A group from Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK, etc. has reported on neutralizing antibody responses against SARS-CoV-2 Omicron.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8723827/
Here is some presented data showing that the huge number of mutational changes present in Omicron lead to a substantial knockdown of neutralizing capacity of commercially available mAb.
“Commercial neutralizing antibody responses against SARS-CoV-2”
Degradation of neutralization titers of Omicron by sera from vaccines might be ineludible, but it is unlikely that vaccines will completely fail and it is hoped that although vaccine breakthroughs will occur, protection from severe disease will be maintained, perhaps by T cells. It is likely that the vaccine-induced T cell response to SARS-CoV-2 will be less affected than the antibody response.