Moderna: said Monday that its Covid-19 booster does appear to provide protection against the omicron variant that is currently surging across the world.
Preliminary data from lab testing found that the version of its booster currently in use in the United States and elsewhere provided increased antibody levels to neutralize the virus, Moderna said. But it also found that a double dose of the booster shot provided a much greater increase in those levels.
Pfizer said last week that a booster dose of its COVID-19 vaccine may offer important protection against the new omicron variant even though the initial two doses appear significantly less effective.
Pfizer and its partner BioNTech said that while two doses may not be protective enough to prevent infection, lab tests showed a booster increased by 25-fold people’s levels of virus-fighting antibodies.
Blood samples taken a month after a booster showed people harbored levels of omicron-neutralizing antibodies that were similar to amounts proven protective against earlier variants after two doses.
Moderna, of Cambridge, Mass., said the authorized dosage of its booster shot increased levels of immune-system agents known as neutralizing antibodies against Omicron about 37 times pre-boost levels.
Neutralizing antibodies are among the first soldiers that the immune system deploys to battle invaders like the coronavirus.
“What we showed is when you boost, you get a good brisk increase in antibody levels and they would be correlated with protection,” Moderna Chief Medical Officer Paul Burton said in an interview.
The authorized booster shot is half the dose level used for each of the first two shots of the vaccine.
In an announcement early Monday, the drug company said preliminary data from lab testing found the version of its booster currently in use in the United States and elsewhere provided increased antibody levels to neutralize the virus. But it also found that a double dose of the booster shot provided a much greater increase in those levels.
The drug company said its currently FDA-approved 50 microgram booster was found to increase neutralizing antibody levels against omicron 37-fold compared to pre-boost levels. Meanwhile, it found that a 100 microgram booster dose gave an 83-fold increase in neutralizing antibody levels.
The currently authorised 50-microgram booster of Moderna’s Covid-19 vaccine mRNA-1273 increased neutralising antibody levels against Omicron about 37-fold compared to pre-boost levels, and a 100-microgram booster dose increased neutralising antibody levels about 83-fold, Xinhua news agency quoted the company as saying.
A 100-microgram booster dose was “generally safe and well-tolerated,” according to the company. But there was a trend toward slightly more frequent adverse reactions following the 100-microgram booster dose relative to the authorised 50-microgram booster dose, said the company.
The omicron variant, discovered late last month, carries an unusually large number of mutations and scientists are racing to learn how easily it spreads, whether it causes illness that is more serious or milder than other coronavirus types — and how much it might evade the protection of prior vaccinations.
In a small preliminary study out of South Africa, where the omicron variant was first detected, scientists said the variant significantly reduces antibody protection generated by Pfizer and BioNTech‘s vaccine, although people who have recovered from the virus and received a booster shot will likely have more protection from severe disease.