Britain has launched a trial to assess the immune responses generated if doses of the Covid-19 vaccines from Pfizer-BioNtech and AstraZeneca are combined in a two-shot schedule.
The British researchers behind the trial said data on vaccinating people with the two different types of coronavirus vaccines could help understanding of whether shots can be rolled out with greater flexibility around the world.
Initial data on immune responses is expected to be generated around June. The trial will examine the immune responses of an initial dose of the Pfizer vaccine followed by a booster of AstraZeneca's, as well as vice versa, with intervals of four and 12 weeks.