Moderna Omicron BA.1 bivalent vaccine better than original shot as 4th booster
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Moderna (NASDAQ:MRNA) said its Omicron BA.1-targeting bivalent mRNA-1273.214 vaccine showed superior antibody response as fourth booster, compared to Spikevax prototype booster mRNA-1273 after three months.
The company noted that 90 days after administration as a 4th booster shot in previously vaccinated and boosted participants, a 50 Âµg booster dose of mRNA-1273.214 elicited a superior neutralizing antibody response against Omicron BA.1, compared to a 50 Âµg booster dose of mRNA-1273 in all participants regardless of prior infection.
Superior performance against Omicron BA.1 was also durable, with higher antibody titers sustained through three months, Moderna said in a statement on Wednesday.
The company added that as previously reported, bivalent vaccine showed significantly higher neutralizing antibody responses against Omicron BA.4/BA.5, compared to the original vaccine, 28 days after administration.
Responses were also seen against Omicron BA.2.75, 28 days after getting the vaccine, suggesting that the bivalent booster elicits broad cross-neutralization against Omicron variants, Moderna noted.
"Clinical trial data now indicates that the superior immune response produced by our bivalent booster has durability for at least three months," said Moderna CEO StÃ©phane Bancel.
Side effects of the bivalent shot were similar or less severe than those of either a second or third dose of the original vaccine, according to the company.
Moderna expects interim results of its Omicron BA.4/BA.5-targeting bivalent vaccine mRNA-1273.222 later this year.
MRNA -1.55% to $132.01 premarket Oct. 19