COVID-19 Fourth Dose Study

The Murdoch Children's Research Institute is seeking adult participants to help understand what vaccine schedules provide the best immune responses and safety profile, and how often people need to be boosted.

Study Description/ Purpose

Have you had your fourth dose? If not, consider joining the COVID-19 Fourth Dose study! Help researchers understand which vaccine strategies provide the best safety and protection to fight against COVID-19. This study is led by the Murdoch Children’s Research Institute in partnership with the Coalition for Epidemic Preparedness Innovations.

What’s Involved?

You can choose to get a 4th dose (randomised to receive Moderna or Novavax), or choose to be in a control group with no 4th dose.

Participants will be asked to provide up to 4 blood samples and 3 follow-up phone calls over 12 months.

Experienced phlebotomists or nurses will take blood at the Royal Children’s Hospital, Melbourne.

Recruitment criteria

You can participate if you are aged 18 years or older, have received three doses of any COVID-19 vaccine and have not yet received a fourth dose.

This study is being conducted in Melbourne.


At each in-person visit, participants will receive a $20 gift voucher and parking/public transport reimbursement.

Study sponsor / funder

Research team contacts

COVID Booster Study Team

Register your interest

    Please sign up on Join Us here
    You need to be registerd to deterime if you quilify for the study