Vaxart Announces Positive Hamster Challenge Study Data for its Oral COVID-19 Vaccine

Vaccinated Hamsters Show Protection from COVID-19 based on Prespecified Indicators of Clinical Outcomes

SOUTH SAN FRANCISCO, Calif., Oct. 14, 2020 (GLOBE NEWSWIRE) -- Vaxart, Inc., (NASDAQ: VXRT), a clinical-stage biotechnology company developing oral vaccines that are administered by tablet rather than by injection, announced today the topline results from its Hamster Challenge Study. The available results show that all hamsters that received two oral doses of COVID-19 vaccine candidate showed no systemic weight loss, a key indicator of protection against COVID-19 in this animal model.

“Our oral vaccine showed that 100% of hamsters receiving two oral doses of vaccine in the study were protected against systemic weight loss, as well as lung weight gain, which is a key indicator of lung damage due to infection,” said Sean Tucker, Ph.D., chief scientific officer, and founder of Vaxart. “Given that the hamster is a great model for assessing severe infection, this study helps to validate our vaccine’s potential to provide potent protection against COVID-19. These results increase our confidence as we move our vaccine candidate into human clinical trials.”

The study evaluated Vaxart’s recombinant adenoviral vaccine, with doses given at 0 and 4 weeks. Animals were challenged with SARS-CoV-2 at week 8. Topline data demonstrated that all unvaccinated animals lost at least 8% of their body weight, and all showed evidence of lung disease as measured by relative weight gain in the lungs. By contrast, all animals vaccinated with two doses of the oral vaccine maintained or gained body weight by the end of the experiment, a statistically significant result (p<0.001). Additionally, these animals were protected against the lung weight gain seen in the unvaccinated animals (p<0.001). For unvaccinated animals, lung weight as a percentage of body weight was approximately twice that of the animals that received two oral doses of the vaccine. The experiment was designed to monitor systemic weight for 5 days before animals were assessed for lung disease. N=8 per group. Hamsters receiving one oral dose had partial protection. Full results from the study will be published when data analysis is complete.