The latest results from the COV-BOOST trial, ran at the Oxford University Hospitals NHS Foundation Trust show that a fourth dose mRNA vaccine is safe and boosts antibody levels - higher than that of a third dose.
Researchers have published their findings today in The Lancet Infectious Diseases.
Fourth doses of COVID-19 vaccines have been offered as a spring booster for those most vulnerable in the UK. This has been a precautionary strategy to maintain high levels of immunity prior to the study data being available. A wider group of people may be offered a fourth dose booster later this year.
The latest findings show that fourth dose mRNA booster vaccines for COVID-19 are well-tolerated in people who received Pfizer as a third dose. They are also effective at increasing both antibody and cellular immunity up to and above baseline and peak levels observed following third dose boosters.