LONDON—The first study to directly compare immune reactions between Pfizer’s and AstraZeneca’s COVID-19 vaccines found strong and broadly similar antibody responses in over-80-year-olds after a first dose of either shot, scientists said on April 14.
The UK study also found that a critical component of the immune system known as T cells showed a more enhanced response in those who got the AstraZeneca/Oxford University vaccine than in those who got the Pfizer/BioNTech one.
