On April 21, 2022 CureVac N.V. (Nasdaq: CVAC), a global biopharmaceutical company developing a new class of transformative medicines based on messenger ribonucleic acid ("mRNA"), reported preclinical data demonstrating immune responses and protective efficacy of a bivalent second-generation COVID-19 vaccine candidate jointly developed with GSK, combining two mRNAs encoding for the Beta and the Delta variant (Press release, GlaxoSmithKline, APR 21, 2022, View Source [SID1234612733]).
Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:
Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing
Schedule Your 30 min Free Demo!
The preclinical study, conducted in collaboration with the Friedrich-Loeffler-Institut, Germany, assessed the bivalent candidate in comparison to the corresponding monovalent candidates targeting either variant in a mouse model. Despite containing only half the dose per variant-mRNA, the combined Beta/Delta candidate elicited neutralizing antibody titers fully comparable to the monovalent candidates of the respective variant. During exposure of the vaccinated animals to either the Beta or the Delta variant, the bivalent mRNA vaccine significantly reduced the viral load in the animals. High neutralizing antibody titers were accompanied by robust T cell responses. Notably, the bivalent Beta /Delta vaccine candidate induced two-fold higher virus neutralizing antibody titers against the Omicron variant than against the Delta variant in a rat model. This finding provides evidence for a potentially increased breadth of immune responses of the bivalent approach. The full manuscript of the preclinical data is available on the preprint server bioRxiv.
"Since the beginning of the pandemic, new COVID-19 variants have continued to evolve, each characterized by different virulence and transmissibility," said Dr. Igor Splawski, Chief Scientific Officer of CureVac. "New vaccine strategies, such as multivalent approaches, combining several variant-specific mRNAs within one vaccine, can be essential to take control over the COVID-19 virus dynamic and set new standards for broadly effective vaccines against other infectious diseases. Following our recent multivalent approach for influenza, we are now taking advantage of this advanced technology approach in our COVID-19 vaccine program.
Within the study, transgenic mice expressing the human ACE2 receptor were immunized on day 0 and day 28 with a 0.5 µg dose of the monovalent second-generation vaccine candidate against either the ancestral virus (CV2CoV), the Beta (CV2CoV.351) or the Delta (CV2CoV.617.2) variant, or with a 0.5 µg dose of the bivalent vaccine candidate combining the Beta and Delta variant (CV2CoV.351+ CV2CoV.617.2). Vaccinated animals were challenged on day 56 with either the Beta or the Delta virus variant. Vaccine induced T cells, including lung-resident memory CD8+ T cells, were characterized by flow cytometry. Additionally, the neutralizing capacity of the mono- and bivalent candidates was tested against multiple virus variants, including Omicron in serum samples of immunized Wistar rats.