A preclinical study conducted on non-human primates and published this week showed potential in a second-generation mRNA COVID-19 vaccine candidate, CV2CoV, created by the joint efforts of biopharmaceutical companies CureVac N.V. and GSK.
Among cynomolgus macaques, the new candidate — an evolution of the first-generation vaccine candidate CVnCoV — demonstrated improved immune response and protection, with solid neutralizing capacity displayed by antibodies against the virus and its variants.
“In this animal model, CV2CoV is shown to induce broad antibody and cellular immune responses very similar to the breadth of the immune responses observed after infection with SARS-CoV-2,” Dr. Igor Splawski, Chief Scientific Officer of CureVac, said. “The current study shows that the immune responses and resulting protection produced by our second-generation candidate, based on our mRNA technology featuring targeted optimizations, are substantially improved in non-human primates against both, the original SARS-CoV-2 virus as well as the Beta and Delta Variants of Concern and the Lambda Variant of Interest.”
In a challenge, CV2CoV was highly effective at clearing the virus from both the lungs and nasal passages. It also provided better activation of innate and adaptive immune responses than its forebear, leading to faster response, higher titers of antibodies, and more. All of this was based on a 12 µg dose of the candidate issued on days 0 and 28. It was tested against the Alpha, Beta, Delta, Kappa, and Lambda variants.
“The mRNA technology is a key strategic priority for us, and we are investing significantly in a number of mRNA programs focused on the collaboration with CureVac,” Dr. Rino Rappuoli, Chief Scientist and head of GSK Vaccines R&D, said. “The strong immune response and protection in pre-clinical testing of this second-generation mRNA backbone are very encouraging and represent an important milestone for its further development.”
GSK and CureVac have been working together on such technology since July 2020. Eventually, they hope to realize a multivalent or combination approach to the multiple emerging variants of COVID-19 through a single vaccine. A Phase One clinical trial is expected to start later this year.