Article
Author: Arriga, Roberto ; Capobianchi, Maria Rosaria ; Guidotti, Luca G ; Chiarini, Valerio ; Compagnone, Mirco ; Bucci, Federica ; Perucchini, Chiara ; Matusali, Giulia ; Giustini, Leonardo ; Roscilli, Giuseppe ; Criscuolo, Elena ; Sala, Eleonora ; Maffei, Mariano ; Wettstein, Lukas ; Palombo, Fabio ; Aurisicchio, Luigi ; Ippolito, Giuseppe ; Conti, Matteo ; Ravà, Micol ; Münch, Jan ; Mancini, Nicasio ; De Francesco, Raffaele ; Marotta, Davide ; Ciliberto, Gennaro ; Pinto, Eleonora ; Lione, Lucia ; Bono, Elisa ; Donnici, Lorena ; Paterson, Jemma ; Clementi, Nicola ; Ryan, Kathryn Ann ; Iannacone, Matteo ; Nyska, Abraham ; Ferrara, Fabiana Fosca ; Di Lucia, Pietro ; Fumagalli, Valeria ; Stoppoloni, Daniela ; D'Acunto, Emanuela ; Colavita, Francesca ; Groß, Rüdiger ; Cappelletti, Manuela ; Kuka, Mirela ; Challis, Amy-Rose ; Vitagliano, Grazia ; Muzi, Alessia ; Seidel, Alina ; Conforti, Antonella ; Castilletti, Concetta ; Pacello, Maria Lucrezia ; Marra, Emanuele ; Pavoni, Emiliano ; Caselli, Gianfranco ; Salvatori, Erika ; Rovati, Lucio ; Luberto, Laura
The COVID-19 pandemic caused by SARS-CoV-2 has made the development of safe and effective vaccines a critical priority. To date, four vaccines have been approved by European and American authorities for preventing COVID-19, but the development of additional vaccine platforms with improved supply and logistics profiles remains a pressing need. Here we report the preclinical evaluation of a novel COVID-19 vaccine candidate based on the electroporation of engineered, synthetic cDNA encoding a viral antigen in the skeletal muscle. We constructed a set of prototype DNA vaccines expressing various forms of the SARS-CoV-2 spike (S) protein and assessed their immunogenicity in animal models. Among them, COVID-eVax-a DNA plasmid encoding a secreted monomeric form of SARS-CoV-2 S protein receptor-binding domain (RBD)-induced the most potent anti-SARS-CoV-2 neutralizing antibody responses (including against the current most common variants of concern) and a robust T cell response. Upon challenge with SARS-CoV-2, immunized K18-hACE2 transgenic mice showed reduced weight loss, improved pulmonary function, and lower viral replication in the lungs and brain. COVID-eVax conferred significant protection to ferrets upon SARS-CoV-2 challenge. In summary, this study identifies COVID-eVax as an ideal COVID-19 vaccine candidate suitable for clinical development. Accordingly, a combined phase I-II trial has recently started.