Moderna’s COVID-19 vaccine booster (mRNA-1273 50µg dose level) induced robust antibody responses of more than 40 times against the Delta variant (B.1.617.2), according to Phase 2 clinical data reported by the company.
The trial offered a booster dose of mRNA-1273 at the 50 µg dose level to interested participants 6 months following their second dose (n=344). Neutralizing antibody titers had waned significantly prior to boosting at approximately 6 months. A booster dose of mRNA-1273 at the 50 µg dose level boosted neutralizing titers significantly above the Phase 3 benchmark. After a third dose, a similar level of neutralizing titers was achieved across age groups, notably in older adults (ages 65 and above). The safety profile following dose 3 was similar to that observed previously for dose 2 of mRNA-1273. These data will be submitted to a peer-reviewed publication.
An additional analysis showed that a booster dose of mRNA-1273 at the 50 µg dose level induced robust antibody responses and significantly increased geometric mean titers (GMT) for all variants of concern including Beta (B.1.351) by 32- fold, Gamma (P.1) by 43.6-fold and Delta (B.1.617.2) by 42.3-fold.
Based on the data, Moderna initiated its submission to the US FDA for the evaluation of a booster dose of the Moderna COVID-19 vaccine (mRNA-1273) at the 50 µg dose level. The company expects to submit data to the European Medicines Agency (EMA) and other regulatory authorities around the world in the coming days.
“We are pleased to initiate the submission process for our booster candidate at the 50 µg dose with the FDA. Our submission is supported by data generated with the 50 µg dose of our COVID-19 vaccine, which shows robust antibody responses against the Delta variant,” said Stéphane Bancel, Chief Executive Officer of Moderna. “We remain committed to staying ahead of the virus and following the evolving epidemiology of SARS-CoV-2. We will continue to generate data and transparently share to support governments and regulators as they make evidence-based decisions regarding future vaccination strategies.”