The Doherty Institute has been funded to conduct a unique Phase I study of two second generation COVID-19 variant vaccines. 

The Doherty Institute, a joint venture between the University of Melbourne and the Royal Melbourne Hospital, received funding from the National Health and Medical Research Council (NHMRC) under the Medical Research Future Fund.

SARS-CoV-2, the virus that causes COVID-19, is enveloped by proteins that resemble spikes, which enable the virus to attach and enter cells in our bodies. This attachment is mediated by the tip of the spike protein, known as the receptor binding domain (RBD). Our vaccine candidates focus specifically on the RBD because if we can block this attachment we can block infection.

The vaccines in our trial use two very different approaches:

  1. RBD protein – represents the tip of the spike to focus the immune response on this critical region of the virus targeted by antibodies that neutralise viral infectivity.
  2. RBD mRNA – represents the virus genetic sequence that codes for the tip of the spike, which will lead to production of the RBD protein.

The protein vaccine candidate has been developed by scientists at the Doherty Institute, and the mRNA vaccine candidate by scientists from the Monash University Institute for Pharmaceutical Sciences.

This will be the first time a side-by-side comparison will be undertaken of two COVID vaccines.

If the study is approved by the usual Ethics Review process, healthy adult volunteers aged between 18 and 70 years will be invited to voluntarily participate. We will need to recruit those who have been double vaccinated, and have received their second COVID vaccine dose (either Pfizer or AstraZeneca) at least three months before their enrolment in the study. These volunteers will be randomised to receive one dose of a study vaccine (protein or mRNA) or placebo, and then followed up over six months.

We are planning to begin the study in Melbourne in either early December 2021 or possibly January 2022.

Some healthy adult COVID unvaccinated volunteers will also be required, and they will receive two doses of either the protein or mRNA vaccine one month apart.

If you live in Melbourne and are interested in learning more about this study, please register your interest at our website, Vax4COVID.

Once the study is approved by the Ethics Committee, we will be able to provide full details of the study and what is involved.

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