Newcastle disease virus (NDV) expressing the spike protein of SARS-CoV-2 as vaccine candidate
Authors:Sun et al.
Key Words:Immunology, Vaccine
Pre-clinical evaluation of egg-based inactivated Newcastle disease virus (NDV) vector vaccines expressing either the SARS-CoV-2 spike protein in its wild type or a pre-fusion membrane anchored format are shown to elicit potent protection against COVID-19 vaccine in mice and hamsters
These vaccine candidates are shown to protect mice from a mouse-adapted SARS-CoV-2 challenge with no detectable viral titre and viral antigen in the lungs 11 days following a homologous prime-boost with a 3 weeks interval
In this preprint, the authors report the construction and characterization of NDV vectors expressing the SARS-CoV-2 S protein, either in its wild type (WT S) or in a pre-fusion membrane anchored format (S-F). High titres of binding and neutralizing antibodies were induced with either of three live NDV vectors. All three vectors are shown to fully protect mice from challenge with a SARS-CoV-2 mouse-adapted strain, showing no detectable viral titres and viral antigen in the lungs at day four post-challenge.
Impact for SARS-CoV2/COVID19 research efforts
Development of a vaccine for SARS-CoV2/COVID19
In vivo study (e.g. mouse, NHP)
Strengths and limitations of the paper
Novelty: First pre-clinical results of novel NDV vectored vaccines for SARS-CoV-2
Standing in the field: NDV vectored vaccines benefit from lack of prior anti-vector immunity in humans; also they can be quickly amplified in embryonated chicken eggs, which allows for high yields and low cost per dose
Appropriate statistics: No statistical analysis
Viral model used:Mouse-adapted SARS-CoV-2
Translatability:Besides its advantages regarding production NDV has also a very good safety record in humans and has been used in many oncolytic virus trials
Proof of principle mouse study, reporting the successful construction of and effective protection by novel NDV vector-based SARS-CoV-2 vaccine candidates, but without any statistical analysis or comparison to other vaccine candidates already tested in clinical trials