Study shows AZ is safe and effective when mixed with Pfizer vaccine

A preliminary study published in Spain on the 18th revealed that a COVID-19 vaccine mix study found that administering another dose of Pfizer vaccine to people who had received the first dose of AZ (Astroglide) vaccine was not only highly safe but also effective.

Central News Agency (CNA) reported that the Carlos III Health Institute, a Spanish government-supported institute, conducted a study of a combination vaccine (Combivacs) for coronavirus disease 2019 (COVID-19).

Approximately 670 volunteers aged 18 to 59 years who participated in this study had received their first dose of the AstraZeneca vaccine (referred to as the AZ vaccine).

The subjects were divided into two groups, with about 450 receiving an additional dose of the Pfizer vaccine and the remaining 220 in a control group that did not receive another vaccine.

The study found that compared to the control group who received only one dose of AZ vaccine, those who received an additional dose of Pfizer vaccine had 30 to 40 times higher levels of IgG antibodies in their bloodstream.

At the same time, subjects who received an additional dose of Pfizer vaccine had a seven-fold increase in the amount of neutralizing antibodies in their bodies, much higher than the dual effect observed after a second dose of AZ vaccine.

Dr. Magdalena Campins, one of the study leaders, noted that only 1.7% of the subjects reported serious side effects, which were limited to headaches, muscle pain and general discomfort.

Another AFP report: The latest study by U.S. scientists shows that two COVID-19 vaccines, Pfizer & BNT and Moderna, are still highly effective against the two mutated viruses that first appeared in India.

However, such laboratory studies are not predictive of effectiveness in real-world situations and must be validated through additional studies.

The laboratory study, conducted by the NYU Grossman School of Medicine and NYU Langone Medical Center, has not yet been published in a peer-reviewed journal and is therefore considered preliminary.

Nathaniel “Ned” Landau, senior author of the study, told AFP: “We found that the vaccine antibodies were slightly weaker in the face of the mutated virus, but not that much weaker, so we think the vaccine is still very protective.