A first-in-human clinical trial in healthy young and elderly adults to assess the safety, immunogenicity and exploratory evaluation of efficacy of a self-amplifying ribonucleic acid (saRNA) vaccine encoding the S glycoprotein of SARS-CoV-2, the causative agent of COVID-19.


Status: Open, with recruitment

CPMS ID: 46068

IRAS ID: 279315

Research summary
COVAC1 is a study that is looking at the use of a new vaccine against the virus (SARS-CoV-2) which causes COVID-19. There are two parts to the study. One part is to assess the safety of this vaccine, since this will be the first time that it has been used in humans. The second part is to see how well, and for how long, the vaccine activates the immune system. It is this activation that may provide protection against developing COVID-19. But this trial is NOT looking at whether or not the vaccine is effective in terms of protection. It is just assessing whether and how well the immune system responds.

Since this is the first time the vaccine has been used in humans, the safety will be assessed initially in healthy young adults. 15 participants aged 18-45 will be given one of three different doses (0.1, 0.3 and 1 µg) by injection into the muscle, going slowly from the lowest to the highest over a period of several weeks. There will be careful monitoring for any reactions to the vaccine.

As long as there are no safety concerns, the second part of the study can then be started. This will see how well the immune system has been activated using different dose levels of the vaccine. About 100 participants aged 18-45 will be given one of three doses (0.1, 0.3 and 1 µg). Chance will determine which dose each individual is given. The vaccine is given by injection into the muscle of the upper arm. Two injections, four weeks apart, are needed. There are likely to be mild side-effects near to the injection site. There may also be more general side-effects such as headache, temperature and chills. Participants will be asked to record any symptoms in an online diary. In order to see how well the immune system is responding, participants will need to give blood samples several times during the first 6 weeks; then monthly for a few months; then at 6 months and 12 months. This will happen at one study centre.

In addition, as long as there are no serious adverse events after about 6 weeks of the second part of the trial, the safety evaluation will be expanded. A further 200 people or more, from multiple sites, will be recruited. The safety of the highest vaccine dose (1 µg) will be assessed. The age range will now also be extended to include people up to the age of 75. This is important, since we know older people are more at risk of serious complications from COVID-19, and so are most likely to benefit from a successful vaccine.

An independent steering committee will regularly review the information on safety and look at the immune responses to see which dose of the candidate vaccine should go forward to effectiveness testing in future trials. Before this study can start, the protocol describing the procedures and information to be provided to volunteers will be reviewed by the national drug authority and a multi-centre research ethics committee.