Hookipa Announces Formation of Scientific Advisory Board

Vienna Austria, January 8, 2013 - Hookipa Biotech AG, a vaccine biotech start up pioneering a
new class of vaccines, today announced the formation of its Scientific Advisory Board (SAB). The
SAB is chaired by Emeritus Prof. Dr. Paul-Henri Lambert (PhD), former Chief of Vaccine Research and
Development for the WHO Global Program for Vaccines and Immunizations. The members include
distinguished scientists and experienced industrial experts: Emeritus Prof. Dr. Stanley Plotkin (MD),
Prof. Dr. Michael Mach (PhD), Dr. Arnaud Marchant (MD, PhD) and Prof. Dr. Franz Heinz (PhD). The
SAB will provide expert advice to the Company on a broad range of topics related to research,
development, manufacturing, quality control, medical, regulatory, and commercial aspects of the
Company’s Vaxwave® platform and specific vaccine targets.

“We are honored to have these eminent scientists and opinion leaders serving our Scientific Advisory
Board,” said Dr. Katherine Cohen, Chief Executive Officer of Hookipa Biotech. “They will provide
invaluable insight and guidance to advance our novel Vaxwave® technology platform for generating a
wave of new vaccines.”

“I am happy to chair the Scientific Advisory Board of Hookipa”, said Dr. Paul-Henri Lambert.
“Hookipa holds a promising vaccine technology platform for addressing the need of CD8+ T-cell and
neutralizing antibody immune responses. The seasoned industrial team at Hookipa is making rapid
progress towards the development of new generation vaccines.”

“I am very pleased to support Hookipa to develop a very innovative class of vaccine products which
has the potential to meet the current medical challenges,” commented Dr. Stanley Plotkin.

Scientific Advisory Board:

Emeritus Prof. Dr. Paul-Henri Lambert (PhD)

Dr. Paul-Henri Lambert led the Immunology Research and Training Program of the WHO, and as
professor in the Department of Pathology, University of Geneva, supervised the associated research
laboratories at the Universities of Geneva and Lausanne (1975-1987).

In 1987, he was appointed Chief of Microbiology and Immunology at WHO; since 1994, he was Chief
of Vaccine Research and Development for the WHO Global Program for Vaccines and Immunizations.
He is directly associated with the Center of Vaccinology, at the University of Geneva.
Dr. Paul-Henri Lambert is now also Director of the International Advanced Course of Vaccinology
organized by the Fondation Mérieux and University of Geneva, a member of several international
scientific boards, and is author or co-author of over 400 publications.

Emeritus Prof. Dr. Stanley Plotkin ( MD)

Dr. Stanley A. Plotkin is Emeritus Professor at the University of Pennsylvania and Adjunct Professor at
the Johns Hopkins University. Until 1991, he was Professor of Pediatrics and Microbiology at the
University of Pennsylvania, Professor of Virology at the Wistar Institute, and at the same time
Director of Infectious Diseases and Senior Physician at the Children’s Hospital of Philadelphia. In
1991, Dr. Plotkin left the University to join the vaccine company Pasteur-Mérieux-Connaught (now
known as Sanofi Pasteur), based at Marnes-la-Coquette, outside Paris, where he was Medical and
Scientific Director for seven years. Currently, Dr. Plotkin is consultant to vaccine manufacturers,
biotechnology companies, and non-profit research organizations as principal of Vaxconsult, LLC.

Dr. Plotkin attended New York University, where he received a B.A. degree, and the State University
of New York Medical School in Brooklyn, where he received an MD degree in 1956. His subsequent
career included internship at Cleveland Metropolitan General Hospital, residency in pediatrics at the
Children’s Hospital of Philadelphia and the Hospital for Sick Children in London, and three years with
the Epidemic Intelligence Service of the Centers for Disease Control of the US Public Health Service.
His bibliography includes more than 700 articles; he has edited several books including the standard
textbook on Vaccines, now in its 6th edition. He developed the rubella vaccine now in standard use
throughout the world, is co-developer of the newly licensed pentavalent rotavirus vaccine, and has
worked extensively on the development and application of other vaccines including anthrax, oral
polio, rabies, varicella, and cytomegalovirus.

Prof. Dr. Michael Mach (PhD)

Dr. Mach is Professor for Virology at the Institute of Virology, University Erlangen-Nürnberg. His
research interest centers on Herpes virus envelope glycoproteins with emphasis on viral
morphogenesis and the humoral immune response. Dr. Mach has studied pharmacy and received his
PhD from the University of Erlangen-Nürnberg, Germany. Following a post-doctoral stay at the
University of Washington, Seattle, USA, Dr. Mach returned to the University of Erlangen-Nürnberg as
Professor for Virology in 1993.

Dr. Arnaud Marchant (MD, PhD)

Arnaud Marchant, MD, PhD, Université Libre de Bruxelles, is conducting research in the field of
infectious disease and vaccine immunology. He developed a research program in early-life
immunology during his post-doctoral stay at the Medical Research Council Laboratories, The Gambia,
and Weatherall Institute for Molecular Medicine, Oxford. He is currently a senior research associate
at the Fonds de la Recherche Scientifique, Belgium, and heads a research group at the Institute for
Medical Immunology of the Université Libre de Bruxelles. Dr. Marchant is also Scientific Director of
ImmuneHealth, a non-profit research center specialized in clinical immunology.

Prof. Dr. Franz Heinz (PhD)

Dr. Franz X. Heinz is Full Professor of Virology at the Medical University of Vienna and since 2004
Director of the Department of Virology. His major research achievements and interests are in the
area of flaviviruses, including vaccine development, molecular antigenic structure and immune
responses, mechanisms of virus entry and viral epidemiology. From 1987 to 1993 Dr. Heinz was a
member of the WHO steering committee for the development of dengue and Japanese encephalitis
vaccines and from 2006 to 2011 he served on the Scientific Advisory Board of the vaccine
manufacturer Intercell. Currently Franz X. Heinz is a member of the National Academy of Germany
‘Leopoldina’ and a core member of the European Academy of Microbiology, as well as a member of
the Scientific Advisory Boards of the Robert-Koch Institute in Berlin and the Bernhard Nocht Institute
for Tropical Medicine in Hamburg.

About Hookipa Biotech

Hookipa Biotech, founded in Vienna, Austria in summer 2011, develops a new class of innovative
prophylactic and therapeutic vaccines based on its proprietary Vaxwave® technology.
The Vaxwave® technology is a novel vaccine platform using a replication-defective viral vector for the
prevention and treatment of multiple infectious diseases and cancer. The platform is one of the
most promising new technologies for next generation vaccines due to its ability to stimulate both
potent B-cell and CD8+ T-cell immune responses. Vaxwave® has been validated in various disease
models. Unlike other vectors, Vaxwave® vaccines can be administered repeatedly to boost the
immune system.

In October 2011, Hookipa raised €7 million from internationally renowned venture capital investors,
Sofinnova Partners and Forbion Capital Partners. The company currently focuses on the
development of its lead vaccine candidate HB101 and plans to further industrialize the Vaxwave®
technology and build a robust product pipeline. Hookipa has recently moved into its state-of-the-art
BSL2 facility at the Campus Vienna Biocenter.

Dr. Katherine Cohen
Chief Executive Officer
Hookipa Biotech AG
Helmut-Qualtinger-Gasse 2
1030 Vienna, Austria