xav-19

XAV-19 is a glyco-humanized swine polyclonal antibody developed as an intravenous treatment targeting SARS-CoV-2, the virus responsible for COVID-19. It is produced by immunizing genetically modified pigs (double knockout for alpha 1,3-galactosyltransferase and cytidine monophosphate-N-acetylneuraminic acid hydroxylase) with the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. The resulting polyclonal IgG fraction targets multiple epitopes on the RBD, particularly those involved in binding to human ACE2 receptors. This broad epitope recognition allows XAV-19 to maintain neutralizing activity against various SARS-CoV-2 variants, including Alpha, Beta, Gamma, Delta, and Omicron subvariants[1][6][7]. Clinical trials have shown that while XAV-19 did not significantly reduce disease aggravation in hospitalized COVID-19 patients overall or benefit those requiring oxygen therapy, it accelerated recovery time in patients with mild to moderate disease not requiring oxygen[1][5]. The drug was well tolerated but its development was discontinued after phase II/III trials due to slow enrollment and lack of significant efficacy on primary endpoints[4].