COVID-19 Vaccine Effectiveness: Pfizer·Moderna > Janssen·Novavax [Reading Science]

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[Asia Economy Reporter Kim Bong-su] According to the international academic journal Nature on the 30th, objective performance evaluation results of COVID-19 vaccines widely distributed worldwide, produced by Western bio companies, confirmed that mRNA vaccines such as Pfizer and Moderna outperform traditional vaccines like Janssen and Novavax.

Accordingly, the La Jolla Institute for Immunology in California, USA, published a paper with these findings on the preprint server bioRxiv on the 21st.

The research team tested four types of vaccines: Moderna, Pfizer, Janssen, and Novavax. Among these, the Moderna and Pfizer vaccines were produced using the mRNA method, which injects proteins designed to produce specific antibodies. The Janssen vaccine uses a 'viral vector' method, which involves injecting a dead influenza virus containing the spike protein of the COVID-19 virus into the human body to induce immunity. The Novavax vaccine was made using a gene recombination method known to have fewer side effects.

The research team evaluated these vaccines based on 14 criteria, including the levels of T and B cells and neutralizing antibodies generated upon vaccination. Notably, while previous studies drew conclusions by collecting data from various papers conducted with slightly different methods, this study analyzed all vaccines under the same conditions and techniques to increase accuracy. The team administered the Moderna, Pfizer, and Janssen vaccines to 30 individuals each, and the Novavax vaccine to 12 individuals, then collected blood samples to monitor changes in antibody and immune cell levels over time.

The results revealed relatively distinct differences in the effectiveness of the four vaccines. When Pfizer and Moderna vaccines were administered twice, the amount of antibodies produced was greater (based on a 6-month follow-up) than that after a single dose of the Janssen vaccine. However, the durability was better with the Janssen vaccine. While the antibody levels of Pfizer and Moderna vaccines significantly decreased after six months, those of the single-dose Janssen vaccine remained stable or even increased.

For the Novavax vaccine, the amount of antibodies generated after the second dose was similar to that of Pfizer and Moderna vaccines. However, the amount of T cells, which destroy virus-infected cells, showed almost no change and was barely detectable. In contrast, Moderna, Pfizer, and Janssen vaccines effectively activated T cell production.

Nature commented, "These results align with conclusions from previous studies," but also noted, "This study provides a more extensive and consistent analysis of vaccine effects on the immune system under the same conditions." Researcher Alessandro Sette stated, "This study does not determine winners or losers among COVID-19 vaccines," adding, "It offers a comprehensive evaluation of various variables."