April 8, 2021 -- ImmunityBio has reported initial data from a phase I trial suggesting its COVID-19 vaccine candidate stimulates the generation of T cells reactive to the spike (S) and nucleocapsid (N) protein antigens delivered by the vaccine.
The vaccine was delivered to healthy volunteers via a single subcutaneous injection. Between 14 and 16 days after the dose, the mean level of patients' T cells generated in response to the company's hAd5 S+N T-cell vaccine was 10 times higher for N-specific T cells. By day 21, both S and N T-cell responses had achieved levels 10 times higher than prevaccination levels.
The mean T-cell levels seen in the vaccinated participants were equivalent to those for patients recovered from infection by the SARS-CoV-2 virus, the company reported.
Previously, ImmunityBio reported that T cells isolated from previously infected individuals react to the antigens delivered by the vaccine, indicating that immune responses to the vaccine could be protective against SARS-CoV-2 infection and COVID-19 illness.