VXA-CoV2-1

The Phase I open-label study analysed the safety and immunogenicity of the Covid-19 vaccine candidate. Credit: PIRO4D / Pixabay. Vaxart has reported the latest data from the Phase I trial of its first Covid-19 oral vaccine construct, VXA-CoV2-1, which showed broad cross-reactivity against other coronaviruses. The open-label study analysed the safety and immunogenicity of the vaccine candidate. According to the trial data, the oral Covid-19 vaccine-induced substantial CD8+ T-cell responses, as measured by IFN-g and TNF-a induction. Vaxart also carried out a comparative experiment in which this study data was compared to T-cell responses from people who were vaccinated with the Moderna or Pfizer’s mRNA vaccine for Covid-19. It was observed that the mRNA vaccines induced limited T-cell responses. Vaxart CEO Andrei Floroiu said: “Data obtained from the Phase I study were compared to data from volunteers subsequently vaccinated with the Moderna or Pfizer mRNA vaccine distributed under emergency use authorisations (EUAs) and suggest that the same may be true against coronavirus. “Our vaccine’s immune response appears very different than that seen from the leading injectables, mucosal antibodies rather than serum antibodies and more potent T-cell responses.” Data showed that Vaxart’s vaccine candidate included greater CD8+ T-cell responses versus the Pfizer and Moderna vaccines. It stimulated a T cell response against SARS-Cov-2 and also demonstrated cross-reactivity against various endemic coronaviruses, including 229E, NL63, HKU1 and OC43. Furthermore, N protein responses to SARS-CoV-1 were observed to last 17 years on infection and cross-react to SARS-CoV-2. The vaccine candidate also elicited specific IgA antibodies in the mucosa. These mucosal responses demonstrated that they are cross-reactive against other coronaviruses, including SARS-CoV-1, MERS and the endemic common cold viruses 229E, NL63, HKU1, and OC43. Vaxart chief scientific officer Dr Sean Tucker said: “CD8+ T-cells produced by our vaccine can recognise and are capable of destroying cells infected with the virus, including in the mucosa. “The strength of T-cell responses against both S and N proteins, which we targeted, leads us to believe that VXA-CoV2-1 offers a promising solution to variants.” In February, Vaxart reported preliminary data from its Phase I study that showed VXA-CoV2-1 triggered multiple immune responses against SARS-CoV-2 antigens.

Vaxart oral vaccine induced higher CD8+ T-Cell responses than those seen with Moderna or Pfizer vaccines in comparative experiment conducted by the Company IgA antibodies triggered in the mucosa, show broad cross-reactivity SOUTH SAN FRANCISCO, Calif., May 03, 2021 (GLOBE NEWSWIRE) -- Vaxart, Inc. (Nasdaq: VXRT), a clinical-stage biotechnology company developing oral recombinant vaccines that are administered by tablet rather than by injection, announced today at Vaxart’s key opinion leader event that new data obtained from its Phase I COVID-19 trial added to the evidence suggesting that VXA-CoV2-1, the company’s first COVID-19 oral vaccine construct that triggers mucosal immunity and includes both the S and the N SARS-Cov-2 proteins, has broad cross-coronavirus activity. “We have previously announced study data showing that our oral vaccine could be as protective as the leading injectable against flu, and that it does so by triggering a very different immune response. Data obtained from the Phase I study were compared to data from volunteers subsequently vaccinated with the Moderna or Pfizer mRNA vaccine distributed under emergency use authorizations (EUAs) and suggest that the same may be true against coronavirus. Our vaccine’s immune response appears very different that that seen from the leading injectables: mucosal antibodies rather than serum antibodies, and more potent T-cell responses,” said Andrei Floroiu, Vaxart’s chief executive officer. “For our first oral COVID-19 vaccine candidate, we believe that these differences in immunogenicity profile may have a benefit in cross-reactive protection.” The Phase I open-label study is intended to evaluate the safety and immunogenicity of Vaxart’s vaccine candidate. Data obtained from Vaxart’s oral COVID-19 vaccine Phase I trial showed substantial CD8+ T-cell responses, as measured by IFN-g and TNF-a induction. In a comparative experiment conducted by Vaxart, Phase I study data was compared to T-cell responses from volunteers subsequently vaccinated with the Moderna or Pfizer mRNA vaccine, indicating the mRNA vaccines induced fewer T-cell responses. “We measured the T-cell responses in 9 volunteers vaccinated with the mRNA vaccines under EUAs and compared them in the same assays at the same timepoints to T-cell responses induced in subjects participating in our clinical trial (N=26 paired samples, or N=7 in the sub-study). Our vaccine appeared to produce CD8+ T-cell responses of a higher magnitude,” said Dr. Sean Tucker, chief scientific officer at Vaxart. “CD8+ T-cells produced by our vaccine can recognize and are capable of destroying cells infected with the virus, including in the mucosa. If you are effective at killing the virus-infected cells in the upper respiratory tract, you may be more likely to recover quicker or have a very mild course of infection,” he said. “The strength of T-cell responses against both S and N proteins, which we targeted, leads us to believe that VXA-CoV2-1 offers a promising solution to variants.” In his presentation, Dr. Tucker discussed: About Vaxart Vaxart