Simple logic applies, take the Alzheimer's trial for example.
1/3 are on placebo.
Alzheimer's patients don't get better.
If half or more of the trial patients start to show marked improvement (like sleeping better and becoming more responsive) something is happening that has never happened before.
Since the only thing that is different is the trial medicine, simple logic would indicate that the medicine is getting better.
You raise an interesting question. The trial participants in the 2a were all getting 2-73 and continue to receive it as the trial was extended.
That suggests to me that none of them can be subjects in the new trial since they can not be assigned to the placebo group. Therefore they would be unblinded.
It is still unclear to me what dosages the remaining 2a subjects are receiving. I recall this has been discussed but no longer remember if the answer is known.
India....This discussion about the need for blinded, placebo control trials has gone on for several years. The more current 21st CCA guidance points to the options of using "unblinded", non placebo trials when there is ample safety and "Natural History" data available for the trial. This also requires an unmet need for critical medical applications. Both Scott Gottlieb and Janet Woodcock have moved the FDA in this direction in order to get drugs, especially cancer drugs, to market more quickly. Below, is Dr Woodcock's testimony to Congress on modern 2!stCCA clinical trial architecture.
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