Pfizer Booster Increases Antibodies 175-fold, Says Health Study

A study by the Ministry of Health carried out in partnership with the University of Oxford shows that the booster dose of Pfizer’s vaccine increased the number of neutralizing antibodies by 175 times.

The number is almost three times greater than that of other immunization agents applied in Brazil. With the Astrazeneca vaccine the increase was 85 times and with the Janssen vaccine it was 61 times.

The immunizing agent Coronavac had the lowest immune response, with a seven-fold increase in neutralizing antibodies.

The data were presented at a press conference at the Ministry of Health this Friday (17).

All booster doses were given six months after the application of the two doses of Coronavac. The study was carried out with 1205 volunteers in São Paulo and Salvador.

Oxford University researcher and professor Sue Ann Costa Clemens explained that the higher the level of neutralizing antibody, the greater the protection.

“About 80% of the individuals in the study did not have detectable neutralizing antibodies to the strains circulating in Brazil: delta and gamma. A booster dose was then applied and, after 28 days, we verified that all vaccines stimulate the immune response”, he said.

So they concluded that the four vaccines worked to boost people’s immunity when given as a booster dose — but different vaccines showed greater effectiveness for people who had already taken Coronavac.

The study also points out that Pfizer, Astrazeneca and Janssen vaccines induced the formation of neutralizing antibodies in adults and the elderly. The Coronavac vaccine induced neutralizing antibodies in adults and only two-thirds of the elderly.