Preclinical evaluation of a SARS-CoV-2 mRNA vaccine PTX-COVID19-B
Open accessPublished version of a preprint
Abstract
Abstract Safe and effective vaccines are needed to end the COVID-19 pandemic caused by SARS-CoV-2. Here we report the preclinical development of a lipid nanoparticle (LNP) formulated SARS-CoV-2 mRNA vaccine, PTX-COVID19-B. PTX-COVID19-B was chosen among three candidates after the initial mouse vaccination results showed that it elicited the strongest neutralizing antibody response against SARS-CoV-2. Further tests in mice and hamsters indicated that PTX-COVID19-B induced robust humoral and cellular immune responses and completely protected the vaccinated animals from SARS-CoV-2 infection in the lung. Studies in hamsters also showed that PTX-COVID19-B protected the upper respiratory tract from SARS-CoV-2 infection. Mouse immune sera elicited by PTX-COVID19-B vaccination were able to neutralize SARS-CoV-2 variants of concern (VOCs), including the B.1.1.7, B.1.351 and P.1 lineages. No adverse effects were induced by PTX-COVID19-B in both mice and hamsters. These preclinical results indicate that PTX-COVID19-B is safe and effective. Based on these results, PTX-COVID19-B was authorized by Health Canada to enter clinical trials in December 2020 with a phase 1 clinical trial ongoing ( ClinicalTrials.gov number: NCT04765436 ). One Sentence Summary PTX-COVID19-B is a SARS-CoV-2 mRNA vaccine that is highly immunogenic, safe, and effective in preventing SARS-CoV-2 infection in mice and hamsters and is currently being evaluated in human clinical trials.
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References 93 · Cited by 56
- Authors
- Liu, J., Budylowski, P., Samson, R., Griffin, B. D., Babuadze, G., Rathod, B., Colwill, K., Abioye, J. A., Schwartz, J. A., Law, R., Yip, L., Ahn, S. K., Chau, S., Naghibosadat, M., Arita, Y., Hu, Q., Yue, F. Y., Banerjee, A., Hardy, W. R., Mossman, K., Mubareka, S., Kozak, R. A., Pollanen, M. S., Martin Orozco, N., Gingras, A.-C., Marcusson, E. G., & Ostrowski, M. A.
- Affiliations
- University of Toronto (CA)
- Mount Sinai Hospital (CA)
- Sunnybrook Hospital (CA)
- Sunnybrook Research Institute, Toronto, ON, Canada.
- Providence Therapeutics Holdings Inc., Calgary, AB, Canada.
- University of Waterloo (CA)
- McMaster University (CA)
- St. Michael's Hospital (CA)
- Corresponding author
- Liu, Jun
- Budylowski, Patrick
- Samson, Reuben
- Marcusson, Eric G.
- Ostrowski, Mario A.
- ORCID
- Liu, Jun
- Samson, Reuben
- Griffin, Bryan D.
- Rathod, Bhavisha
- Colwill, Karen
- Abioye, Jumai A.
- Schwartz, Jordan A.
- Law, Ryan
- Yip, Lily
- Ahn, Sang Kyun
- Chau, Serena
- Arita, Yuko
- Hu, Queenie
- Yue, Feng Yun
- Banerjee, Arinjay
- Hardy, W. Rod
- Mossman, Karen
- Mubareka, Samira
- Kozak, Robert A.
- Pollanen, Michael S.
- Gingras, Anne-Claude
- Marcusson, Eric G.
- Ostrowski, Mario A.
- Venue
- Science Advances
- Published
- 2022-01-21
- Volume
- 8
- Issue
- 3
- Pages
- eabj9815-eabj9815
- ISSN
- 2375-2548 (ISSN-L)
- PMC
- PMC8769538
- OpenAlex
- W4220971507
- Cited by
- 56
- References
- 93
- Citations by year
- 2026: 3 · 2025: 13 · 2024: 8 · 2023: 19 · 2022: 10 · 2021: 3
- FWCI
- 6.11
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- cc-by
- Locations
- Science Advances (publishedVersion, cc-by)
- bioRxiv (Cold Spring Harbor Laboratory) (acceptedVersion)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- HARVEST (University of Saskatchewan) (acceptedVersion, cc-by)
- Funders
- Royal Bank of Canada
- Krembil Foundation
- Canadian Institutes of Health Research (COVID-19)
- Topics
- Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
- Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 detection and testing
- Life Sciences › Agricultural and Biological Sciences › Animal Science and Zoology › Animal Virus Infections Studies
- Keywords
- SARS-CoV-2, COVID-19 vaccines, mRNA vaccines, lipid nanoparticle formulation, neutralizing antibodies, humoral and cellular immune response, vaccine safety, variants of concern, hamster challenge model, mouse vaccination
- MeSH terms
- COVID-19, SARS-CoV-2, COVID-19 Vaccines, mRNA Vaccines, Animals, Antibodies, Viral, Canada, Cell Line, Drug Evaluation, Preclinical, Female, Cricetinae, Humans, Immunity, Cellular, Liposomes, Male, Mice, Inbred BALB C, Mice, Inbred C57BL, Vaccines, Synthetic, CD8-Positive T-Lymphocytes, Th1 Cells, CD4 Lymphocyte Count, Mice, Nanoparticles, Immunity, Humoral, Antibodies, Neutralizing, HEK293 Cells, Spike Glycoprotein, Coronavirus
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