is a clinical-stage biotechnology company developing a range of oral recombinant vaccines based on its proprietary delivery platform. Vaxart vaccines are designed to be administered using tablets that can be stored and shipped without refrigeration and eliminate the risk of needle-stick injury. Vaxart believes that its proprietary tablet vaccine delivery platform is suitable to deliver recombinant vaccines, positioning the company to develop oral versions of currently marketed vaccines and to design recombinant vaccines for new indications. Its development programs currently include tablet vaccines designed to protect against coronavirus, norovirus, seasonal influenza, and respiratory syncytial virus (RSV), as well as a therapeutic vaccine for human papillomavirus (HPV), Vaxart’s first immuno-oncology indication. Vaxart has filed broad domestic and international patents covering its proprietary technology and creations for oral vaccination using adenovirus and TLR3 agonists. Note Regarding Forward-Looking Statements This press release contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, included in this press release regarding Vaxart’s strategy, prospects, plans, and objectives, results from pre-clinical and clinical trials, commercialization agreements and licenses, beliefs and expectations of management are forward-looking statements. These forward-looking statements may be accompanied by such words as “should,” “believe,” “could,” “potential,” “will,” “expected,” “plan,” and other words and terms of similar meaning. Examples of such statements include, but are not limited to, statements relating to Vaxart’s ability to develop and commercialize its product candidates and clinical results and trial data (including plans with respect to the COVID-19 vaccine product candidates); expectations relating to Vaxart’s relationship with Emergent BioSolutions, Inc., Kindred Biosciences and Attwill Medical Solutions Sterilflow, LP, including their ability to produce cGMP vaccines and the timing thereof; Vaxart’s expectations with respect to the important advantages it believes its oral vaccine platform can offer over injectable alternatives, particularly for coronaviruses such as SARS, MERS and SARS-CoV-2; expectations regarding Vaxart’s ability to develop effective vaccines against new and emerging variant strains; expectations regarding the timing and nature of future developments and announcements, including those related to trials and studies; the potential applicability of results seen in our preclinical studies or trials to those that may be seen in humans or clinical trials; the expected role of mucosal immunity in blocking transmission of COVID-19; and Vaxart’s expectations with respect to the effectiveness of its product candidates, including Vaxart’s potential role in mitigating the impact of COVID-19. Vaxart may not actually achieve the plans, carry out the intentions or meet the expectations or projections disclosed in the forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions, expectations, and projections disclosed in the forward-looking statements. Various important factors could cause actual results or events to differ materially from the forward-looking statements that Vaxart makes, including uncertainties inherent in research and development, including the ability to meet anticipated clinical endpoints, commencement and/or completion dates for clinical , regulatory submission dates, regulatory approval dates and/or launch dates, as well as the possibility of unfavorable new clinical data and further analyses of existing clinical data; the risk that clinical trial data are subject to differing interpretations and assessments by regulatory authorities; whether regulatory authorities will be satisfied with the design of and results from the clinical studies; decisions by regulatory authorities impacting labeling, manufacturing processes, and safety that could affect the availability or commercial potential of any product candidate, including the possibility that Vaxart’s product candidates may not be approved by the FDA or non-U.S. regulatory authorities; that, even if approved by the FDA or non-U.S. regulatory authorities, Vaxart’s product candidates may not achieve broad market acceptance; that a Vaxart collaborator may not attain development and commercial milestones; that Vaxart or its partners may experience manufacturing issues and delays due to events within, or outside of, Vaxart’s or its partners’ control, including the recent outbreak of COVID-19; difficulties in production, particularly in scaling up initial production, including difficulties with production costs and yields, quality control, including stability of the product candidate and quality assurance testing, shortages of qualified personnel or key raw materials, and compliance with strictly enforced federal, state, and foreign regulations; that Vaxart may not be able to obtain, maintain and enforce necessary patent and other intellectual property protection; that Vaxart’s capital resources may be inadequate; Vaxart’s ability to resolve pending legal matters; Vaxart’s ability to obtain sufficient capital to fund its operations on terms acceptable to Vaxart, if at all; the impact of government healthcare proposals and policies; competitive factors; and other risks described in the “Risk Factors” sections of Vaxart’s Quarterly and Annual Reports filed with the SEC. Vaxart does not assume any obligation to update any forward-looking statements, except as required by law.