The first results of an early trial of a multivariant COVID-19 vaccine booster, launched in Manchester in September 2021, has shown it is driving a comprehensive immune response.
U.S.-based biotechnology company Gritstone bio, Inc. in collaboration with The University of Manchester and Manchester University NHS Foundation Trust today (4 January 2022) reveal the initial phase one clinical data shows the vaccine has strong levels of neutralizing antibodies, similar to approved mRNA vaccines, but at up to a 10-fold lower dose in the first 10 individuals.
Results also show the vaccine, which is being trialed with the anticipated involvement of 20 people aged 60 and over, who were in good health and previously received two doses of AstraZeneca's first-generation COVID-19 vaccine, was generally safe and well-tolerated.
Part of Gritstone's CORAL program, the compound is a self-amplifying mRNA second generation SARS-CoV-2 vaccine—or samRNA for short—which delivers antigens from both spike and non-spike proteins.
The samRNA vaccine also produced broad CD8+ T cell responses against targets from conserved SARS-CoV-2 viral proteins and boosted spike-specific T cells.
Based on results, the trial is now being expanded to 120 people, potentially enabling more rapid advancement into a later stage trial.