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J&J Booster shots


A more recent controversy has come up with the Johnson & Johnson (J&J) vaccine perhaps needing a booster shot sooner than the mRNA based vaccines for COVID-19.   A current problem is there is no verifiable data or rather limited data to support this reasoning and especially giving a Pfizer or Moderna vaccine as the booster instead of another shot of the J&J.  According to an article by Castaneda on August 19, 2021 in Clinical Trials Arena, there is limited data to support J&J recipients of needing a 2nd dose and their single dose data has shown the vaccine to still be potent in the face of durability and the delta variant.

According to J&J themselves, they have been analyzing their own data amongst study participants and saw that booster shots increased the antibody responses for those who had one shot of their vaccine.  Their claim is that they look forward to discuss these results to decide about boosting after eight months or longer after a single dose vaccination. What they haven’t described though is how they got to those results and actually show these preliminary results.  We know nothing about how they are analyzing these results other than they studied this amongst their Phase ½ study participants.  How they selected patients at which to look raises concerns about potential selection bias.

J&J did not discuss boosting their vaccine with a 2nd dose being from Moderna or Pfizer.  Perhaps for obvious reasons they would be less interested in combining their product with their competitors.  In Europe, where AstraZeneca has been offered and has similarities to the J&J vaccine, there has been this combination of having Moderna or Pfizer as the booster.  The jury is still out about boosters of the J&J vaccine and if so, when this should happen and for whom this should happen.


COVID-19, vaccines, efficacy, J&J, data analyses, selection bias, Usha Govindarajulu



Castaneda, Reynald, (August 19, 2021) “Single-dose J&J Covid-19 vaccine: single or double boosters, or none at all?”

Jansen Pharmaceuticals, (August 25, 2021) “Johnson & Johnson Announces Data to Support Boosting its Single-Shot COVID-19 Vaccine”