A Phase-I Study of a Nanoparticle-based Peptide Vaccine Against SARS-CoV-2

This trial is Stage 2 of a 2-part adaptive trial. The study aims to investigate the safety of 2 doses of a T-cell priming specific cocktail of Coronaviruses peptides mounted on a gold nanoparticle. Note: Stage 1 of the 2-part adaptive trial, testing a specifically selected mix of Dengue virus peptides, commenced Aug 2021. This is now in follow up (NCT04935801).

Despite drastic quarantine measures, SARS-CoV-2 continues to propagate and threaten global economies and healthcare systems. There is universal consensus on the need for vaccination to protect against complications, reduce viral shedding and therefore prevent severe manifestation of disease and reduce hospitalisations. Coronavirus harbours the potential to become a seasonal disease. It is moving towards being a ''new flu'' with potential perennial circulation and continuously evolving Variants of Concern (VOCs), needing diverse vaccines to control it. The Global Vaccine Alliance, GAVI, has specifically advocated for vaccine diversity as a means to ensure equality and access as well as a means of maximising scalability. Nanoparticle antigen delivery systems have been developed to enrich specific targeting of immune receptors. These carrier systems are designed to facilitate antigen uptake and processing by antigen presenting cells (APCs), as well as to control antigen release and protect them from premature proteolytic degradation. This more targeted response also allows to reduce the effective antigen dose (to nanomoles) and mimic a replicating infection with zero risk of developing the infectious disease. The hypotheses are listed below: 1. The scale of the COVID-19 pandemic requires multiple vaccine candidates to ensure democratic and rapid access to protection by: * Providing a range of vaccine choices tailored to variations in immunological profiles across demographics as well as suited to environments with various levels of resources (cold chain etc). * Distributing and parallelizing manufacture, to speed up scale, avoid reagent stock limitations and dilute monopolies. 2. The ability for SARS-CoV-2 to mutate, requires multiple vaccine candidates to ensure robust and sustainable protection. Vaccines with a range of epitopes and immune targets provide immunological diversity and reduce vulnerability to mutant escape. 3. Nanotechnology fulfils the needs of a COVID vaccine by being a rapidly scalable and modular platform. 4. Humoral immunity may be transient and insufficient against emerging variants of SARS-CoV-2. 5. Cellular immunity against SARS-CoV-2 is lasting and associated with recovery in COVID-19. The proposed vaccine of this trial specifically seeks to diversify the immunological target response by carefully curating an MHC-I binding antigen cocktail from the SARS viruses ligandome and loading it onto a robust nanoparticle for controlled release and coupled T-cell immunostimulation. It also specifically seeks to avoid generating a humoral response, which has the potential to be transient and even detrimental in certain cases. For this second stage of the trial, the objectives are are follows: Primary: To evaluate the safety and reactogenicity of two intradermal injections of two different doses of the investigational COVID peptide T-cell inducing vaccine (PepGNP-Covid19) administered to healthy volunteers in Switzerland as a: 1. candidate vaccine for the prevention of COVID-19 2. proof-of-concept for a rapidly scalable modular peptide vaccine platform. Secondary: 1. To assess the evidence of a CD8 T-cell mediated immune response as a surrogate of protection against severe COVID-19 disease using a novel peptide set-point vaccine in healthy adults. 2. To assess the presence of an antibody mediated response. For naNO-COVID, a total of 26 eligible participants will be randomised into the following groups: Group 1 (n=13) 10 low dose (LD) PepGNP-Covid19 (2.5nmol peptide +12.8ug) + 3 Comparator. Group 2 (n=13) 10 high dose (HD) PepGNP-Covid19 (7.5nmol + 38.3ug) + 3 Comparator. Thus, 20/26 vaccine and 6/26 Comparator controls. Allocations of vaccine vs bpC for each group are double-blinded. Each arm will be staggered into a ''Pioneer'' group (3/13 participants) followed a week later after a safety review by the remaining 10/13 ''Followers''. This is the second stage of a 2-stage study investigating the safety of 2 vaccines from a T-cell priming vaccine platform for emerging diseases. (stage 1 = naNO-Dengue, stage 2 = naNO-COVID).