Analysis of SARS-CoV-2 Omicron Neutralization Data up to 2022-01-28

Abstract

The rapid spread of the Omicron SARS-CoV-2 variant (B.1.1.529) resulted in international efforts to quickly assess its escape from immunity generated by vaccines and previous infections. Numerous laboratories published Omicron neutralization data as preprints and reports. The understandable limitations and variability in such rapid reporting of early results however made it difficult to make definitive statements about the data. Here, we aggregate and analyze Omicron neutralization data from 23 reporting laboratories up to 2021-12-22. There are enough data to identify multiple trends and make two definitive points. First, in twice-vaccinated individuals, titer fold drop of Omicron relative to wild type is more than 19x, likely substantially more given the number of measurements below the limit of detection of the assay. Second, out to one month post third vaccination with an mRNA vaccine, or twice vaccinated after an earlier infection, the titer fold drop to Omicron is substantially less at approximately 7x. This substantially lower fold drop and somewhat higher titers after 3rd vaccination are strong early evidence for the utility of booster vaccination.

Protection of COVID-19 vaccination and previous infection against Omicron BA.1, BA.2 and Delta SARS-CoV-2 infections

“…In vitro assays have shown largely reduced neutralisation of the Omicron variant with convalescent sera or sera of vaccinated individuals [6]. Early studies on vaccine effectiveness showed very limited protection of primary COVID-19 vaccination against Omicron infection [7].…”

Susceptibility of SARS-CoV-2 Omicron Variants to Therapeutic Monoclonal Antibodies: Systematic Review and Meta-Analysis

“…The two main types of virus preparation employed in the studies reviewed here were pseudotyped and authentic virus assays. A previous meta-analysis of the neutralizing susceptibility of Omicron to the polyclonal Abs in the plasma from convalescent and/or vaccinated individuals reported that pseudotyped virus assays yielded twoto-three times higher geometric mean titers compared with authentic virus assays for certain subpopulations [50].…”

“Is Omicron mild”? Testing this narrative with the mutational landscape of its three lineages and response to existing vaccines and therapeutic antibodies

“…Due to the presence of many mutations with known immune evasion potential in Omicron genome, data on neutralization of Omicron, vaccine effectiveness (VE) and immunogenicity comparisons by convalescent and other vaccine sera in homologous prime or homologous/heterologous prime‐boost settings has been released by many research groups from more than 25 different countries. 9 , 20 , 22 , 26 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 A variety of neutralization assays and cell types including in vitro pseudo virus, live virus and real‐life datasets have been used in these studies.…”

“…49 , 53 , 65 , 86 , 88 , 89 , 90 Many vaccine combinations have been tested for tolerance and efficacy analysis in a heterologous prime‐ boost regime including inactivated virus vaccine + recombinant protein vaccine/mRNA vaccine/adenovirus vector vaccine/protein subunit vaccine or adeno‐virus vector vaccine + mRNA vaccines. 22 , 51 , 54 , 57 , 68 , 69 , 71 Following combinations of the currently approved vaccines have been included in the trials or cohort studies. The studies have tested two‐doses of inactivated vaccines BBIBP‐CorV or CoronaVac + mRNA vaccines BNT162b2 or mRNA‐1273 51 , 69 , 71 , 91 adeno‐virus vector vaccine ChAdOx1 nCoV‐19/Ad26.COV2.S + mRNA vaccine BNT162b2/mRNA 1273, 63 , 72 , 89 Inactivated virus vaccine CoronaVac/BBIBP‐CorV + recombinant protein vaccine ZF2001/NVSI‐06‐07, 54 Inactivated virus vaccine CoronaVac + adenovirus‐vector vaccine Convidecia 54 ; Inactivated vaccines BBIBP‐CorV + Protein subunit vaccine ZF2001, 53 adenoviral viral vector vaccine SputnikV + Sputnik Light Booster.…”