Due to cost, availability, and published efficacy data of another vaccine design, RaDVaC has discontinued its use of its original chitosan and peptide vaccine platform, and has replaced it with the “Prime and Spike” approach published by Mao and colleagues.
From the beginning of the SARS-CoV-2 pandemic the Rapid Deployment Vaccine Collaborative (RaDVaC) has designed, refined, self-produced and self-administered multiple generations of chitosan and peptide nasal vaccine formulations. However, many people reported difficulty in having the peptides synthesized. Plus, although the per dose cost of the peptides was low if ordered at large scale, small-scale production was expensive, and overall production costs were minimally $1000, and typically more. And for various reasons, it was also challenging to assess efficacy.
To support more rapid deployment and widespread adoption, RaDVaC has adopted the vaccine platform published by Mao and colleagues of the Iwasaki lab at Yale. Their extremely simple, off-the-shelf vaccine design consists of a single component—a SARS-CoV-2 Spike protein trimer—and no adjuvant. They showed that the vaccine elicits robust T-cell and B-cell immune responses. RaDVaC has experimented with this vaccine and because it consists of a single, relatively inexpensive and commercially available ingredient, we have adopted it as our default nasal vaccine. We currently use it in combination with commercial injectable vaccines in a standard prime and spike approach: the injected vaccine is followed a few weeks later by self-administration of the nasal vaccine.