|Articles|January 25, 2021

Moderna Vaccine Offers Protection Against New COVID-19 Variants

However, there is a six-fold reduction in neutralizing titers in the B.1.351 variant from South Africa, so the company is exploring strategies aimed against new variants.

Moderna announced today its mRNA-1273 COVID-19 vaccine does produce neutralizing titers against the B.1.1.7 (UK variant) and B.1.351 (South Africa variant). However, the company said there is a six-fold reduction in neutralizing titers in the latter variant.

While this is significant, Moderna reported the neutralizing titer levels with B.1.351 remain above levels that are expected to be protective.

“As we seek to defeat the COVID-19 virus, which has created a worldwide pandemic, we believe it is imperative to be proactive as the virus evolves. We are encouraged by these new data, which reinforce our confidence that the Moderna COVID-19 vaccine should be protective against these newly detected variants,” Moderna CEO Stéphane Bancel, said.

Nonetheless, the company is moving forward with strategies aimed at addressing the new variants.

For example, Moderna is advancing an emerging variant booster candidate, mRNA-1273.35, against the South African strain. The mRNA-1273.351 candidate will be going into preclinical studies and a phase 1 study in the US to evaluate the immunological benefit of boosting with strain-specific spike proteins. 

“Out of an abundance of caution and leveraging the flexibility of our mRNA platform, we are advancing an emerging variant booster candidate against the variant first identified in the Republic of South Africa into the clinic to determine if it will be more effective to boost titers against this and potentially future variants,” Bancel said.

The company is also planning to study the ability to further increase neutralizing titers against emerging strains beyond the existing primary vaccination series. Moderna will test an additional booster dose of its existing COVID-19 vaccine, mRNA-1273, to study the ability to further increase neutralizing titers against emerging strains beyond the existing primary vaccination series.

The company expects that its mRNA-based booster vaccine—whether mRNA-1273 or mRNA-1273.351—will be able to further boost neutralizing titers in combination with all of the leading vaccine candidates.


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