All RaDVaC staff received our commercial vaccine doses as soon as we were eligible. We believe it is wise for all approved individuals to consider commercial vaccination. As an experimental platform, the RaDVaC vaccine approach continues to be an important complement to the established vaccine development pipeline and commercial vaccine designs.
RaDVaC retires use of chitosan-peptide vaccine formulations and adopts Prime and Spike
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, and we have provided detailed descriptions of the design and production in a series of white papers (all of which can be accessed below). 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 expensive (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. Ideally, 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.
Key features of the RaDVaC chitosan and peptide anti-SARS-CoV-2 vaccine (retired)
- Intranasally delivered. Very simple to self administer. No injection, no needles.
- Synthetic peptide epitopes / antigens. These peptides are small synthetically produced portions of viral sequences. A peptide-based vaccine is not infectious. We have selected these peptides as the basis for our vaccine against SARS-CoV-2. The antigen portion of the vaccine can be substituted by other antigens; for example, recombinant SARS-CoV-2 Spike RBD. By appropriate selection of antigens, the intranasal vaccine design described here can also be adapted for use against other viruses, especially respiratory viruses, such as influenza or non-SARS coronaviruses.
- Chitosan nanoparticle delivery. Chitosan is a form of chitin, which is found in mushrooms and the shells of crustaceans such as shrimp and crabs (seafood allergies are not allergies to chitin). Chitosan acts as both delivery vehicle and immunostimulatory adjuvant.
- Extremely simple and inexpensive preparation with easily obtained materials.
- Short-term safety. This type of vaccine has shown excellent safety in animal studies and human clinical trials. The RaDVaC vaccine has been used repeatedly over several months, by over 100 self-experimenters, with the most extreme complication in some recipients of stuffy noses.
Protocols for the simple and robust production of chitosan nanoparticle vaccines for intranasal delivery have been published for over two decades. Intranasal delivery of chitosan-based vaccines have shown mild side effects and high levels of efficacy of both mucosal and systemic immunity, when delivered in a prime-boost regimen (in both animal models and human trials).
Click here to see a list of essential Materials and equipment
Click here for access to our White Paper, which contains all relevant scientific details, methods and protocols