Hello and welcome back to the Corner. In previous issues, we discussed COVID-19 vaccine products both in development and those that had been approved for emergency use by the FDA. With the most recent authorization given to Johnson & Johnson’s (J&J) product, I felt another update was warranted.
As we are all aware at this point, the FDA granted emergency use authorization (EUA) to both Pfizer-BioNTech and Moderna vaccine products for those age 16 and older back in December 2020. These vaccines require a two-shot series with a period of 21 to 28 days between administration. Data from clinical trials when these products were authorized suggested effectiveness of around 95% against COVID-19. As you may also recall, these vaccines use what is referred to as mRNA technology. This provides cells a blueprint to make a piece of the SARS-CoV-2 “spike” protein, which triggers the immune response.
The J&J vaccine is different from both the Pfizer-BioNTech and Moderna vaccines in a few ways. First, the J&J vaccine can be stored at refrigerated — as opposed to freezer — temperature conditions and requires only a single dose. This new vaccine uses what is referred to as “viral vector” technology. Whereas the other vaccines use mRNA technology to deliver the blueprint to our cells, this new product uses a modified and harmless viral vector to deliver the instructions. Both technologies result in our bodies mounting an immune response, protecting against COVID-19. As mentioned in previous issues, both mRNA and viral vector technology have been studied for years even though these are some of the first vaccines to truly use the technology.
Another thing worth mentioning is the relative effectiveness of the J&J product compared to the vaccines that have been in circulation for the past few months. It has been estimated that both the Pfizer-BioNTech and Moderna vaccines have efficacy rates around 95%, while the J&J single vaccine regimen is around 70%. One key thing to remember is that the trials for the J&J vaccine may have included variant COVID-19 viral strains that were not present during the Pfizer-BioNTech and Moderna trials. When a virus mutates to a different strain, there could be reduced effectiveness for any vaccine. This has been the case with the “South African” viral strain that has surfaced. The good news is that even including that strain, all vaccine products still exceed the 50% efficacy threshold that was set forth by the FDA for a vaccine product to be considered for use. Also, as with other vaccines, even with reduced effectiveness, the overall incidence of severe complications from infection is reduced in those that have been vaccinated.
The closer we get to that point, the closer we may get to getting back to life as we knew it before the pandemic.
Thanks again for stopping by and continue to stay safe and healthy.