Emergence of SARS-CoV-2 Spike Escape Mutation Q493r After Bamlanivimab/Etesevimab Treatment for COVID-19

SARS-CoV-2 variants are usually a consequence of random mutations in humans or other hosts, but accelerated evolution can also occur under selective pressure from therapeutic interventions with neutralizing antibodies1. Bamlanivimab has been recently withdrawn from the vendor as a monotherapy because of failure against E484K-positive SARS-CoV-2 variants, but emergency use authorization remains in place for the bamlanivimab/etesevimab cocktail2, for which no completely resistant variant has been reported to date. We report here the first in vivo case of a Spike escape mutation conferring combined resistance to both bamlanivimab and etesevimab.