AKS-452

AKS-452 is a CoV-2 protein subunit vaccine candidate based on Akston’s proprietary Fc fusion protein platform. It is designed to induce a Th1/Th2 mixed immune response in patients against the Receptor Binding Domain (RBD) of the novel coronavirus spike protein. Being the primary locus for infection, the RBD is highly conserved among mutated forms of the virus.

Unlike other vaccines that must be kept refrigerated or even deep-frozen for transport and storage, AKS-452 has been shown to be shelf-stable for at least six months at 25° Celsius (77° Fahrenheit) and maintains its potency for one month at 37° Celsius (99° Fahrenheit).

This can greatly simplify distribution and is critically important for vaccinating the billions of people not served by sophisticated and costly cold-chain transportation. 

The vaccine has been engineered to use standard, low-cost, antibody manufacturing techniques, such that a single production line could be capable of producing over one billion doses per year at existing plants around the world. 

Features

  • Full Receptor Binding Domain (RBD) presented to immune system
  • Glycosylated Fc activates immune system response
  • Clinical studies show robust, neutralizing antibody production
  • Designed to induce and/or augment antibody titers in patients
  • Production uses established, high-volume methods
  • Effective at microgram doses

Development status and plans

Akston has undertaken an urgent, fast-track development and clinical evaluation of AKS-452. 

The vaccine is produced in the U.S., but designed to meet the specific needs of developing countries — low cost production and no refrigeration needed for transport or use.

The Phase I trial showed AKS-452 to be safe and well-tolerated. Most importantly, AKS-452 produced a 100% seroconversion rate in the 90 microgram single-dose regimen, as well as in the 45 microgram two dose regimen.

The ongoing Phase II clinical trial, an open-label study, is evaluating volunteers between the ages of 18 and 85 to determine safety, tolerability, and immune response. Participants will receive either one dose of 90 micrograms or two doses of 45 micrograms 28 days apart. Akston has produced the drug substance for its clinical studies in its GMP manufacturing facility in Beverly, MA. 

Disease and therapy

To prevent the spread of the SARS-CoV-2 virus and thus minimize the impact of the COVID-19 pandemic, there needs to be a sufficient level of immunity to the virus conferred to the human population. The only practical way to do this and ensure that the pandemic does not recur, is by vaccinating a very high proportion of the population, everywhere in the world, and to keep the immunity level high for an extended period of time. Akston’s AKS-452 COVID-19 vaccine provides a practical solution to the problem of vaccinating and boosting the immunity of people all over the world against the virus.

Akston’s team realized early on that its Fc-fusion protein platform could be used to design a vaccine that can be transportable at ambient temperatures, produced at very low cost, and suitable for repeated dosing if immunity wanes.