AstraZeneca and Pfizer Covid-19 vaccines to be combined in Oxford trial

The University of Oxford is set to begin a trial combining Covid-19 vaccines from AstraZeneca and Pfizer that could enable greater flexibility in the use of scarce supplies globally.
 
The university will begin recruiting 820 participants over 50 years of age across eight UK sites this week, according to a statement Thursday.
 
The Astra and Pfizer vaccines will be given in different orders and with two dosing intervals, four and 12 weeks apart.
 

The trial will allow researchers to see whether two shots of different vaccines produce better or worse results than two doses of the same product. The study could be key to relieving pressure on individual vaccine makers to deliver shots if they run into manufacturing difficulties.

 
Mixing vaccines to create an enhanced immune response is common for inoculations targeting diseases such as hepatitis A and B.
 
Combining shots can boost the immune response because the second shot won’t be limited by any immunity the body has built up to the platform delivering the first vaccine.