Sequence analysis suggests that Gritstone’s TCEs are minimally impacted by Omicron. Specifically, of the 146 non-Spike TCE delivered within Gritstone's vaccine currently in clinical trials in the UK and US, only 3 (~2%) are impacted by Omicron. Similar minimal impact of Omicron is observed in two new vaccine TCE constructs expected to enter clinical trials in South Africa before year end.
“Our value proposition in immunotherapy has always centered around two core pillars – cutting-edge TCE identification and delivering potent vaccines that can elicit strong, broad, and durable immune responses,” said Andrew Allen, MD, PhD, Gritstone’s Chief Executive Officer. “Strong neutralizing antibody responses to Spike-based vaccines have been shown to be highly protective against COVID-19. However, the possibility of substantial viral resistance arising from Spike mutations has always been present, and Omicron may represent the embodiment of this threat. While engineering an Omicron form of Spike is achievable, it is clearly ideal to both address novel Spike variants and also reduce the likelihood of further variants arising, by delivering a coordinated immune attack against both Spike and other more conserved SARS-CoV-2 genes. This is the path Gritstone has followed to date.
