I wonder what will happen with the vaccine deals that governments have been doing. Like, what if they pre-ordered from one manufacturer whose vaccine proves inferior to the other ones?
That said, all the deals are contingent on being effective. With this being 90% effective that sets a bar for the others. The FDA has previously said they need your vaccine to be 50% effective to approve it. However with this being 90% effective they are unlikely to approve one that is only 50% effective. Unlikely doesn't mean they won't: different allergic reactions; usefulness in different age groups; ability to ship to remote groups; difference in effectiveness to some minority: all are factors that may make some vaccine approved even if it is clearly the worse one to get overall.