Medium-term immunogenicity of three doses of BNT162b2 and CoronaVac in Hong Kong neuromuscular disease patients.

The durability of the immunogenicity elicited by three doses of mRNA-based BNT162b2 and whole-virus inactivated CoronaVac in patients with neuromuscular diseases, particularly those on immunosuppressive drugs and variants of concern, has not been well-established. Our goal was to evaluate medium-term humoral immunogenicity outcomes after 3 doses of these vaccines. Peripheral blood samples were collected from participants 14-49 days and 155-210 days after administration of the third vaccine dose to assess humoral immune responses through serological assays.

Durability for 12 months of antibody response to a booster dose of monovalent BNT162b2 in adults who had initially received 2 doses of inactivated vaccine.

This study examined the strength and durability of antibody responses in 277 adults who received a heterologous third dose of the BNT162b2 vaccine, following two doses of an inactivated vaccine. Neutralizing antibody levels against both the ancestral virus and Omicron BA.2 subvariant decreased from one month to 6 months after the third dose, and were then maintained at 12 months.

Superior antibody and membrane protein-specific T-cell responses to CoronaVac by intradermal versus intramuscular routes in adolescents.

Background: Optimising the immunogenicity of COVID-19 vaccines to improve their protection against disease is necessary. Fractional dosing by intradermal (ID) administration has been shown to be equally immunogenic as intramuscular (IM) administration for several vaccines, but the immunogenicity of ID inactivated whole severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the full dose is unknown. This study (NCT04800133) investigated the superiority of antibody and T-cell responses of full-dose CoronaVac by ID over IM administration in adolescents.