What If Pfizer's and Moderna's Coronavirus Vaccine Results Are Delayed?

Pfizer and Moderna are the two U.S. companies likely to first announce results from late-stage testing of their respective coronavirus vaccine candidates. But what if either company's results are delayed? Believe it or not, delays could actually be great news. The FDA will probably require that participants in late-stage clinical studies of COVID-19 vaccine candidates be monitored for a median of two months after the second dose of the vaccine. In addition, the agency is expected to require that the placebo groups of the studies have at least five cases of severe COVID-19. Pfizer and Moderna can control how they meet the first of these two criteria, but if there aren't enough participants in the placebo group who develop severe cases of COVID-19, they won't be able to seek EUA. If this scenario happens, it would mean that nearly all unvaccinated individuals in the late-stage studies aren't being infected by the novel coronavirus. That would be fantastic and point to a significant improvement in how COVID-19 is impacting the country. It would also mean that Pfizer and Moderna would have more vaccinated participants to evaluate the safety profiles of their respective vaccines. This could boost Americans' confidence in the vaccines.