A new COVID-19 vaccine based on a different mechanism of action than the current vaccines on the market has been tested in humans for the first time by researchers at Radboudumc. Administration of this vaccine in healthy volunteers was well tolerated and resulted in a good immune response. The effectiveness of the vaccine is currently being further investigated. First results are expected later this year.
The new vaccine, called ABNCoV2, is a different type than the vaccines against the coronavirus that have been marketed so far: the mRNA vaccines (such as those from Pfizer and Moderna), the vector vaccines (such as those from Janssen and AstraZeneca) and the protein vaccine Novavax. In this case it concerns a virus-like particle (VLP) vaccine. This means that the new corona vaccine consists of elements that resemble virus particles. To the immune system, these particles look like a virus, but they cannot multiply. The virus-like particles are connected to a small part of the coronavirus SARS-CoV-2. As a result, the body quickly responds to the virus by making antibodies and T cells.
Few side effects
This study, conducted by research physician Merel Smit, looked at the safety and tolerance of the vaccine. 45 healthy volunteers, who had not yet had COVID-19 and were not vaccinated, received two doses of the new vaccine. They were followed for six months after the second vaccination. The participants produced antibodies and T cells against SARS-CoV-2. In addition, the study showed that the vaccine was well tolerated by the study participants: few side effects were reported. Lead researcher Benjamin Mordmüller, professor of Medical Microbiology at Radboud university medical center: ‘This technology has exceeded our expectations in terms of immunity and tolerability.’ The results have now been published in The Lancet Microbe.
Further research is needed to establish the effectiveness of this vaccine. Several studies are currently underway into its effectiveness. Mordmüller is hopeful about this: a vaccine based on a similar principle is the vaccine against the HPV virus, which can cause cervical cancer, among other things. With this vaccine, immunity is guaranteed for a longer period of time; for more than ten years now. If this also applies to the new corona vaccine, this could mean that any booster vaccinations can be given at longer intervals.
Other infectious diseases
An important advantage of this type of vaccine is the ability to adapt it quickly in case the virus develops mutations that reduce the effectiveness of the ABNCoV2 vaccine. In addition, this so-called cVLP platform, the basis of the vaccine, can also be used for the further development of new improved vaccines for worldwide infectious diseases, such as malaria and influenza. That was not yet possible with the vaccine against the HPV virus. A malaria vaccine based on this vaccine is currently being developed and is expected to be tested next year.
Mordmüller: ‘The results are very good news for the development of vaccines against a wide range of infectious diseases for which conventional vaccines cannot provide adequate protection, if at all.’
About the publication
This study is published in The Lancet Microbe: First-in-human use of a modular capsid virus-like vaccine platform: an open-label, non-randomised, phase 1 clinical trial of the SARS-CoV-2 vaccine ABNCoV2 . Merel J Smit, Adam F Sander, Maud BPA Ariaans, Cyrielle Fougeroux, Constanze Heinzel, Rolf Fendel, Meral Esen, Peter G Kremsner, Rob ter Heine, Heiman F Wertheim, […] Willem A de Jongh, Matthew BB McCall, Morten A Nielsen, Benjamin G Mordmüller, on behalf of the COUGH-1 trial study group.
This vaccine was developed by the Danish biotechnology company AdaptVac, in collaboration with Radboudumc and the Prevent-nCoV consortium. Radboudumc was responsible for the design and implementation of the study.