A FOURTH Covid-19 vaccine offers stronger immunity protection, a recent study has found.

The latest results from the Cov-boost trial, which ran at University Hospitals Sussex NHS Foundation Trust, show that a fourth dose is “safe and boosts antibody levels - higher than that of a third dose”.

A fourth dose of the vaccine has been offered as a spring booster to the most vulnerable people in the UK as a precautionary strategy.

A wider group of people will be offered a fourth dose booster later this year.

The latest findings show a fourth dose is 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.

Professor Saul Faust, trial lead, said: “These results underline the benefits of the most vulnerable people receiving current spring boosters and gives confidence for any prospective autumn booster programme in the UK, if the Joint Committee on Vaccination and Immunisation considers it needed at that time.”

In the fourth dose study across 10 UK sites, 166 people who had received a third dose of Pfizer following Pfizer or AstraZeneca initial doses in June 2021 were randomised to receive full dose Pfizer or half dose Moderna as a fourth dose. These were approximately seven months after their third dose.

Sunil Sharma, a consultant in infectious diseases and microbiology at University Hospitals Sussex NHS Foundation Trust, said: “We are delighted to have been involved in this important study. It is a real credit to our research team and the outstanding work that they do.

“I want to thank the 42 volunteers who took part at the Royal Sussex County Hospital. Their participation in this study will have helped provide the public with the confidence that fourth dose boosters are both safe and effective.”

While pain at the vaccination site and fatigue were the most common side effects, there were no vaccine-related serious adverse events, and fourth doses were safe and well-tolerated.

Professor Andrew Ustianowski, NIHR clinical lead for the Covid-19 vaccination programme and joint national infection specialty lead, said: “The study's latest results once again show the importance of sustained research into Covid-19 vaccines and how they are best used to keep the virus at bay.

“We knew that it was important to offer a fourth dose to those most vulnerable earlier in the year. These new study findings support that decision and provides the public with the confidence that fourth doses are both safe and even more effective than third doses at boosting immunity against COVID-19.

"It is thanks to the endless efforts and contribution of study participants and staff across the UK that we can keep discovering more about the use of vaccines, and they continue to play a pivotal role just as they have done throughout the pandemic."