I see many people say that we should have done vaccine challenge trials, that would have been so much quicker. But we did challenge trials. They were “approved” in September and actually begun in February. If you want fast trials, it makes just as much sense to demand that the regulators run regular trials fast. There is much more to gain on that front.
The actual efficacy trials only took about 2 months* that would have been saved by challenge trials. Most of the time was spent not studying vaccines, but waiting for approval to move on to the next step of the trial, just as all a year was spent waiting for approval for challenge trials. The criterion for moving from phase 2 to phase 3 is very simple and should not have taken any time at all, nor any explicit permission. It is perfectly reasonable for regulators to not want to trust the drug companies, but they can check the data after the fact. And if there are analyses that they did not foresee, they can do those after the new trials has already begun.
* The amount of time for efficacy in a non-challenge trial depends on the prevalence of the disease. The actual duration of 2 months was not predicted ahead of time. The FDA’s late addition of 2 months of safety data suggests that it was surprised how fast the efficacy data came in. Also, challenge trials don’t provide safety data, only efficacy. It’s good to separate safety from efficacy and make an explicit decision, a decision that the FDA tried to avoid for half of the trial. When people say that challenge trials save time, they are ignoring this, implicitly endorsing no such medium-term safety data. That’s probably the right choice, but people who make it should say it loud, not dodge responsibility like the FDA.
I see many people say that we should have done vaccine challenge trials, that would have been so much quicker. But we did challenge trials. They were “approved” in September and actually begun in February. If you want fast trials, it makes just as much sense to demand that the regulators run regular trials fast. There is much more to gain on that front.
The actual efficacy trials only took about 2 months* that would have been saved by challenge trials. Most of the time was spent not studying vaccines, but waiting for approval to move on to the next step of the trial, just as all a year was spent waiting for approval for challenge trials. The criterion for moving from phase 2 to phase 3 is very simple and should not have taken any time at all, nor any explicit permission. It is perfectly reasonable for regulators to not want to trust the drug companies, but they can check the data after the fact. And if there are analyses that they did not foresee, they can do those after the new trials has already begun.
* The amount of time for efficacy in a non-challenge trial depends on the prevalence of the disease. The actual duration of 2 months was not predicted ahead of time. The FDA’s late addition of 2 months of safety data suggests that it was surprised how fast the efficacy data came in. Also, challenge trials don’t provide safety data, only efficacy. It’s good to separate safety from efficacy and make an explicit decision, a decision that the FDA tried to avoid for half of the trial. When people say that challenge trials save time, they are ignoring this, implicitly endorsing no such medium-term safety data. That’s probably the right choice, but people who make it should say it loud, not dodge responsibility like the FDA.