Moderna's Omicron booster vaccine shows response against subvariants in trial
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Moderna (NASDAQ:MRNA) said its bivalent (Omicron) COVID booster vaccine candidate mRNA-1273.214 showed potent neutralizing antibody responses against Omicron subvariants BA.4 and BA.5, regardless of prior infection in people in a phase 2/3 study.
The company said that one month after administration of a 50 Âµg booster dose of the vaccine, in previously vaccinated and boosted participants, there were potent neutralizing antibody responses against BA.4 and BA.5 in all participants regardless of prior infection.
The booster shot strengthened neutralizing titers against BA.4/BA.5 by 5.4-fold above baseline in all participants regardless of prior infection, and by 6.3 times in a subset of seronegative people, according to the company's June 22 press release.
Moderna, however, added that neutralizing titers against BA.4/BA.5 were ~3-fold lower than previously reported neutralizing titers against BA.1.
The company noted that neutralizing geometric mean titers (GMT) against BA.4/BA.5 were 941 in all participants, and 727 in seronegative participants; for context, prior studies of a third dose of the prototype booster induced neutralizing GMT against BA.1 of 629 and 828 against Delta. The third dose of the prototype booster was shown to be effective against Delta and BA.1 infection and hospitalization in observational studies.
"We will submit these data to regulators urgently and are preparing to supply our next generation bivalent booster starting in August, ahead of a potential rise in SARS-CoV-2 infections due to Omicron subvariants in the early fall," said Moderna CEO StÃ©phane Bancel.
Moderna (MRNA) added that based on this and prior data, it is working to complete regulatory submissions in the coming weeks, requesting to update the composition of the booster vaccine to mRNA-1273.214.