Abstract
An effective vaccine is needed to halt the spread of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic. Recently, we reported safety, tolerability and antibody response data from an ongoing placebo-controlled, observer-blinded phase I/II coronavirus disease 2019 (COVID-19) vaccine trial with BNT162b1, a lipid nanoparticle-formulated nucleoside-modified mRNA that encodes the receptor binding domain (RBD) of the SARS-CoV-2 spike protein1. Here we present antibody and T cell responses after vaccination with BNT162b1 from a second, non-randomized open-label phase I/II trial in healthy adults, 18–55 years of age. Two doses of 1–50 μg of BNT162b1 elicited robust CD4+ and CD8+ T cell responses and strong antibody responses, with RBD-binding IgG concentrations clearly above those seen in serum from a cohort of individuals who had recovered from COVID-19. Geometric mean titres of SARS-CoV-2 serum-neutralizing antibodies on day 43 were 0.7-fold (1-μg dose) to 3.5-fold (50-μg dose) those of the recovered individuals. Immune sera broadly neutralized pseudoviruses with diverse SARS-CoV-2 spike variants. Most participants had T helper type 1 (TH1)-skewed T cell immune responses with RBD-specific CD8+ and CD4+ T cell expansion. Interferon-γ was produced by a large fraction of RBD-specific CD8+ and CD4+ T cells. The robust RBD-specific antibody, T cell and favourable cytokine responses induced by the BNT162b1 mRNA vaccine suggest that it has the potential to protect against COVID-19 through multiple beneficial mechanisms.
【초록키워드】 COVID-19, coronavirus disease, SARS-CoV-2, Vaccine, immune response, vaccination, pandemic, Trial, Open-label, antibody, mRNA vaccine, Antibody Response, Receptor binding domain, BNT162b1, Spread, serum, Adults, Cohort, T cell, pseudovirus, RBD, sera, response, CD4+ T cells, age, mechanisms, placebo-controlled, T cell response, CD8+ T cell, CD4+ T cell, Coronavirus-2, Concentration, dose, cytokine response, geometric mean, T helper, acute respiratory syndrome, Tolerability, individual, participant, CD4+, titre, fraction, CD8+, vaccine trial, ENCODE, MOST, SARS-CoV-2 spike variants, responses, effective, RBD-binding IgG, neutralized, robust, PROTECT, produced, healthy, reported, non-randomized, individuals, elicited, nucleoside-modified mRNA, observer-blinded, the SARS-CoV-2, 【제목키워드】 COVID-19 vaccine, antibody, BNT162b1, T cell response, elicit,