The Psychology of Trading, page-642

I thought the entire purpose of a potency assay was to ensure there was no difference in product delivered to the treatment group.

If looking to confirm this, you can use the entire group including those that had multiple lots from differing donors.

Although the number may be low in proving the 11 singe donor patients correlate, for the purpose of proving weather donors rather than INF2raplha is responsible, if the results correlate between the 11 and the total group, then case is closed.

That would place the FDA in the situation where the evidence provided correlates, and accelerated approval would be appropriate to expand the numbers in a confirmatory study in my opinion.