The Vaxart technology is based on the potential to prevent or inhibit infectious diseases by using orally-delivered vaccines by tablets, eliminating intramuscular injection concerns which may involve pain, fear of needles, cross-contamination, dosing inconsistencies, and higher cost for large-scale immunizations.^[5][6] As a proof of concept for oral vaccination efficacy, an oral vaccine against polio was proved to be safe and effective, and is in common use in many countries.^[7][8][9]

Vaxart uses enteric-coated tablets to protect the active vaccine from acidic degradation in the stomach, delivering the vaccine into the small intestine where it can engage the immune system to stimulate systemic and mucosal immune responses against a virus.^{[10][11][6][12]}

Vaxart uses a specific virus called adenovirus type 5 (Ad5) as a delivery biological "vector" to carry genes coding for the antigen to generate a protective immune response.^[13][6][12] The Ad5 vector delivers the antigen to the epithelial cells lining the mucosa of the small intestine where it stimulates the immune system to respond against the vaccine antigen, creating a systemic immune response against a virus.^[11][6][12]

In addition to its focus on infectious diseases, Vaxart has expanded its vaccine development efforts to include therapeutic vaccines for chronic viral infections and cancer. These efforts are anchored in the company's innovative technology that enables the creation of tablet-based vaccines, which can generate broad and durable immune responses, including systemic, mucosal, and T-cell responses. This comprehensive immune activation is particularly critical in the context of chronic viral infections and cancer, where both systemic and localized immune responses play a pivotal role in effective treatment.^[14]

Influenza Vaccine edit

The lead vaccine candidate by Vaxart is an influenza oral tablet vaccine, which showed safety and neutralizing antibody responses to influenza virus in a 2015 Phase I clinical trial.^[15] A 2016-17 Phase II trial of the Vaxart oral flu vaccine, VXA-A1.1, showed that the vaccine was well-tolerated and provided immunity against virus shedding, outperforming the effectiveness of an established intramuscular vaccine.^[16] In 2018, Vaxart completed a Phase II challenge study, in which the Vaxart influenza tablet vaccine demonstrated a 39 percent reduction in clinical disease relative to placebo, compared to a 27 percent reduction by the injectable flu vaccine, Fluzone.^[11]

COVID-19 vaccine edit

In January 2020, Vaxart announced development of a tablet vaccine to inhibit COVID-19. Some of its competitors were companies such as Novavax, Inovio Pharmaceuticals, and Moderna.^{[17][13][18][11]}

In February 2020, Vaxart began a program to develop an oral tablet vaccine for COVID-19.^[17][13][18]

In April, the company reported positive immune responses in laboratory animals from its tests with a vaccine candidate for COVID-19.^[19]

In January 2024, Vaxart received a grant from the United States Biomedical Advanced Research and Development Authority (BARDA). The grant, amounting to $9.27 million, is allocated for the preparation of a large-scale Phase 2b clinical trial involving 10,000 participants. This trial is designed to evaluate the efficacy of Vaxart's innovative oral pill XBB COVID-19 vaccine candidate in comparison to an approved mRNA vaccine. The funding is part of Project NextGen, a substantial $5 billion initiative by the U.S. Department of Health and Human Services (HHS) focusing on the development of new, innovative vaccines and therapeutics that provide broader and more durable protection against COVID-19. The oral vaccine platform developed by Vaxart is noted for its potential advantages, including generating mucosal immunity and offering a cross-reactive response to various COVID-19 variants. ^[20]

Norovirus vaccine edit

Vaxart has been progressing in the development of an oral tablet vaccine for Norovirus, the leading cause of acute gastroenteritis globally. Norovirus significantly impacts all age groups, particularly young children and the elderly, causing millions of cases annually with substantial healthcare and economic burdens.

Its vaccine candidate is a bivalent oral tablet targeting major norovirus genogroups GI and GII. The tablet form is specifically crafted to generate antibodies in the intestine, the primary site of norovirus infection.

In December 2022, Vaxart received significant funding and support from the Bill & Melinda Gates Foundationfor a study focusing on breastfeeding mothers and their infants. This study aligns with Vaxart’s broader norovirus vaccine program goals, targeting critical and at-risk populations globally.^[21]

In 2023, Vaxart initiated a Phase 1 trial (VXA-NVV-108) focused on lactating mothers, aiming to evaluate the vaccine's ability to induce breast milk antibodies and their transfer to infants.^[22] Furthermore, in July 2023, Vaxart announced positive topline data from a dose-ranging Phase 2 clinical trial of its bivalent norovirus vaccine candidate. The study met all primary endpoints, showing the vaccine was well-tolerated with robust immunogenicity. ^[23]

Additionally, in September 2023, Vaxart announced top-line data from its Phase 2 challenge study of the monovalent norovirus vaccine candidate. ^[24] This study met 5 of its 6 primary endpoints, demonstrating a statistically significant reduction in norovirus infection rate and a substantial reduction in viral shedding, while maintaining a well-tolerated safety profile.

In 2019, several hedge funds invested in Vaxart, with the largest investment coming from Armistice Capital which acquired 25.2 million shares.^[25][26]

• Coronavirus disease 2019
• COVID-19 pandemic
• Severe acute respiratory syndrome–related coronavirus
• Vaccine
• Respiratory disease
• 2009 flu pandemic vaccine