Overview of the Moderna COVID-19 vaccine

The Moderna COVID-19 vaccine was one of the first vaccines to receive a conditional marketing authorisation for the EU at the beginning of January 2021. Find more information on the vaccine, its efficacy and possible adverse reactions here.

This is how the vaccine works

Vaccines such as Moderna’s contain gene segments of the SARS-CoV-2 virus in the form of messenger RNA (messenger ribonucleic acid or mRNA for short). Messenger RNA contains what could be referred to as the blueprint for a specific characteristic of the coronavirus – the so-called spike protein. The vaccine uses the smallest of fat particles (mRNA lipid nanoparticles) to introduce this blueprint into the cells. Studies have shown that these particles do not damage the cells, nor do they or pose any danger to the human
body.

After vaccination, the body’s cells manufacture proteins based on this “blueprint” (of the mRNA) that encourage the immune system to produce targeted antibodies to combat SARS-CoV-2 and mount a cellular defence against SARS-CoV-2 infected cells, thereby eliciting an immune response. These proteins are called antigens. Good to know: the messenger RNA is broken down by the body in a short period of time. It is not converted into human DNA and has no influence on the human genome. No further manufacture of antigens takes place after the mRNA has been broken down.

mRNA-based vaccines have the added advantage that a large number of vaccine doses can be manufactured within a few weeks. Furthermore, due to the building-block nature of mRNA vaccines, vaccine manufacturers can react quickly to mutations and adapt the vaccines to suit.

Study confirms high efficacy

The Moderna® COVID-19 vaccine is highly efficacious and prevents COVID-19 infection among the majority of those vaccinated. During the marketing authorisation study, the Moderna® COVID-19 vaccine achieved an average efficacy of around 95 percent. According to the results, the vaccine protects the younger age groups (18 to 65 years old) at a rate of 96 percent – even slightly better than persons over 65 years (86 percent). The vaccine was even able to significantly reduce the risk of severe disease progression (for example, hospitalisation as a result of respiratory failure). Further analysis of the clinical data points to a similar efficacy among participants with specific pre-existing conditions and risks (co-morbidities/attendant morbidities) such as obesity, chronic lung disease or diabetes.

To what extent boosters are necessary, as is the case with the influenza vaccine for example, is still unclear and will continue to be the subject of clinical trials.

Efficacy far exceeds the minimum requirements

The World Health Organization (WHO) required an efficacy of at least 50 percent for the licensing of coronavirus vaccines worldwide. With its efficacy of around 95 percent, the
Moderna® COVID-19 vaccine far surpasses that requirement.

Vaccine reactions and adverse reactions

In principle, as with all vaccines, coronavirus vaccines can lead to vaccine reactions and additional adverse reactions, irrespective of the pathogen or the vaccine. Even in the case of the Moderna® COVID-19 vaccine, so-called vaccine reactions can occur after vaccination; however, these disappear after a short period of time. Reactions may consist of pain at the injection site, headaches, muscle and joint pain, fatigue or flu-like symptoms.
These vaccine reactions are known from clinical trials and are usually no reason for concern. In consultation with your physician, you may take pain or fever-reducing medication in the recommended dosage to mitigate possible complaints.

In the information sheet on mRNA vaccines, you can find, among other things, precise information on the frequency of adverse events surrounding the Moderna® COVID-19 vaccine. The information sheet can be downloaded it here.

Information on adverse events is contained in the current product information texts that you can read here.

The benefits outweigh the disadvantages

The occurrence of vaccine reactions and/or temporary adverse reactions is no reason to avoid taking the vaccine; on the contrary, vaccinated persons benefit from the expected protection. Because it is clear that: with regard to all of the currently available COVID-19 vaccines, the European Medicines Agency (EMA) has determined that the advantages of the Moderna® COVID-19 vaccine outweigh the risk of possible, in some cases rare, adverse
events and vaccination complications.

Safety continuously monitored

If you have known intolerances or allergies to ingredients contained in the Moderna® COVID-19 vaccine or have had a severe allergic reaction to the first vaccination, you should avoid taking a second dose. You can find the package leaflets of all of the vaccines authorised against COVID-19, with the corresponding product information here. The safety of the COVID-19 vaccines is being monitored continuously. Indications of hitherto unknown, very rare possible adverse reactions are continuously examined and assessed to enable an immediate response if necessary.

You can read the corresponding safety reports from the Paul Ehrlich Institute here.