That isn't always true anymore. They could get participants that are already in the hospital with a bad flu. Not all phase I's are using healthy patients these days. I was surprised to find that out. It will be great to see the actual trial design.
Either way, you are correct in that we won't see efficacy in Phase I if they use healthy patients.
In Reply to 'JG36' They can easily get through phase I for Flucide without seeing efficacy results for the simplest of reasons: Phase I trials are done on healthy people. The participants in the study won't have the flu, nor will they be given a deliberate dose of the flu.