In a statement Moderna Inc said, a booster dose of its COVID-19 vaccine appears to protect against the fast-spreading Omicron variant of COVID-19 in laboratory tests; its current version of the vaccine will continue to be its “first line of defense against Omicron.”
Moderna went on to add, its decision to focus on the current vaccine, mRNA-1273, was driven in part by how quickly Omicron was spreading across the globe.
Nevertheless, it still plans on developing a vaccine to protect against the Omicron variant specifically and aims to start clinical trials in early 2022.
“What we have available right now is 1273,” said Dr. Paul Burton, Moderna’s chief medical officer. “It’s highly effective, and it’s extremely safe. I think it will protect people through the coming holiday period and through these winter months, when we’re going to see the most severe pressure of Omicron.”
Modern said, while two doses of its vaccine generated low neutralizing antibodies against the Omicron variant, but a 50-microgram booster dose increased neutralizing antibodies by 37 times. A 100-microgram booster, the same strength as the original shots, drove neutralizing antibodies to more than 80 times pre-boost levels.
In a press conference, Moderna President Stephen Hoge said, the company does not currently plan on pursuing approval for the higher booster dose.
“The antibody levels generated by the lower dose shot “are comfortably above” what would signify a risk of breakthrough infections for other variants of concern,” said Hoge.
Incidentally, Moderna did not specifically mentioned whether it believes its two-dose vaccine regimen will reduce hospitalizations or deaths from the Omicron variant.
Studies by other researchers have shown a “reasonable and robust” T cell response is maintained against the variant, said Hoge, which could suggest protection against severe disease.
T cells in the immune system recognize and eliminate virus-infected cells.
The new data, has yet to be peer reviewed, tested blood from those who had received Moderna’s vaccine against a pseudovirus engineered to resemble the Omicron variant.
While “it may not be necessary to push antibody levels higher than those generated by the 50-microgram dose for many people,” said Hoge, “governments could, however, choose a higher-dose version if they want to confer an enhanced level of protection”.
“The 100-microgram dose was generally safe and well tolerated, although there was a trend toward slightly more frequent adverse reactions.”
In October, the FDA authorized the 50-microgram booster of Moderna’s vaccine.
Moderna and the Pfizer/BioNTech vaccines have been linked to rare cases of heart inflammation, especially in young men.
Several studies have suggested that Moderna’s vaccine is likely to cause the heart inflammation at a higher rate than Pfizer’s.