LONDON (Reuters) – Britain on Thursday launched a trial to assess the immune responses generated if doses of Pfizer Inc and AstraZeneca Plc’s COVID-19 vaccines are combined in a two-shot plan.
British researchers behind the trial said data on vaccination of people with two different types of coronavirus vaccines could help understand whether shots can be fired with greater flexibility around the world. Initial data on immune responses are expected to be generated by June.
The trial will examine the immune responses of an initial dose of Pfizer vaccine followed by an AstraZeneca booster, as well as vice versa, at 4- and 12-week intervals.
Both the mRNA vaccine developed by Pfizer and Biontech and the adenovirus viral vector vaccine developed by Oxford University and AstraZeneca are currently being rolled out in the UK, with a 12-week difference between two doses of the same vaccine. .
More vaccines are expected to be added to the trial when they are approved and launched.
The researchers noted that recruitment for the study begins Thursday and more than 800 participants are expected to participate. This makes it much smaller than the clinical trials that have been used to determine the effectiveness of vaccines individually.
The trial will not evaluate the overall effectiveness of the shot combinations, but the researchers will measure antibody and T cell responses, as well as monitor for unexpected side effects.
Matthew Snape, an Oxford vaccinologist leading the trial, said initial results could report the deployment of the vaccine during the second half of the year.
“We will get some results, hopefully, by June or wherever the use of booster doses is reported in the general population,” he told reporters.
The trial seeks to recruit people over the age of 50 who may be at higher risk than younger people and who have not already been vaccinated.
The AstraZeneca trait is also being tested in combination with Russia’s Sputnik V vaccine, and the British pharmacist’s head of research has said more studies should be done on the combination of vaccines.
Alistair Smout Reports; Edited by Bill Berkrot