Spanish Study: Pfizer Dose After AstraZeneca Shot Safe and Effective

A first shot with the AstraZeneca vaccine followed by a dose of the Pfizer vaccine provides good protection against the coronavirus.

This is the conclusion of Spanish researchers after their own study with 600 test subjects.

Subjects who had already been vaccinated with AstraZeneca and subsequently received a Pfizer shot had a 30- to 40-fold more excellent immune response than those who received a dose of AstraZeneca alone.

In addition, few severe side effects were reported. According to the researchers, combining these two vaccines is therefore “safe and effective,” the researchers said.

The so-called Combivacs study was conducted by the Carlos III Health Institute in Madrid.