Moderna has reported findings from a Phase II/III clinical trial where bivalent Omicron-targeting booster candidates, mRNA-1273.214 and mRNA-1273.222, met the primary endpoint of superiority against Omicron BA.4/BA.5 variants versus the mRNA-1273 booster.
mRNA-1273 is the prototype vaccine of the company.
According to the trial findings, both bivalent shots met non-inferiority immunogenicity criteria to the initial SARS-CoV-2 strain.
In 511 subjects aged 19 to 89 years, who were vaccinated and boosted previously, a 50µg booster dose of mRNA-1273.222 induced a superior neutralising antibody response against Omicron BA.4/BA.5 variants versus a 50µg booster dose of mRNA-1273.
For subjects with and without a Covid-19 pre-booster, the Omicron BA.4/BA.5 geometric mean titer (GMT) ratios of mRNA-1273.222 and mRNA-1273 were 5.11 and 6.29, respectively.
mRNA-1273.214’s 50µg booster dose also induced a neutralising antibody response against Omicron BA.1 and Omicron BA.4/BA.5 superior to the mRNA-1273 booster, with this effect continuing through a minimum of three months.
As per data from an exploratory assessment of nearly 40 subjects, both bivalent vaccines showed strong neutralising activity against BQ.1.1, an emerging viral variant.
For mRNA-1273.214 and mRNA-1273.222, the frequency of adverse reactions was found to be in line with, or less than, that of either a second or third original vaccine dose.
Moderna CEO Stéphane Bancel said: “We are pleased to see that both of our bivalent booster vaccine candidates offer superior protection against Omicron BA.4/BA.5 variants compared to our original booster, which is encouraging given Covid-19 remains a leading cause of hospitalisation and death globally.
“In addition, the superior response against Omicron persisted for at least three months after the mRNA-1273.214 booster.
“Our bivalent boosters also show, in research assays, neutralising activity against BQ.1.1, an increasingly dominant emerging variant, confirming that updated vaccines have the potential to offer protection as the virus continues to evolve rapidly to escape our immunity.”
In June this year, the company dosed the first subjects in a Phase III trial of its seasonal influenza vaccine candidate, mRNA-1010.
Cell & Gene Therapy coverage on Clinical Trials Arena is supported by Cytiva.
Editorial content is independently produced and follows the highest standards of journalistic integrity. Topic sponsors are not involved in the creation of editorial content.