.