On Nov. 16, 2022, Pfizer and BioNTech announced that the companies had initiated a Phase 1 study to evaluate the safety, tolerability and immunogenicity of a next generation COVID-19 vaccine candidate that aims to enhance SARS-CoV-2 T cell responses and potentially broaden protection against COVID-19.

This candidate, BNT162b4, is composed of a T cell antigen mRNA encoding for SARS-CoV-2 non-spike proteins that are highly conserved across a broad range of SARS-CoV-2 variants and will be evaluated in combination with the companiesﾒ Omicron BA.4/BA.5-adapted bivalent COVID-19 vaccine.

The vaccine candidate was evaluated in a U.S.-based study (NCT05541861) enrolling approximately 180 healthy individuals between 18 and 55 years of age, who had received at least three doses of an mRNA-based COVID-19 vaccine.