Vaxart, Inc. announced complete data from a Phase 1b trial of its oral norovirus vaccine candidate in older adults, showing robust and durable antibody and T-cell responses. The study demonstrated the vaccine’s ability to generate mucosal antibody responses beyond the administration site, a key factor for combating gastrointestinal viruses. The findings were published in Science Translational Medicine.
This news is important because norovirus poses a significant health risk to older adults, a demographic often less responsive to traditional injected vaccines. This oral vaccine offers a potential solution by stimulating strong immune responses, including at mucosal sites, where the virus initially infects. The safety profile, with only mild to moderate side effects, further strengthens the vaccine’s potential for this vulnerable population. Additionally, the ability of an oral vaccine to generate immune responses beyond the gut suggests broader applicability of Vaxart’s platform for other diseases.
The Phase 1b trial involved two age groups (55-65 and 66-80) receiving three different dose levels of the oral vaccine or a placebo. Significant increases in serum anti-VP1 IgA and IgG antibodies were observed, with no significant differences between the age groups. Importantly, the vaccine induced mucosal-homing antibody-secreting B cells and T cells, contributing to potentially longer-lasting protection. Notably, the oral administration triggered robust IgA responses in saliva and the nasal cavity, demonstrating the potential for broader mucosal immunity.
This positive data reinforces the potential of Vaxart’s oral vaccine platform. It paves the way for continued development, with a planned Phase 1 trial comparing second-generation norovirus vaccine constructs to the first-generation version in the near future. This advancement could significantly impact norovirus prevention in older adults and further validate the platform’s potential for other vaccine candidates.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
