3 ms·

seems like there's some consensus on two "exposures" worth of immunity being valuable. any data on second shots for folks who took the J&J?

lol768 5y ago
I don't think they've published any data relating to ENSEMBLE 2 yet.
Scoundreller 5y ago
The cynical part of me thinks that J&J is only 1 shot because your body develops strong immunity to it adenovirus-26 vector, so a 2nd shot would get immediately killed off before its spike protein payload could take any action. Until your immunity to it wanes anyway.
- Throwawayaerlei 5y ago
  This is suspected to be a problem with the Oxford vaccine which also uses one virus vector for both doses. Like Sputnik V, J&J's Janssen unit's Ebola vaccine uses two different virus vectors. And Janssen is doing an ENSEMBLE 2 Phase III clinical trial with two doses eight weeks apart that lol768 mentions. But their primary objective stated from the very beginning was to create the most effective single dose vaccine possible, and vaccinated a billion people in 2021. They appear to have achieved the former, although Sputnik Lite with the same Ad26 based vector could be a competitor, the latter goal is failing due to inherent issues with using cell culturing to make something, a strained supply chain for that which is also required to make Oxford's Sputnik V, and Novavax's vaccine (bug cell grown protein plus adjuvant), and being forced to use the dangerously incompetent Emergent BioSolutions as a subcontractor.
  - Scoundreller 5y ago
    Was J&J the most effective vaccine after 1 dose? Sure they don't have much competition if you only compare against 'approved' schedules, but mRNA vaccines seem better after 1 dose than J&J is. But yeah, there's just not a lot of trial data out there for 1dose mRNA or Oxford vaccine since they're (officially) pretty quick to get you to 2 doses. Emergent BioSolutions was contamination between the J&J side of production with the Oxford/AstraZeneca vaccine side of production...

lol768 5y ago

I don't think they've published any data relating to ENSEMBLE 2 yet.

Scoundreller 5y ago

The cynical part of me thinks that J&J is only 1 shot because your body develops strong immunity to it adenovirus-26 vector, so a 2nd shot would get immediately killed off before its spike protein payload could take any action. Until your immunity to it wanes anyway.

Throwawayaerlei 5y ago
This is suspected to be a problem with the Oxford vaccine which also uses one virus vector for both doses. Like Sputnik V, J&J's Janssen unit's Ebola vaccine uses two different virus vectors. And Janssen is doing an ENSEMBLE 2 Phase III clinical trial with two doses eight weeks apart that lol768 mentions. But their primary objective stated from the very beginning was to create the most effective single dose vaccine possible, and vaccinated a billion people in 2021. They appear to have achieved the former, although Sputnik Lite with the same Ad26 based vector could be a competitor, the latter goal is failing due to inherent issues with using cell culturing to make something, a strained supply chain for that which is also required to make Oxford's Sputnik V, and Novavax's vaccine (bug cell grown protein plus adjuvant), and being forced to use the dangerously incompetent Emergent BioSolutions as a subcontractor.
- Scoundreller 5y ago
  Was J&J the most effective vaccine after 1 dose? Sure they don't have much competition if you only compare against 'approved' schedules, but mRNA vaccines seem better after 1 dose than J&J is. But yeah, there's just not a lot of trial data out there for 1dose mRNA or Oxford vaccine since they're (officially) pretty quick to get you to 2 doses. Emergent BioSolutions was contamination between the J&J side of production with the Oxford/AstraZeneca vaccine side of production...