This is extremely misleading. The amount of tris in a single vaccine dose is miniscule compared to a therapeutic dose used as an alkalinizing agent.
Would you be able to comment on the applications as a stabilizing agent? Also, is it common for the formulation to be changed between when the (very small and abbreviated) trials are completed and a vaccine is widely administered?
Fear mongering nonsense. The Moderna vaccine contained tromethamine as an excipient from the beginning.