"On 7 January 2021 it was reported that Pfizer researchers had found the Pfizer and BioNTech COVID-19 vaccine in tests involving 20 blood assays to be capable of affording protection against one of the 501.V2 variant mutations (N501Y, shared with variant B1.1.7). Further investigation was to be undertaken to ascertain the level of protection involved."
The next section in the article is what's important here:
E484K mutation
The E484K amino acid change, a receptor-binding-domain (RBD) mutation, was reported to be "associated with escape from neutralising antibodies" which could adversely affect the efficacy of spike protein-dependent COVID vaccines.[50][51] The E484K spike mutation was linked to a case of reinfection with the 501.V2 variant of SARS-CoV-2 in Brazil, believed by researchers to be the first such case of reinfection involving this mutation.[29] The possibility of an alteration in antigenicity was referred to as an "escape mutation" from a monoclonal antibody with the capability of neutralising the spike protein variants of SARS-CoV-2.[52][53]
I read that. They're only speculating that this could impact vaccines that rely on the spike protein. They didn't actually test for that.
The links I posted show that testing with current mRNA vaccines against this exact variant are under way. Pfizer's (very small) initial tests results seem positive.
E484K mutation The E484K amino acid change, a receptor-binding-domain (RBD) mutation, was reported to be "associated with escape from neutralising antibodies" which could adversely affect the efficacy of spike protein-dependent COVID vaccines.[50][51] The E484K spike mutation was linked to a case of reinfection with the 501.V2 variant of SARS-CoV-2 in Brazil, believed by researchers to be the first such case of reinfection involving this mutation.[29] The possibility of an alteration in antigenicity was referred to as an "escape mutation" from a monoclonal antibody with the capability of neutralising the spike protein variants of SARS-CoV-2.[52][53]