The company is producing the seed stock using its BioComo (BC)-PIV technology and is using Millipore Sigma BioRelliance Services for manufacturing. BC-PIV is a nontransmissible viral vector co-developed by BioComo and Mie University. The BC-PIV SARS-COV-2 vaccine can be developed as an intranasal vaccine in addition to an intramuscular injection because of its high affinity to nasal and upper respiratory tract mucosa, where it is expected to induce local mucosal immunity.

The vector is derived from recombinant human parainfluenza virus type 2 (hPIV2). It is a highly efficient system that can transfer multiple foreign proteins and is designed to display not only the gene but also foreign large proteins on the surface and inside of the viral membrane. BC-PIV elicits good immunogenicity against antigen proteins without adjuvants.

Master virus seed stock is necessary to produce the BC-PIV SARS-CoV-2 vaccine. By infecting stock to the packaging cells, the BC-PIV/SARS-CoV-2 product is produced, which is recovered and purified to produce the vaccine product for clinical trials.