> Moderna is seeking 56 individuals, aged 18 to 50 and who are HIV-negative, for the trial, which is estimated to begin on August 19 and conclude in spring 2023.

Probably a dumb question given that I have little domain knowledge here, but are they really going to get valuable data from 56 individuals? Like, isn't that N really small? How many of them would be expected to contract HIV?

And, I'd imagine that if they are selecting a high-risk population for the trials (e.g., sexually active young gay men), wouldn't a lot of the individuals already be on PREP? Would they have to go off of PREP, and run a potentially much greater risk of contracting HIV if the vaccine doesn't actually work?