There was a link to another document on this guidance which will be published Monday, 3/27. Here is a clip. It looks to me like Moderna can get approval on the P2 data (assuming effective and safe enough) if their confirmatory trial is fully enrolled. If so, it's great news.
" Given the limitations of single-arm trials, FDA considers a randomized controlled trial to be the most appropriate trial design to support accelerated approval of oncology drugs. When properly designed and executed, a randomized controlled trial provides a more robust efficacy and safety assessment and allows for direct comparisons to a concurrent control arm. Sponsors can, as appropriate, elect to conduct a single randomized controlled trial to support an accelerated approval and to verify clinical benefit (i.e., follow the “one-trial” approach), or they can conduct separate trials--one to support the accelerated approval and another, a confirmatory trial, to verify clinical benefit. The “one-trial” approach maintains efficiency in drug development by providing early access to an investigational drug using the accelerated approval pathway, while ensuring that a postmarketing trial is fully accrued and well underway to verify longer term benefit in a timely fashion. "