Vaxxinity is developing the world’s first multitope peptide-based vaccine against SARS-CoV-2 to make immunity to COVID-19 accessible to all.  This vaccine, UB-612, is specifically designed to allow for the inclusion and presentation of multiple epitopes (portions mimicking the SARS-CoV-2 virus) to target both B-cell (antibody) and T-cell (cellular) against SARS-CoV-2.

Of multiple SARS-CoV-2 vaccines currently in clinical development, almost all focus solely on the Spike protein. UB-612 is designed to target a critical antigen from the Spike protein, the Receptor Binding Domain (RBD), thought to be necessary for viral attachment to human cells, plus additional viral epitopes (from other viral structural proteins) designed to promote B-cell and CD8+ T-cell memory responses.

 

What makes UB-612 different?

 

Safety & tolerability

Interim Phase 1 data suggests a well tolerated vaccine with no significant safety issues observed to date.

  • No serious adverse events or adverse events
  • Minimal local/systemic adverse events after 1st and 2nd dose

.

Logistics & scalability

  • 2-8°C storage and distribution means no special cold-chain requirements, existing vaccine infrastructure could be used for distribution, even in resource-limited settings
  • Partnership with Maersk secures reliable global shipping and delivery
  • Vaxxinity, through its sister companies in the United Biomedical Group, has already scaled production to 500 million doses/year, and through both internal expansion and a network of global partnerships can increase that capacity to up to 1 billion doses/year by the end of 2021
  • 5 billion doses commercialized to date based on platform technology

“Boostability”

The Vaxxinity platform has been shown to elicit robust antibody responses in non-Covid-19 related subjects, including older adults, safely and consistently across repeat dosing over 3 years or more[1].  Antibody levels are recalled to their initial peak following each boost, regardless of the time interval since the last dose.  This will remain especially important in an environment where the field has not yet determined the durability of immunity from COVID-19 vaccines, and where we may face a seasonal recurrence of COVID-19, as we see annually with influenza.

Rapid Adaptation to Mutation

Because we make our vaccines from synthetic peptides, we can swap target epitopes and amino acid sequences with relative ease.  This means we have the potential to respond rapidly as needed to changes in the SARS-CoV-2 virus.  In fact, we successfully achieved such a response to a mutation in foot-and-mouth disease virus with our sister company’s animal health vaccine.

Design

Vaxxinity specifically designed UB-612 to allow for the inclusion and presentation of multiple epitopes to elicit both B-cell (antibody) and T-cell (cellular) responses without enhancing COVID-19 disease.  Of multiple SARS-CoV-2 vaccines currently in clinical development, almost all focus solely on the S protein.  While this is a rational target, a single protein may not raise a sufficient or broad enough immune response.  UB-612 is designed to target a critical antigen from the S protein (Receptor Binding Domain, RBD) thought to be necessary for viral attachment to human cells plus additional viral epitopes (from other viral structural proteins) designed to promote B-cell and CD8+ T-cell memory responses.

 

Preclinical Data Summary

Vaxxinity has published results of its preclinical studies here.

  • Protection shown in AAC hACE2 mice, and lack of immunopathology in lungs
  • Induces functional antibodies as well as a balanced cellular response (Th1/Th2, with Th1 polarity)
  • Neutralization of SARS-CoV-2, >100-fold higher than convalescent sera from Covid-19 patients
  • Inhibition of RBD:hACE2 interactions

The COVID-19 vaccine is currently investigational and is not yet approved or licensed in any jurisdiction for any use.

[1] Based on observations from Phase 2a Long Term Extension study of UB-311 in mild-to-moderate Alzheimer’s disease (NCT03531710)