4 ms·

If the vector is replicating, does that explain some piece of why Sputnik V is significantly more effective than the other adenovirus vector vaccines? (If that'

If the vector is replicating, does that explain some piece of why Sputnik V is significantly more effective than the other adenovirus vector vaccines? (If that's even true, of course, since it may well not be!) Or is it simply a more effective preparation of a vaccine, due to things like the Ad5/Ad26 combination?

marcosdumay 6y ago
Has there been any controlled study on the efficacy of Sputnik V? I haven't heard of any.
- drewblaisdell 6y ago
  You're asking if there has been any controlled study of Sputnik V, a vaccine which has been administered to millions?
- sanxiyn 6y ago
  Yes there has been. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00234-8/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6...
dragonwriter 6y ago
> If the vector is replicating, does that explain some piece of why Sputnik V is significantly more effective than the other adenovirus vector vaccines? The observed discrepancy between the delivered vaccine and the one described in the published clinical trial could, if not explain, hint at the reason the published clinical results are better than other vaccines in the same class.
Exmoor 6y ago
Unlikely, because the part of the adenovirus they delete that allows it to replicate is what they replace with the portion that generates the spike protein antigen. So if some of the adenovirus is replicating it's inherently not doing what you want it to do to produce an immune response.
- petertodd 6y ago
  Not inherently. We don't know how it's replicating. Furthermore, this isn't even an an/or situation: the actual virus in the vial of vaccine isn't going to be 100% uniform. You could have both virus material that can and can't replicate simultaneously. The extra immune response induced by the subset that can replicate might even make the immune response against the spike protein stronger, even if your theory is correct. Remember that vaccines usually have to use adjuvants to induce a stronger immune response than the active part itself does. An actual infection could do that quite effectively.
cblconfederate 6y ago
More importantly is it possible to infect others with the vaccine?

marcosdumay 6y ago

Has there been any controlled study on the efficacy of Sputnik V? I haven't heard of any.

drewblaisdell 6y ago
You're asking if there has been any controlled study of Sputnik V, a vaccine which has been administered to millions?
sanxiyn 6y ago
Yes there has been. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00234-8/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

dragonwriter 6y ago

> If the vector is replicating, does that explain some piece of why Sputnik V is significantly more effective than the other adenovirus vector vaccines? The observed discrepancy between the delivered vaccine and the one described in the published clinical trial could, if not explain, hint at the reason the published clinical results are better than other vaccines in the same class.

Exmoor 6y ago

Unlikely, because the part of the adenovirus they delete that allows it to replicate is what they replace with the portion that generates the spike protein antigen. So if some of the adenovirus is replicating it's inherently not doing what you want it to do to produce an immune response.

petertodd 6y ago
Not inherently. We don't know how it's replicating. Furthermore, this isn't even an an/or situation: the actual virus in the vial of vaccine isn't going to be 100% uniform. You could have both virus material that can and can't replicate simultaneously. The extra immune response induced by the subset that can replicate might even make the immune response against the spike protein stronger, even if your theory is correct. Remember that vaccines usually have to use adjuvants to induce a stronger immune response than the active part itself does. An actual infection could do that quite effectively.

cblconfederate 6y ago

More importantly is it possible to infect others with the vaccine?