Thanks to @JanetDaly5 for flagging this. First animal data from #chadox1 #SARSCoV2 vaccine. Not sterilising immunity, but reduced viral load and pathogenesis, with half dose, BUT very quick challenge 4 week. (recall questioning this previously):
biorxiv.org/content/10.110…
biorxiv.org/content/10.110…
1/n
worth considering these data in detail; and what they might or might not mean
worth considering these data in detail; and what they might or might not mean
2/n
Firstly, the challenge dose. This was a relatively large amount of virus, BUT for people exposed to virus for considerable periods of time and/or large amounts (household member or healthcare worker) then protection against higher viral load exposure is relevant.
Firstly, the challenge dose. This was a relatively large amount of virus, BUT for people exposed to virus for considerable periods of time and/or large amounts (household member or healthcare worker) then protection against higher viral load exposure is relevant.
3/n
Regarding the vaccine dose. Previous ChAd data shows that 10-fold increases in vaccine dose can improve immune response sugnificantly, but don't expect miracles from a two-fold increase.
Regarding the vaccine dose. Previous ChAd data shows that 10-fold increases in vaccine dose can improve immune response sugnificantly, but don't expect miracles from a two-fold increase.
4/n
The virus challenge time, or when the animals were exposed to virus. This was timed to coincide with the point when animals were very likely at their peak of immunity. Long enough after immunisation to allow immunity to build, but not too long after when immunity might wane.
The virus challenge time, or when the animals were exposed to virus. This was timed to coincide with the point when animals were very likely at their peak of immunity. Long enough after immunisation to allow immunity to build, but not too long after when immunity might wane.
5/n
The fact that virus could still be detected in the vaccinated animals might be significant. Shedding of virus, even though low viral load, could potentially allow vaccinees to have mild infection (maybe even no symptoms) BUT be able to pass that virus on to others...
The fact that virus could still be detected in the vaccinated animals might be significant. Shedding of virus, even though low viral load, could potentially allow vaccinees to have mild infection (maybe even no symptoms) BUT be able to pass that virus on to others...
6/n
The most vulnerable people are often those with weaker immunity (not fit healthy young monkeys) so it's very unclear how this vaccine (or indeed any vaccine) will work in those groups
The most vulnerable people are often those with weaker immunity (not fit healthy young monkeys) so it's very unclear how this vaccine (or indeed any vaccine) will work in those groups
7/7
And final observation. Whilst none of the vaccinated animals had pneumonia half showed signs of clinical illness. So, is your glass half empty or half full?
And final observation. Whilst none of the vaccinated animals had pneumonia half showed signs of clinical illness. So, is your glass half empty or half full?
