Subject terms
B-cell deficiency, granuloma, CoVac-1-related adverse, SARS-CoV-2-specific T-cell, T-cell
SECONDARY, GRANULOMA
T-cell immunity is central for control of COVID-19, particularly in patients incapable of mounting antibody responses. CoVac-1 is a peptide-based T-cell activator composed of SARS-CoV-2 epitopes with documented favorable safety profile and efficacy in terms of SARS-CoV-2-specific T-cell response. We here report a Phase I/II open-label trial (NCT04954469) in 54 patients with congenital or acquired B-cell deficiency receiving one subcutaneous CoVac-1 dose. Immunogenicity in terms of CoVac-1-induced T-cell responses and safety are the primary and secondary endpoints, respectively. No serious or grade 4 CoVac-1-related adverse events have been observed. Expected local granuloma formation has been observed in 94% of study subjects, whereas systemic reactogenicity has been mild or absent. SARS-CoV-2-specific T-cell responses have been induced in 86% of patients and are directed to multiple CoVac-1 peptides, not affected by any current Omicron variants and mediated by multifunctional T-helper 1 CD4Here, Heitmann et al. report results from a Phase I/II trial evaluating CoVac-1, a peptide-based T-cell activator, in patients with B-cell deficiency, demonstrating potent induction of SARS-CoV-2-specific T-cell responses along with a favorable safety profile.