Not an expert, but creating a perennial vaccine depends on the mutation rate and which highly-conserved regions can be targeted. One of the potential vaccines

Not an expert, but creating a perennial vaccine depends on the mutation rate and which highly-conserved regions can be targeted. One of the potential vaccines enrolling trial patients is made of mRNA that codes for the spike protein needed for entry to cells. [0] If that spike protein turns out to be highly-conserved, then the vaccine will have sticking power. If it's not, but there turn out to be evolutionary trade-offs to adapting around it, it could push the virus to become less aggressive. 0. https://clinicaltrials.gov/ct2/show/NCT04283461 https://clinicaltrials.gov/ct2/show/NCT04283461