The Pfizer vaccine can still target a key mutation in two new coronavirus variants, laboratory studies show. However, this is only one of many mutations found in the new forms of the virus.
So while the study has been welcomed, it is not seen as definitive scientific evidence about how the vaccine will perform.
New variants were detected in the UK and South Africa. Both are spreading more quickly, raising questions over what level of protection vaccines can offer against them.
The widely held view is that vaccines will still work, but researchers are looking for proof.
The study by the University of Texas focuses on a mutation called N501Y, which emerged in both new variants.
This is thought to be important because it is in the part of the virus that makes first contact with our body’s cells and changes could make it easier to get in and cause an infection.
The results showed the immune systems of vaccinated patients were able to take out the new mutation.