Two new studies indicate that SARS-CoV-2 vaccines from Pfizer-BioNTech and Moderna elicit a lower neutralizing antibody response against the B.1.351 viral lineage identified in South Africa, the Washington Post reports.
With the identification of new SARS-CoV-2 viral strains, there have been concerns that current vaccines could be less effective, particularly against strains with changes to the spike protein targeted by many vaccines. Clinical trial data from Novavax and Johnson & Johnson, for instance, suggested that their vaccines had lower efficacy rates when faced with the B.1.351 strain, though initial studies have suggested that the both the Pfizer-BioNTech vaccine and Moderna vaccine are effective against the new strains.
Two new analyses appearing in the New England Journal of Medicine — one from University of Texas Medical Branch, Pfizer, and BioNTech researchers and one from National Institute of Allergy and Infectious Diseases and Moderna researchers — report that the blood samples from vaccinated individuals elicit a lower neutralizing antibody response following exposure to viruses engineered to be like the B.1.351 viral lineage.
"We don't know what the minimum neutralizing number is. We don't have that cutoff line," Texas' Pei-Yong Shi tells Reuters, adding that he suspects the Pfizer-BioNTech vaccine is likely to still provide protections against the variant. Moderna, Reuters adds, has also said it thinks its vaccine is effective against the B.1.351 viral lineage