I agree it would be better in the end after it’s approved. I’m thinking about getting the ethics board to allow a trial where you have to give half of the participants a control (and the other half a possibly-ineffective vaccine), when a known-good alternative exists.

The other reply has a solid point. Maybe you can find a country where it’s not possible to distribute daily PrEP, but is possible to vaccinate people and then test them for HIV monthly.