| Autor: |
Dominik Vahrenhorst, Rolf Fendel, Mirjam Schunk, Jacobus J. Bosch, Julian J. Gabor, Mariola Fotin-Mleczek, Thirumalaisamy P. Velavan, Thomas Verstraeten, Geert Leroux-Roels, Christoph Schindler, Olaf-Oliver Wolz, Isabel Leroux-Roels, Peter G. Kremsner, Gianluca Quintini, P. Mann, Oliver Schoenborn-Kellenberger, Andrea Kreidenweiss, Arne Kroidl, Lidia Oostvogels, Lisa Walz, Stefan Mueller |
| Rok vydání: |
2020 |
| Předmět: |
|
| Popis: |
There is an urgent need for vaccines to counter the COVID-19 pandemic due to infections with severe acute respiratory syndrome coronavirus (SARS-CoV-2). Evidence from convalescent sera and preclinical studies has identified the viral Spike (S) protein as a key antigenic target for protective immune responses. We have applied an mRNA-based technology platform, RNActive®, to develop CVnCoV which contains sequence optimized mRNA coding for a stabilized form of S protein encapsulated in lipid nanoparticles (LNP). Following demonstration of protective immune responses against SARS-CoV-2 in animal models we performed a dose-escalation phase 1 study in healthy 18-60 year-old volunteers.This interim analysis shows that two doses of CVnCoV ranging from 2 μg to 12 μg per dose, administered 28 days apart were safe. No vaccine-related serious adverse events were reported. There were dose-dependent increases in frequency and severity of solicited systemic adverse events, and to a lesser extent of local reactions, but the majority were mild or moderate and transient in duration. Immune responses when measured as IgG antibodies against S protein or its receptor-binding domain (RBD) by ELISA, and SARS-CoV-2-virus neutralizing antibodies measured by micro-neutralization, displayed dose-dependent increases. Median titers measured in these assays two weeks after the second 12 μg dose were comparable to the median titers observed in convalescent sera from COVID-19 patients. Seroconversion (defined as a 4-fold increase over baseline titer) of virus neutralizing antibodies two weeks after the second vaccination occurred in all participants who received 12 μg doses.Preliminary results in the subset of subjects who were enrolled with known SARS-CoV-2 seropositivity at baseline show that CVnCoV is also safe and well tolerated in this population, and is able to boost the pre-existing immune response even at low dose levels.Based on these results, the 12 μg dose is selected for further clinical investigation, including a phase 2b/3 study that will investigate the efficacy, safety, and immunogenicity of the candidate vaccine CVnCoV. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
