According to the company, Moderna’s new Covid booster elicited a stronger immune response against omicron BA.5 and also appears to work against an emerging sub-variant of BQ.1.1.
Art Nouveau, in clinical trial data released on Monday, the new booster vaccine was found to elicit five times more anti-omicron BA.5 antibodies than older vaccines in people with previous Covid infections. The boosters produced more than six times more anti-BA.5 antibodies in people without previous infections.
The study involved 500 people aged 19 to 89 who received a new booster. This is the first human data that Moderna has published on boosters.
Moderna said it also found that the new booster elicited a strong immune response against microbial BQ.1.1, a new U.S. sub-variant of Covid. However, the response was not as strong against BQ.1.1 as compared to BA.5. Antibody levels were about five times lower against BQ.1.1.
The FDA asked Moderna and Pfizer to develop boosters against omicron BA.5 during the summer when it was dominant. But other omicron sub-options are replacing BA.5 just a couple of months after US health regulators approved the boosters.
According to the Centers for Disease Control and Prevention, Omicron BA.5 currently accounts for 29% of new infections in the US, while sub-variants BQ.1 and BQ.1.1 account for 44% of new cases in the US. U.S. health officials have stated that boosters should provide protection against BQ sub-variants as they are descended from BA.5.
Pfizer also released data earlier this month indicating boosters provide better protection against omicron BA.5 than older shots.
Public interest in booster data is high because the FDA allowed them without direct human data on how they work. Instead, the agency relied on data from clinical trials of a similar booster targeting omicron BA.1, the original version of omicron that caused a massive surge last winter.
Pfizer and Moderna were originally developing boosters against omicron BA.1, but the FDA asked them to switch and target BA.5 instead, as the sub-variant became dominant over the summer. The sudden change did not leave enough time for companies to launch clinical trials and submit data on BA.5 boosters before getting approval.
Two independent studies conducted at Columbia and Harvard Universities found that boosters did not do much better with omicron BA.5. The FDA objected to these studies, arguing that they were too small to draw definitive conclusions about vaccines.
The new boosters, called bivalent vaccines, target both omicron BA.5 and the original version of Covid, which appeared in China in 2019. The old vaccines, called monovalent vaccines, only target the original version of Covid.
The effectiveness of the old vaccines against infections and minor illnesses has declined sharply as the virus has mutated further and further away from the original strain. Older vaccinations still provide protection against serious illness, although that protection is also declining.
US health officials hope the new boosters will help prevent another massive wave of illnesses this winter.