Sanofi and GlaxoSmithKline have reported that their candidate SARS-CoV-2 vaccine has had encouraging results in an early-stage trial, the Wall Street Journal reports.
The companies announced in April 2020 that they were working together on a SARS-CoV-2 vaccine that incorporated Sanofi's antigen-generating approach and an adjuvant developed by GSK. But in December 2020, they reported that the candidate vaccine elicited an insufficient immune response, which they traced to an issue with the concentration of the antigen.
As the Journal notes, the companies reformulated the vaccine for new trials. Now in a Phase 2 trial of 722 individuals, the companies found that their candidate SARS-CoV-2 vaccine, delivered in a two-dose regimen, generated a strong immune response. They in particular note that one dose of their vaccine led to neutralizing antibody levels similar to those seen in people who had had SARS-CoV-2 infections, which suggested to them that their vaccine could also be developed as a booster.
The companies plan to embark on a Phase 3 trial of more than 35,000 adults that will also examine the efficacy of the vaccine against variants like B.1.351.