Com-COV was a trial that Dr. Snape and colleagues started in February. They gave 830 volunteers four vaccine combinations in the initial wave. Two doses of Pfizer BioNTech or AstraZeneca were given to some of the participants. Both of these vaccines have been proven effective against Covid-19. Some received AstraZeneca, followed by one dose of Pfizer or vice versa.Two doses of Pfizer BioNTech resulted in antibodies that were about 10 times higher than those who received two doses AstraZeneca. The antibody levels of volunteers who were given Pfizer BioNTech and AstraZeneca followed by Pfizer-BioNTech were five times higher than those who had received two doses.Volunteers who received AstraZeneca and Pfizer BioNTech had antibodies that were about the same as those who received two doses.Researchers also found promising results when they examined levels of immune cells that were primed to attack coronavirus. The cells produced by mixing the vaccines were higher than two doses of one vaccine.Snape stated that it was not yet clear why mixing conferred that advantage. It is very interesting, let's say so.Dr. Snape has started another similar trial with his colleagues, which includes vaccines from Novavax and Moderna. He did not recommend a routine mix and match strategy. He said that for now, two doses of the vaccine are the best.This strategy has been proven effective in reducing the chance of getting Covid-19 through large clinical trials. Dr. Snape stated that your default should be the one that has been proven to work.
