CureVac and GSK have published preclinical data evaluating the immune responses and protective efficacy of CureVac’s first-generation vaccine candidate, CVnCoV, and the second-generation vaccine candidate, CV2CoV, against SARS-CoV-2 in non-human primates. The team studied eighteen cynomolgus macaques that were vaccinated with two doses of 12 ug of lipid nanoparticle formulated CVnCoV, CV2CoV, or sham (N = 6/group).
CV2CoV induced substantially higher binding and neutralizing antibodies, memory B cell responses, and T cell responses as compared with CVnCoV. CV2CoV also induced more potent neutralizing antibody responses against SARS-CoV-2 variants, including B.1.351 (beta), B.1.617.2 (delta), and C.37 (lambda). While CVnCoV provided partial protection against SARS-CoV-2 challenge, CV2CoV afforded robust protection with markedly lower viral loads in the upper and lower respiratory tract. Antibody responses correlated with protective efficacy.
The researchers say the optimized mRNA backbone used in this work has the potential for a multivalent or combined approach to address multiple emerging variants in one vaccine. Following the current preclinical development of CV2CoV, a Phase 1 clinical trial is expected to start in the fourth quarter of 2021.
The vaccine candidate, CV2CoV, is a non-chemically modified mRNA encoding the full-length prefusion-stabilized spike protein of the SARS-CoV-2 virus and formulated within lipid nanoparticles. CV2CoV was engineered with specifically optimized non-coding regions to enable enhanced mRNA translation for increased and prolonged protein expression compared to the first-generation mRNA backbone.
- CureVac AG, Tübingen, GermanyOptimization of Non-Coding Regions Improves Protective Efficacy of an mRNA SARS-CoV-2 Vaccine in Nonhuman Primates,
- Optimization of Non-Coding Regions Improves Protective Efficacy of an mRNA SARS-CoV-2 Vaccine in Nonhuman Primates,
Makda S. Gebre, Susanne Rauch, Nicole Roth, Jingyou Yu, Abishek Chandrashekar, Noe B. Mercado, Xuan He, Jinyan Liu, Katherine McMahan, Amanda Martinot, Tori Giffin, David Hope, Shivani Patel, Daniel Sellers, Owen Sanborn, Julia Barrett, Xiaowen Liu, Andrew C. Cole, Laurent Pessaint, Daniel Valentin, Zack Flinchbaugh, Jake Yalley-Ogunro, Jeanne Muench, Renita Brown, Anthony Cook, Elyse Teow, Hanne Andersen, Mark G. Lewis, Stefan O. Mueller, Benjamin Petsch, Dan H. Barouch,
The research has been published as a preprint and has not yet been peer-reviewed.
Also of Interest
- Interview with Ingmar Hoerr, Pioneer of mRNA Technology and Co-founder of CureVac,
As a Ph.D. student, Hoerr discovered that mRNA can be used as a therapeutic vaccine or agent when administered directly into tissues
- Collection: SARS-CoV-2 Virus
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