Omicron-Adapted Vaccines Likely to Support Our mRNA COVID-19 Booster Sales Estimates

We're not making any changes to our Moderna or Pfizer/BioNTech fair value estimates following a U.S. Food and Drug Administration advisory committee meeting on June 28 that was supportive of adapting mRNA-based COVID-19 vaccine booster shots to contain an omicron-based component. The committee voted 19 to 2 in favor of a strain change, with some members citing as part of their rationale the waning efficacy (55%, according to Centers for Disease Control and Prevention data presented at the meeting) of approved boosters against hospitalization from BA.2 omicron subvariants. Most committee members supported the use of a bivalent vaccine that would offer protection against both the ancestral (original) SARS-CoV-2 virus as well as the BA.1 subvariant of omicron, rather than switching to an omicron-adapted vaccine. Data presented by Pfizer and Moderna were generally supportive of using this bivalent approach, as duration of protection appears to be longer with such vaccines (based on six-month data from Moderna's beta-adapted bivalent program).