Vaxart to Present at the 29th European Congress of Clinical Microbiology & Infectious Diseases

100% Survival Against Lethal H5N1 Avian Flu Challenge in Ferret Study

SOUTH SAN FRANCISCO, Calif.–(BUSINESS WIRE)–Vaxart, Inc. (NASDAQ: VXRT), a clinical stage biotechnology company
developing oral recombinant vaccines that are administered by tablet
rather than by injection, today announced that Roberto Mateo, Ph.D.,
lead scientist at Vaxart, will present preclinical data in a poster
presentation at the 29^th European Congress of Clinical
Microbiology and Infectious Diseases showing that Vaxart’s oral
quadrivalent influenza vaccine conferred 100% protection against a
lethal H5N1 avian influenza challenge in ferrets.

Details of the presentation are as follows:

Poster Title: Oral adenovirus-based quadrivalent influenza
vaccine protects ferrets from lethal challenge with a pandemic H5N1
influenza virus (Vietnam H5N1)
Poster Number: P0386
Date
& Time: Saturday, April 13, 2019 at 3:30 – 4:30 PM GMT
Authors:
Roberto Mateo, et al.
Session: Vaccination: from bench
to practice

The Vaxart oral quadrivalent influenza vaccine was compared head-to-head
with placebo and quadrivalent injectable Fluzone^® in ferrets
that received a lethal challenge of H5N1 avian influenza 28 days post
immunization. The Vaxart quadrivalent vaccine was matched with the
quadrivalent Fluzone, covering the same four influenza strains. Neither
the Vaxart quadrivalent vaccine nor the quadrivalent Fluzone covered
H5N1 strains. Both vaccines were administered at an equivalent dose and
animals were followed for 15 days after challenge. Ferrets in the
placebo group had a 25% survival rate while 62% of the animals in the
Fluzone group survived. In contrast, 100% of the animals receiving the
oral Vaxart vaccine survived.

“This is another clear demonstration of the ability of our oral
influenza vaccine to provide protection against divergent influenza
strains such as H5N1 avian flu,” said Wouter Latour, M.D., chief
executive officer of Vaxart. “This result complements the data from our
recent human challenge study, and solidifies the body of evidence
demonstrating that our oral vaccines have the potential to provide
improved protection against influenza compared to injectable inactivated
vaccines.”

The Phase 2 study was completed with support from Biomedical Advanced
Research and Development Authority (BARDA). Vaxart received a $13.9
million contract from BARDA in September 2015 to support the advanced
development of more effective influenza vaccines to ultimately improve
seasonal and pandemic influenza preparedness. The contract was increased
to $15.7 million in 2017.

The project has been funded in whole or in part with federal funds from
the Department of Health and Human Services’ Office of the Assistant
Secretary for Preparedness and Response; Biomedical Advanced Research
and Development Authority under Contract No. HHSO100201500034C.

About Vaxart

Vaxart is a clinical-stage biotechnology company focused on developing
oral recombinant protein vaccines based on its proprietary oral vaccine
platform. Vaxart’s vaccines are designed to generate broad and durable
immune responses that protect against a wide range of infectious
diseases and may also be useful for the treatment of chronic viral
infections and cancer. Vaxart’s vaccines are administered using a
convenient room temperature-stable tablet, rather than by injection.
Vaxart believes that tableted vaccines are easier to distribute and
administer than injectable vaccines and have the potential to
significantly increase vaccination rates. Vaxart’s development programs
include oral tablet vaccines that are designed to protect against
norovirus, seasonal influenza and respiratory syncytial virus (RSV), as
well as a therapeutic vaccine for human papillomavirus (HPV).

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
our strategy, prospects, plans and objectives, results from preclinical
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
“believe,” “could,” “potential,” “will” and other words and terms of
similar meaning. Examples of such statements include, but are not
limited to, statements relating to the Vaxart’s ability to develop and
commercialize its product candidates and clinical results and trial
data; and Vaxart’s expectations with respect to the advantages it
believes its oral vaccine platform can offer over injectable
alternatives, particularly for mucosal pathogens such as norovirus, flu
and RSV. Vaxart may not actually achieve the plans, carry out the
intentions or meet the expectations or projections disclosed in our
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 factors could cause
actual results or events to differ materially from these forward-looking
statements, including Vaxart’s ability to raise sufficient capital to
fund the continued development of its product candidates and complete
its planned studies and trials, 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 Vaxart may
experience manufacturing issues and delays; 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.

Contacts

Carl Mauch
Stern Investor Relations
212-362-1200
[email protected]