Aphton Announces Appointment of Manfred Ruediger, Ph.D. to the Position of Chief Operating Officer

Aphton Corporation (NASDAQ:APHT) today announced the
appointment of Manfred Ruediger, Ph.D. to the newly created position
of Executive Vice President and Chief Operating Officer. Dr. Ruediger
will focus on business development, intellectual property,
manufacturing and project management. He will also be responsible for
helping to develop and implement strategies recently adopted by Aphton
as part of its evolution as a global oncology company. Dr. Ruediger
will also serve as a member of Aphton's Board of Directors.
   "We are very pleased to appoint Manfred to the position of 
Chief Operating Officer and we look forward to his contributions to 
both the management team and to the board," commented Patrick Mooney, 
M.D. Chairman and CEO of Aphton. "With more than 15 years in 
academia and industry, Manfred has extensive experience in research, 
development and operations. He is a seasoned biotech executive with 
a proven ability to build and organize teams around specific 
development goals."
   Dr. Ruediger served as Chief Executive Officer and Managing Board
Member of Igeneon AG ("Igeneon"), a clinical stage biopharmaceutical
company located in Vienna, Austria. Aphton acquired Igeneon in 
March 2005 to broaden Aphton's product portfolio and create a global
oncology company. Before being appointed Chief Executive Officer of
Igeneon, Dr. Ruediger served as Igeneon's Chief Operating Officer.
Prior to joining Igeneon, Dr. Ruediger held various executive
positions at Cardion AG, a biotechnology company, including the
positions of Executive Vice President, Chief Scientific Officer and
acting Chief Executive Officer, where he was responsible for both
in-licensing and out-licensing with leading biotech and pharma
companies.
   Dr. Ruediger holds a Ph.D. degree in biochemistry and protein
chemistry from the University of Tuebingen, Germany, and was assistant
professor at Technical University of Braunschweig, Germany.

   Strategic Pipeline

   Aphton continues to focus its efforts on broadening and making
progress in its research and development pipeline. An important
element of this strategy is the addition of Igeneon's products,
IGN101, a cancer vaccine designed to induce an immune response against
EpCAM positive tumor cells, and IGN311, a fully humanized antibody
against the Lewis Y antigen. Aphton also has a diverse pipeline of
pre-clinical and clinical products including active and passive
immunotherapies. Aphton believes that immunotherapies may have certain
advantages over other targeted therapies by including specificity that
may lead to better efficacy and decreased toxicities for patients.

   About Aphton

   Aphton Corporation, headquartered in Philadelphia, Pennsylvania is
a clinical stage biopharmaceutical company focused on developing
targeted immunotherapies for cancer. Aphton's products seek to empower
the body's own immune system to fight disease. Through the acquisition
of Igeneon AG in March 2005, Aphton acquired late-stage products,
IGN101, a cancer vaccine designed to induce an immune response against
EpCAM positive tumor cells, and IGN311, a fully humanized antibody
against the Lewis Y antigen. Aphton is currently seeking partners that
will support the further development of Insegia (G17DT immunogen), its
immunogen targeting the hormone gastrin. Aphton has strategic
alliances with sanofi-aventis for the development and
commercialization of Insegia related to cancers of the
gastrointestinal system and other cancers in North America and Europe;
Daiichi Pure Chemicals for the development, manufacturing and
commercialization of gastrin-related diagnostic kits; and Xoma for
treating gastrointestinal and other gastrin-sensitive cancers using
anti-gastrin monoclonal and other antibodies. For more information
about Aphton or its programs please visit Aphton's website at
http://www.aphton.com.

   Safe Harbor

   This press release includes forward-looking statements, including
statements about: (1) Aphton's belief regarding the strength of
Igeneon's product portfolio and such portfolio's ability to complement
Aphton's product portfolio; (2) Aphton's intent to broaden and
progress its research and development pipeline; (3) Aphton's belief
that immunotherapies have certain advantages over targeted therapies;
(4) Aphton's expectation regarding the purpose and effectiveness of
IGN101 and IGN311; and (5) Aphton's ability to find a viable partner
to financially support the further development of Insegia. These
forward-looking statements may be affected by the risks and
uncertainties inherent in the drug development process and in Aphton's
business. This information is qualified in its entirety by cautionary
statements and risk factor disclosure contained in Aphton's Securities
and Exchange Commission filings, including Aphton's report on Form
10-K filed with the Commission on March 16, 2005. Aphton wishes to
caution readers that certain important factors may have affected and
could in the future affect Aphton's beliefs and expectations and could
cause the actual results to differ materially from those expressed in
any forward-looking statement made by or on behalf of Aphton. These
risk factors include, but are not limited to, (1) Aphton's ability to
fund the further development of its research and development, (2)
Aphton's ability to successfully identify and consummate opportunities
to broaden and progress its research and development pipeline, (3)
scientific developments regarding immunotherapies, (4) Aphton's
ability to successfully integrate Igeneon's operations and product
portfolio with Aphton's operations and product portfolio, and (5) the
actual design, results and timing of preclinical and clinical studies
for both companies' products and product candidates.