yes i agree an important data point not yet publis
Post# of 149059
Both the Moderna and Biontech/Pfizer trials have an interim analysis specified at the point at which 94 (or something like that, I don't know the exact number) trial participants have contracted covid19.
At that interim point, I think "effectiveness"=(vaccinated_covid)/(vaccinated_covid + placebo_covid)
Probably the interim analysis happens as soon as they hit the interim number of covid cases, regardless of how many trial participants have been vaccinated