AEterna Zentaris: New Data Published on its Ghrelin Antagonist Compound, AEZS-123...

AEterna Zentaris: New Data Published on its Ghrelin Antagonist Compound,
AEZS-123 (JMV2959), Supports its Use in Alcohol Addiction

Data published in July 7, 2009 Issue of Proceedings of the National
Academy of Sciences

QUEBEC CITY, July 7 /PRNewswire-FirstCall/ - AEterna Zentaris Inc. (NASDAQ:
AEZS; TSX: AEZ), a global biopharmaceutical company focused on endocrine
therapy and oncology, today announced publication in the renowned American
scientific journal, Proceedings of the National Academy of Sciences (PNAS), of
new data supporting the use of AEterna Zentaris' ghrelin receptor antagonist
compound, AEZS-123 (JMV2959), for the treatment of alcohol dependence that
involves ghrelin. Ghrelin is a hormone produced by the stomach and acting in
the brain. Compelling evidence obtained with the administration of AEZS-123,
and a ghrelin receptor mouse knockout model, highlights the role of ghrelin to
regulate the rewarding value of alcohol in a mouse model of alcohol
dependence. When ghrelin's actions are blocked, alcohol's effects on the
reward system are reduced.
The data show that mice treated with ghrelin increase their alcohol
consumption. When ghrelin's actions are blocked by administering ghrelin
receptor antagonists such as AEZS-123, mice no longer show preference for an
alcohol-associated environment - in other words, alcohol is no longer able to
produce its addictive effects that include reward searching behaviour (akin to
craving in alcoholic patients).
The work, coordinated by AEterna Zentaris, emerged from an international
collaboration between the research groups of Prof. Suzanne Dickson and Prof.
Jörgen Engel who performed the pharmacology work at the Sahlgrenska Academy,
Gothenburg, Sweden, and the research group of Prof. Jean Martinez who
synthesized the tested compound AEZS-123 at the Institut des biomolecules Max
Mousseron, Montpellier, France.
Suzanne Dickson, Professor of Physiology and a leading expert in appetite
regulation said, "Ghrelin's action in the brain may be of importance for
several addictions, including chemical drugs such as alcohol and even food."
Daniel Perrissoud, Senior Director of Project Management at AEterna Zentaris
and one of the authors of the paper stated, "The discovery of the Gothenburg
team that the reward system is a target of ghrelin effects, opens new
development opportunities for our proprietary ghrelin receptor antagonists. In
the field of addiction, the clinical proof of efficacy can be obtained in a
more time- and cost-effective manner than in the field of obesity, as
short-term clinical laboratory paradigms can be used for the clinical
evaluation."
The article entitled, "Requirement of Central Ghrelin Signaling for Alcohol
Reward" appears today in the July 7, 2009 issue of Proceedings of the National
Academy of Sciences (PNAS 2009; 106:11318-11323) and was published on line on
June 29, 2009 in the early edition of the journal.

About AEterna Zentaris' Ghrelin Antagonist Program

Ghrelin is a natural peptide hormone produced by the stomach that increases
appetite and induces accumulation of fat tissue. The discovery of ghrelin and
its receptors opens up new opportunities for the treatment of obesity and
eating disorders through the use of ghrelin antagonists to suppress appetite
and fat deposition.
In 2004, AEterna Zentaris signed two agreements for the development of ghrelin
antagonists with the Institut des biomolecules Max Mousseron of the University
of Montpellier, France, directed by Prof. Jean Martinez, and with the
Department of Experimental and Environmental Medicine of the University of
Milan, Italy, directed by Prof. Vittorio Locatelli. The research projects were
targeting the chemical synthesis and pharmacological investigation of new
compounds acting as ghrelin antagonists.
In 2006, AEterna Zentaris reported first in vivo pharmacological data on the
capability of proprietary ghrelin receptor antagonists to selectively inhibit
food intake.
At the annual meetings of the American Endocrine Society (ENDO) of 2007 and
2008, Prof. Denis Richard of the Centre de recherche de l'Institut de
cardiologie et de pneumologie de Quebec, in collaboration with AEterna
Zentaris, presented posters showing that the ghrelin receptor antagonist
AEZS-123 reduced body weight gain and fat accumulation in an animal model of
diet-induced obesity.

About the Food and Alcohol Addiction Market

There is no safe and effective appetite suppressant currently on the market.
It is estimated that between 34 million and 61 million Americans are obese,
and the worldwide incidence of obesity is increasing by an estimated 1% per
year.
Alcohol dependence is a complex and chronic disease which leads to adverse
consequences affecting not only the patients but also their immediate family
and has a profound economic burden on society. The annual costs to the United
States are estimated to be US$185 billion for alcohol addiction. In 2005, the
number of people affected by alcohol problems in the United States was
estimated at 15.4 million.

About AEterna Zentaris Inc.

AEterna Zentaris Inc. is a global biopharmaceutical company focused on
endocrine therapy and oncology, with proven expertise in drug discovery,
development and commercialization. News releases and additional information
are available at www.aezsinc.com.

Forward-Looking Statements

This press release contains forward-looking statements made pursuant to the
safe harbor provisions of the U.S. Securities Litigation Reform Act of 1995.
Forward-looking statements involve known and unknown risks and uncertainties,
which could cause the Company's actual results to differ materially from those
in the forward-looking statements. Such risks and uncertainties include, among
others, the availability of funds and resources to pursue R&D projects, the
successful and timely completion of clinical studies, the ability of the
Company to take advantage of business opportunities in the pharmaceutical
industry, uncertainties related to the regulatory process and general changes
in economic conditions. Investors should consult the Company's quarterly and
annual filings with the Canadian and U.S. securities commissions for
additional information on risks and uncertainties relating to the
forward-looking statements. Investors are cautioned not to rely on these
forward-looking statements. The Company does not undertake to update these
forward-looking statements. We disclaim any obligation to update any such
factors or to publicly announce the result of any revisions to any of the
forward-looking statements contained herein to reflect future results, events
or developments except if we are requested by a governmental authority or
applicable law.
SOURCE AETERNA ZENTARIS INC.

Investor Relations: Ginette Vallieres, Investor Relations Coordinator, (418)
652-8525 ext. 265, gvallieres@aezsinc.com; Media Relations: Paul Burroughs,
Director of Communications, (418) 652-8525 ext. 406, pburroughs@aezsinc.com