Moderna and rival Pfizer are developing updated vaccines to target the fast-spreading Omicron subvariants BA.4 and BA.5, which have gained a foothold in the US, among other countries, over recent weeks.
Moderna said its decision to develop the bivalent vaccines was based on different market preferences for shots against the subvariants, reports Reuters.
Bivalent vaccines are designed to target two different coronavirus variants – the original variant from 2020 and the newer Omicron variants.
Moderna said new clinical data for its mRNA-1273.214 vaccine, designed to target the BA.1 variant, showed significantly higher neutralising antibody responses against the fast-spreading BA.4 and BA.5 compared with the currently authorised booster.
The company's second booster candidate, mRNA 1273.222, is based on the BA.4/5 strain and is being developed in accordance with recent US Food and Drug Administration (FDA) advice.
Jefferies analyst Michael Yee said though the new data on the company’s BA.1 subvariant-targeting booster shows better durability and antibody response, the original Omicron variant has already shifted in the US and the FDA is likely to approve planned BA.4/5 boosters.
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NICD statistics: COVID cases rise as two Omicron sub-lineages spread across SA
Tests and wastewater analyses signal a possible 5th wave in SA
Pfizer and Moderna fare better against variants of concern – Dutch research