Sumary of New vaccinia-based COVID-19 vaccine candidate induces robust, durable immune responses:
- Researchers in Australia have developed a coronavirus disease 2019 (COVID-9) vaccine that induced robust and long-lived humoral and cellular immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in both young and aging mice.
- The team used the vaccinia virus-based Sementis Copenhagen Vector (SCV) to develop a vaccine encoding the SARS-CoV-2 spike glycoprotein that mediates viral attachment and entry into host cells.
- This spike protein is a primary target of host immune responses following natural SARS-CoV-2 infection or vaccination.
- Vaccinated mice rapidly developed robust spike-specific CD8 T cells and neutralizing antibody responses that significantly increased following a second dose.
- Neutralizing antibody activity was maintained for up to nine months post-vaccination, and durable immune memory was evident.
- The team – from the University of South Australia in Adelaide and Sementis Limited in Hackney – says the study data support the progression of SCV-based COVID-19 vaccine candidates towards efficacy testing in preclinical SARS-CoV-2 infectious disease challenge trials.
- The challenges faced in COVID-19 vaccine design Since the COVID-19 outbreak first began in Wuhan, China, in late December 2019, the causative agent – SARS-CoV-2 – has infected more than 222 million people and claimed the lives of more than 4.59 million.
- Fatality rates are disproportionately high in older individuals and those with co-morbidities such as diabetes, cardiovascular disease and immunosuppression.