Layer-by-Layer Delivery of Multiple Antigens as a SARS-CoV-2 Vaccine

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019-2020 has caused a global pandemic, and no preventative measures that are demonstrated broadly effective and safely available. Various platforms for vaccine development are available, including virus vectored vaccines, protein subunit vaccines, genetic vaccines, and monoclonal antibodies for passive immunization. Each of these categories have candidates that are under evaluation for SARS-CoV-2, with each having discrete benefits and deficiencies. Inactivated and live-attenuated virus-based vaccines are vaccine types developed using the most traditional approaches. Although they generally induce highly potent immune responses and/or protection, the possibility for incomplete inactivation of viruses or recovering virulence exists, resulting in significant safety concerns. Therefore, the development of a safe and effective vaccine is critically required in response to the global health crisis known as COVID-19. Instead, subunit vaccine maintains much stronger safety profile; however, the immunogenicity of these vaccines is usually lower than that of virus- or viral vector-based vaccines, often requiring optimization of components, inclusion of appropriate adjuvant. To overcome anticipated challenges with SARS-CoV-2 vaccines, Luna proposes to develop a safe, chitosan-based nanoparticle delivery formulation for antigen delivery. Luna’s LbL-CoV19, a proprietary nano-vaccine technology, would enhance the immunogenicity of the immunogen and stimulate effective complementary immune responses.