U.S. Food and Drug Administration Accepts Biologics License Application for PaxVax's Single-Dose Oral Cholera Vaccine Vaxchora

Vaxchora™ also granted priority review status by FDA as a vaccine
candidate addressing a tropical disease

REDWOOD CITY, Calif. – December 16, 2015 – PaxVax Inc., a fully
integrated specialty vaccine company committed to developing and
commercializing innovative vaccines against infectious diseases, today
announced that the U.S. Food and Drug Administration (FDA) has
accepted for filing and review the Biologics License Application (BLA)
for its affiliate PaxVax Bermuda Ltd.'s single-dose oral cholera
vaccine Vaxchora™. PaxVax also announced today that the FDA has
granted Vaxchora priority review status. If licensed, Vaxchora would
be the only vaccine in the U.S. against cholera and PaxVax's second
FDA-licensed vaccine after Vivotif®(typhoid fever vaccine).

"Travelers residing in the U.S. currently have very few options to
protect themselves against cholera when going abroad, and we are
pleased with the progress we are making in bringing an effective
single-dose cholera vaccine to the U.S. market," said Nima Farzan,
Chief Executive Officer of PaxVax, Inc. "We are also pleased to
announce that Vaxchora has been granted priority review status, a
critical step in the process of being awarded a Priority Review
Voucher. The potential of being granted a voucher has been an
important incentive for PaxVax and our decision to bring this vaccine
to the U.S. market."

The BLA, which was submitted on October 16, 2015, is based on
successful results from a 10 and 90-day cholera challenge trial, as
well as two other safety and immunogenicity trials in healthy adults.
More than 3,000 participants were enrolled in the Phase 3 trials that
evaluated Vaxchora at sites in Australia and the United States.
Vaxchora also successfully met the Phase 3 primary endpoints and
demonstrated efficacy in an immunogenicity study of older adults 46 to
64 years of age. The FDA's action date for the Vaxchora BLA is June
15, 2016.

The cholera strain used in Vaxchora is CVD 103-HgR, which was
in-licensed from the University of Maryland School of Medicine's
Center for Vaccine Development in 2010. If approved, Vaxchora will be
commercialized through the existing PaxVax marketing and sales
infrastructure, which currently commercializes Vivotif.

Cholera is an acute intestinal diarrheal infection caused by toxigenic
Vibrio cholerae bacteria generally acquired by ingesting contaminated
water or food. According to the World Health Organization, the global
disease burden is estimated to be three to five million cases and
100,000 to 120,000 deaths per year. Cholera often manifests as
explosive epidemics that rapidly move through populations, such as the
recent outbreak in Iraq and those that occurred in Peru and Haiti in
1991 and 2010, respectively. The FDA has identified Cholera as one of
the eligible neglected tropical diseases under its Priority Review
Voucher program.