Small studies indicate Moderna COVID-19 vaccine may be effective against Delta, Kappa and Eta variants

Moderna, Inc. released a clinical update of a small Phase 1 trial this week evaluating the performance of its mRNA COVID-19 vaccine against three of the ever-multiplying strains of the disease, including the worrisome Delta variant.

Based on serum samples from eight vaccinated participants, neutralizing titers were produced against the Beta, Kappa, Delta, Eta, A.23.1, and A.VOI.V2 variants of SARS-CoV-2 — the virus that causes COVID-19. Results were submitted as a preprint to bioRxiv.

“As we seek to defeat the pandemic, it is imperative that we are proactive as the virus evolves. We remain committed to studying emerging variants, generating data, and sharing it as it becomes available. These new data are encouraging and reinforce our belief that the Moderna COVID-19 Vaccine should remain protective against newly detected variants,” Stéphane Bancel, CEO of Moderna, said. “These findings highlight the importance of continuing to vaccinate populations with an effective primary series vaccine.”

While clinical trials have been conducted against other strains, this test focused on these additional variant strains. While minimal reduction to neutralizing titers was observed on the Alpha and A.23.1 strains, a modest reduction was observed in Delta (2.1-fold), Gamma (3.2-fold), Kappa (3.3-3.4-fold), and Eta (4.2-fold). The Beta variant brought anywhere from a 7.3-8.4-fold reduction in neutralizers, but the biggest reduction outright was encountered in A.VOI.V2, which brought an 8-fold reduction.

At present, A.VOI.V2 — first identified in Angola — is not designated as a variant of concern or interest.