4 ms·

This is a very early step (phase 1). They are giving the vaccine to small number of healthy people to make sure it is safe in that population. From there they h

This is a very early step (phase 1). They are giving the vaccine to small number of healthy people to make sure it is safe in that population. From there they have to go on to larger trials that look at both safety and effectiveness. The phase 2 and phase 3 trials will take much longer.

mattkrause 6y ago
Is this really a phase I? 800 people seems absolutely massive if it is—and I don’t think they’d bother with a placebo arm for safety. Edit: Found the registration. It’s a weird combined Phase I and II: https://clinicaltrials.gov/ct2/show/NCT04324606 https://clinicaltrials.gov/ct2/show/NCT04324606
- tialaramex 6y ago
  Well, it is complicated by the reality that this disease is widespread. I was rejected because I had cancer (years ago but they don't need any extra factors) but this is mostly like a normal Phase I in that the primary question is: Do humans tolerate this vaccine? Roughly half those recruited (at random) get a different vaccine, an irrelevant one, that protects against Meningitus but we've no reason to think would make any difference to a coronavirus - and half get the new one. You can't tell what it was they stuck in your arm, so they can compare the two groups to see if any side effects were significantly more common for the new vaccine. Because this coronavirus is widespread in the community they will also unavoidably get to collect information that would usually be the purpose of Phase II/III trials - did the group who got the "real" vaccine get COVID-19 symptoms less often that the other group? Or if they did, were they less severe? You normally don't do this, and if you tried an ethics committee would stop you - it's unethical to expose patients to a novel risk when you haven't even figured out if the treatment you're trying is safe first. But in this case the risk is already there, for absolutely everyone, so you aren't making anything worse by just measuring if your treatment helped.
  - mattkrause 6y ago
    Right, but for those same reasons, a Phase I trial is usually much smaller and has “safety and tolerability” as an endpoint rather than disease-related outcomes (as this one does). I don’t think those usually have randomized control groups; see the example below. In this case, it looks like the Oxford group had previously used the same ChAdOx platform to make a MERS vaccine, and they’re leveraging that data (here: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30160-2/fulltext# https://www.thelancet.com/journals/laninf/article/PIIS1473-3...) to move more quickly into a combined Phase I and II trial.
billfruit 6y ago
And I think there are also some 4 or five vaccines in phase 1. See report https://www.nature.com/articles/d41573-020-00073-5 https://www.nature.com/articles/d41573-020-00073-5

mattkrause 6y ago

Is this really a phase I? 800 people seems absolutely massive if it is—and I don’t think they’d bother with a placebo arm for safety. Edit: Found the registration. It’s a weird combined Phase I and II: https://clinicaltrials.gov/ct2/show/NCT04324606 https://clinicaltrials.gov/ct2/show/NCT04324606

tialaramex 6y ago
Well, it is complicated by the reality that this disease is widespread. I was rejected because I had cancer (years ago but they don't need any extra factors) but this is mostly like a normal Phase I in that the primary question is: Do humans tolerate this vaccine? Roughly half those recruited (at random) get a different vaccine, an irrelevant one, that protects against Meningitus but we've no reason to think would make any difference to a coronavirus - and half get the new one. You can't tell what it was they stuck in your arm, so they can compare the two groups to see if any side effects were significantly more common for the new vaccine. Because this coronavirus is widespread in the community they will also unavoidably get to collect information that would usually be the purpose of Phase II/III trials - did the group who got the "real" vaccine get COVID-19 symptoms less often that the other group? Or if they did, were they less severe? You normally don't do this, and if you tried an ethics committee would stop you - it's unethical to expose patients to a novel risk when you haven't even figured out if the treatment you're trying is safe first. But in this case the risk is already there, for absolutely everyone, so you aren't making anything worse by just measuring if your treatment helped.
- mattkrause 6y ago
  Right, but for those same reasons, a Phase I trial is usually much smaller and has “safety and tolerability” as an endpoint rather than disease-related outcomes (as this one does). I don’t think those usually have randomized control groups; see the example below. In this case, it looks like the Oxford group had previously used the same ChAdOx platform to make a MERS vaccine, and they’re leveraging that data (here: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30160-2/fulltext# https://www.thelancet.com/journals/laninf/article/PIIS1473-3...) to move more quickly into a combined Phase I and II trial.

billfruit 6y ago

And I think there are also some 4 or five vaccines in phase 1. See report https://www.nature.com/articles/d41573-020-00073-5 https://www.nature.com/articles/d41573-020-00073-5