You'll hear buzz about the new single-dose "viral vector" COVID-19 vaccine from Johnson & Johnson/Janssen (Ad26.COV2.S).
Similarly to the Pfizer-BioNTech or Moderna mRNA COVID-19 vaccines, viral vector vaccines give our cells instructions to make the SARS-CoV-2 spike protein...to trigger an immune response.
But they do it in different ways. The mRNA COVID-19 vaccines give our cells an mRNA blueprint. Johnson & Johnson's COVID-19 vaccine delivers instructions using an adenovirus "vector" that's modified and harmless.
Educate that both platforms have been studied for years...these are not live vaccines...and overall adverse effects are similar.
Point out that the Johnson & Johnson product is just one IM dose for now...plus it can be stored in a fridge for months.
Answer questions about efficacy. Patients are hearing that the Pfizer-BioNTech or Moderna 2-dose vaccine has roughly 95% efficacy against COVID-19...and Johnson & Johnson's 1-dose vaccine has about 70% efficacy.
But explain that these comparisons aren't "apples to apples"...partly because the trials vary in where and when they took place.
For example, Johnson & Johnson's vaccine may have faced a tougher test...due to viral variants that weren't circulating widely during mRNA COVID-19 vaccine clinical trials.
Johnson & Johnson's vaccine still seems to have about 60% efficacy overall in South Africa...where nearly all cases are from a variant.
Early mRNA COVID-19 vaccine lab studies suggest reduced antibody response to some variants. But this is just one measure of protection...the vaccines may maintain much of their real-world efficacy.
Emphasize the big picture. Each of these three vaccines seems to have at least 85% efficacy at preventing SEVERE COVID-19...such as cases leading to ICU admission or death.
Plus their efficacy is well over the 50% threshold that FDA requires to authorize COVID-19 vaccines.
Highlight other benefits. Immunization will be key in moving toward herd immunity. Plus it should help to slow mutations, since replication opens the door for the virus to mutate.
Use our chart, COVID-19 Vaccines, to keep details straight...and for background on other upcoming vaccines.
- N Engl J Med Published online Jan 13, 2021; doi:10.1056/NEJMoa2034201
- www.fda.gov/media/146217/download (2-24-21)
- JAMA 2021;325(6):529-31
- www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html (2-24-21)
- www.cdc.gov/vaccines/covid-19/hcp/viral-vector-vaccine-basics.html (2-24-21)
- Chart: COVID-19 Vaccines