> Two of those companies, Moderna and Pfizer, are now in Phase 3, large-scale clinical trials. The 30,000 volunteers in each of the trials are getting two doses, with Moderna spacing their shots out 28 days apart and Pfizer spacing theirs out by 21 days.
> AstraZeneca is expected to start Phase 3 trials this month. Their Phase 1 and Phase 2 trials used two doses given 28 days apart.
Can you also share some of those sources you mention? Thanks!