Using its yeast display system, AvantGen has identified a panel of high affinity human monoclonal antibody clones that bind to two distinct epitopes on the receptor-binding domain of the SARS-CoV-2 spike protein. Once bound, they block the spike protein from interacting with the angiotensin-converting enzyme 2 (ACE2) to prevent virus-induced cell-killing.

They also found that one group of antibody clones can block ACE2's interaction with SARS-CoV-1, indicating that the epitope recognized by this group of clones is conserved between SARS-CoV-1 and -2, potentially conferring broader neutralizing activity against this family of coronaviruses.

Under the agreement, AvantGen grants IGM Biosciences the rights to convert the antibody clones into immunoglobulin A (IgA) or IgM format for further development for the treatment of COVID-19. AvantGen received an upfront payment of an undisclosed amount from IGM Biosciences and is eligible to receive milestone and royalty payments.