Evaluating COVID-19 Vaccine Boosters

A randomised, phase II UK multi-centre study to determine reactogenicity and immunogenicity of booster vaccination against ancestral and novel variants of SARS-CoV-2

Closed to recruitment

Aims of the study

This study is trying to determine the side effect profile, safety, and immune response of giving a 3rd COVID-19 vaccine dose of BNT162b2 (Pfizer) to people who have previously received 2 doses of NVXCoV2373. We will be enrolling men and women 30 years old or over who received their initial prime-boost course of vaccination against COVID-19 with NVXCoV2373.

Eligibility criteria

  • Participant is willing and able to give written informed consent for participation in the trial.
  • Male or female aged 30 years or above
  • In the Investigator’s opinion, is able and willing to comply with all trial requirements.
  • Willing to allow their General Practitioner and consultant, if appropriate, to be notified of participation in the trial
  • Willing to allow investigators to discuss the volunteer’s medical history with their General Practitioner and access all medical records when relevant to study procedures.38 COV-Boost Protocol 15th December 2021 V8.0
  • Primary immunization course (2 doses) of NVXCoV2373 COVID-19 vaccine
  • Participant plans to receive 1 or 2 doses of licensed vaccine (1 dose will be received as part of this trial, the second dose will not be provided by the trial but the participant may receive a second dose via the NHS if they wish to)

What participating in the study involves

The COV-Boost study looks at the impact of different vaccines against COVID-19 when given as a booster vaccination. You are being invited to take part in a sub-study of the COV-Boost study where we are studying use of the BNT162b2 (Pfizer) COVID-19 vaccine when given as a 3rd dose booster after an initial COVID-19 vaccination course with the NVXCoV2373 (Novavax) vaccine. Participants that took part in the Novavax study now have the opportunity to access additional COVID-19 vaccinations through the NHS if they require proof of approved vaccines for international travel. This sub-study is to evaluate the safety and side effect profile of giving a dose of the Pfizer COVID-19 vaccine to these study participants, as well as assessing its impact on the immune response to the virus which causes COVID-19, called SARS-CoV-2.

Participants will all receive a single dose of the Pfizer COVID-19 vaccine. They will then complete a diary of their symptoms over the next 7 days, and any other adverse events which occur up to 3 months after having had the vaccine. There are several follow up visits to have blood tests to check for immune markers, and to check on the participants health.