No, looks like it is easy to modify existing mRNA vaccines slightly and give booster shots

>“Every time a new variant comes up we should be able to test whether or not [our vaccine] is effective,” Pfizer CEO Albert Bourla told Bloomberg news. “Once we discover something that is not as effective, we will very, very quickly be able to produce a booster dose that will be a small variation to the current vaccine.”

https://www.google.com/amp/s/www.timesofisrael.com/pfizer-mo...