COVID research updates: How to predict a vaccine’s success without a large trial

Moderna’s vaccine provides protection against COVID-19 by triggering the production of antibodies against a key viral protein, a study in monkeys suggests. The insight — if confirmed in humans — could speed the development of next-generation vaccines.

Vaccines can trigger diverse immune responses, including the manufacture of antibody molecules that bind and block infectious viruses, and the activation of T cells that kill virus-infected cells. By identifying the immune responses that can predict a vaccine’s success, scientists could more easily judge candidate vaccines.

To identify which immune responses are important for Moderna’s vaccine, Barney Graham and Robert Seder at the US National Institute of Allergy and Infectious Diseases in Bethesda, Maryland, and their colleagues gave monkeys a range of vaccine doses and exposed the animals to SARS-CoV-2 (K. S. Corbett et al. Preprint at bioRxiv https://doi.org/f8pf; 2021). The vaccinated animals that had the lowest levels of viral genetic material in their noses and lungs also had the highest levels of antibodies that recognize the viral spike protein, the molecule that the Moderna vaccine encodes. Levels of other immune markers did not correlate as strongly with the vaccine’s protective effects. The findings have not yet been peer reviewed.

Read the full article at: Nature