Moderna study shows hope in the fight against rapid Covid-19 mutations

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New data from

Modern

shows a way in which messenger RNA-based vaccines may be able to keep up with the rapidly mutating virus that causes Covid-19.

An experimental Moderna Covid-19 booster that blends the original vaccine with a version designed to specifically protect against the Beta variant provided better protection than the original booster against Omicron, the company said. Tuesday.

The study measured immune responses to the experimental vaccine, which Moderna (ticker: MRNA) called mRNA-1273,211, after one month and after six months. The company said that after one month, a dose of mRNA-1273,211 of similar size elicited a stronger antibody response to the Beta, Delta and Omicron variants than the original booster.

After six months, mRNA-1273,211 elicited a stronger response against Beta and Omicron, but not against Delta.

A major concern about updated versions of the Covid-19 vaccines has been that even the rapid updates made possible by the messenger RNA technology that Modern uses may not be fast enough to keep up with the virus that causes Covid -19. However, new data suggesting that the beta-specific bivalent vaccine provides better protection against Omicron than the original vaccine provides some evidence that, although the bivalent vaccine does not target exactly the right variant, it may still offer better protection than the original. vaccine.

It is a statement of confidence in the long-term usefulness of mRNA-based vaccines to protect against the rapidly changing virus.

“We believe these results validate our bivalent strategy,” Moderna CEO Stéphane Bancel said in a statement. “The results indicate that mRNA-1273,211 at the 50 µg dose level induced higher antibody responses than the 50 µg mRNA-1273 booster, even when additional variants of concern were not included in the booster vaccine.”

The data comes as the Food and Drug Administration considering whether an expected booster campaign this fall would involve an updated version of the Covid-19 vaccines or the same versions of the vaccines that have been used so far. Moderna said they do not expect to use mRNA-1273,211 this fall, but instead plan to use another version, called mRNA-1273.214, which combines an Omicron-specific booster with the original vaccine. The company said it would have data on mRNA-1273,214 later in the second quarter.

Moderna shares fell 2.3% on Tuesday and fell 40.5% this year.

On Tuesday, Moderna published a paper that has not yet been peer reviewed, describes The study. The research involved nearly 900 people who had previously received two doses of Moderna’s original vaccine, of which 300 received a dose of 50 micrograms and nearly 600 of them received a dose of 100 micrograms.

Adverse reactions were higher in the larger dose group. The authors of the paper wrote that the reactions to the smaller dose were comparable to the equivalent size of the original vaccine.

The authors of the paper concluded that mRNA-1273,211 “elicited robust and persistent antibody responses to several variants of concern, even when some of these variants were not included in the vaccine.”

The ability to neutralize multiple variants, they wrote, “seems to be the benefits of bivalent booster vaccines that contain both ancestral SARS-CoV-2 and variant peak sequences, and such vaccines may represent an important strategy when we respond. on new SARS-CoV -2 variants. “

Write to Josh Nathan-Kazis at [email protected]