Vaccine updated for Omicron, when it arrives and how it works

Bancel (Moderna): “More lasting protection, hopefully available at the end of summer”

It could arrive at the end of the summer on Covid vaccine updated to Omicron variants of Sars-Cov-2. Moderna announces it, illustrating some promising results of the phase 2/3 study that “met all the primary endpoints” set for the trial.

A 50 microgram booster of the bivalent anti-Covid booster candidate (mRNA-1273.214) “demonstrated, one month after administration – explains the pharmaceutical company – a superior response in terms of antibodies against the Omicron variant of Sars-CoV-2 compared to Moderna’s original vaccine (mRNA-1273) “.

We are thrilled to share the preliminary analysis of data on mRNA-1273.214 “which” represents an innovation in the fight against Covid “, explained in a statement Stéphane Bancel, CEO of Moderna.” We are submitting our preliminary data and our analyzes to the regulatory authorities with the hope that the bivalent booster containing Omicron will be available in late summer “.

“Looking at these data – underlined Bancel – together with the durability we saw with our first bivalent booster candidate, mRNA-1273.211, we expect longer lasting protection against variants of concern with mRNA-1273.214, making it our prime candidate for the recall of autumn 2022Taken together, concludes the US company manager, “our bivalent booster candidates demonstrate the power of Moderna’s mRna platform in developing vaccines that respond rapidly to global public health threats.”

How mRNA-1273.214 works

In detail, Moderna’s bivalent booster candidate contains the already approved Spikevax * vaccine and a vaccine candidate targeting the Omicron variant. A booster dose of 50 µg of mRNA-1273.214 was “generally well tolerated” in the 437 study participants, with side effects comparable to a booster dose of mRNA-1273 “, the vaccine already in use,” at the dose level of 50 µg “.

The criteria for evaluating the superiority of the booster candidate were met, explains Moderna. A booster dose of mRNA-1273.214 increased the geometric mean of neutralizing titers (Gmt) compared to Omicron by “approximately 8-fold of baseline levels”. And “the primary endpoints of non-inferiority against ancestral Sars-CoV-2 have also been achieved”. Among seronegative participants one month after dosing, the ancestral Gmt against Sars-CoV-2 for the booster candidate was 5,977, compared to the Spikevax vaccine’s Gmt of 5,649. Against Omicron the GMT was 2,372 compared to 1,473 for the approved vaccine. The binding antibody titers (Msd) were also “significantly higher than all other variants of interest (Alpha, Beta, Gamma, Delta, Omicron) for mRNA-1273.214”.

The results of the other beta-containing bivalent booster candidate, i.e. mRNA-1273.211, announced in April 2022, demonstrated superiority against the Beta, Delta and Omicron variants one month after administration; this was durable against the Beta and Omicron variants 6 months after administration. “Given the significantly higher antibody titers induced by mRNA-1273.214 compared to mRNA-1273,” Moderna predicts that the antibody titers induced by the Omicron-targeted booster, “mRNA-1273.214, will be more durable against Omicron than mRNA-1273. “. Moderna will report data from day 91 after vaccination later in the summer and plans to submit interim analysis and data to regulatory authorities for review in the coming weeks.