Developing a liquid formulation for CVXGA1 COVID-19 intranasal vaccine

Developing a liquid formulation for CVXGA1 COVID-19 intranasal vaccine ABSTRACT In this Phase I SBIR application, we propose to develop a liquid formulation for CVXGA1 COVID-19 intranasal vaccine. The ongoing global coronavirus disease 2019 (COVID-19) pandemic has resulted in the loss of many lives and social economic disruptions. Variants with higher transmission rates and ability to evade vaccine or natural infection elicited host immune responses have continuously emerged leading to breakthrough infections despite additional booster doses. The next generation of COVID-19 vaccine, that is also accessible to the developing countries, is needed to stop SARS-COV-2 transmission. Parainfluenza virus type 5 (PIV5) is an excellent viral vector for expressing foreign antigens to fight many viral and bacterial pathogens. A single intranasal immunization with CVXGA1 (PIV5 expressing SARS-CoV-2 S protein) induces mucosal, humoral, and cellular immune responses, providing protection against SARS-CoV-2 challenge in mice, hamsters, ferrets, cats, and Africa green monkeys. CVXGA1 also blocked contact transmission. CVXGA1 vaccine is currently in phase 1 clinical studies (NCT04954287). The current CVXGA1 vaccine is formulated in sucrose phosphate glutamine (SPG) buffer which is stable at -80 oC and -20 oC but not stable at 4 oC. The 4 oC stable liquid formulation is critical to the launch of this intranasal vaccine for global immunization. We propose to identify a formulation which can provide CVXGA1 stability at 4 oC for a minimum of 4 months. We propose to first optimize the pH for CVXGA1 storage, then screen multiple excipients to select at least two lead formulations for further characterization, including immunogenicity studies. The Phase II SBIR proposal will focus on long-term storage of CVXGA1 in the chosen dose device (such as prefilled sprayer) and vaccine evaluation after storage.