Moderna, Inc. announced new results from in vitro neutralization studies of sera from individuals vaccinated with the Moderna COVID-19 Vaccine showing activity against variants of SARS-CoV-2.
Vaccination with the Moderna COVID-19 Vaccine produced neutralizing titers against all variants tested, including additional versions of the Beta variant (B.1.351, first identified in South Africa), three lineage variants of B.1.617 (first identified in India), including the Kappa (B.1.617.1) and the Delta variants (B.1.617.2); the Eta variant (B.1.525, first identified in Nigeria); and the A.23.1 and A.VOI.V2 variants first identified in Uganda and Angola, respectively. These data were submitted as a preprint to bioRxiv.
The study methodology was previously described in the letter to the editor published in NEJM on April 15, 2021 concerning the variants first identified in the U.K. (Alpha, B.1.1.7) and the Republic of South Africa (Beta, B.1.351) using serum samples from eight participants obtained one week after participants’ second dose of the primary series in the Phase 1 clinical trial of the Moderna COVID-19 Vaccine. These most recent data include neutralization assays against additional variant strains. This additional analysis showed minimal impact on neutralizing titers against the Alpha and A.23.1 variants relative to those against the ancestral strain (D614G). This analysis also showed a modest reduction in neutralizing titers against the Delta (2.1-fold), Gamma (P.1, 3.2-fold), Kappa (3.3-3.4-fold), and Eta (4.2-fold) variants relative to those against the ancestral strain. Consistent with previous results, a 7.3 or 8.4-fold reduction in neutralizing titers was observed with the additional versions of the Beta variant relative to the ancestral strain. Additionally, an 8.0-fold reduction in neutralizing titers relative to the ancestral strain was observed with A.VOI.V2, the variant first identified in Angola, but currently not designated as a Variant of Concern or Interest.
Moderna is pursuing a clinical development strategy against emerging variants to proactively address the pandemic as the virus continues to evolve. The Company is also studying mRNA-1273.211, a multivalent booster candidate which combines a 50-50 mix of mRNA-1273, Moderna’s authorized vaccine against ancestral strains, and mRNA-1273.351 in a single vaccine at several dose levels in an ongoing study.
