AEterna Zentaris Announces Positive Preliminary Results for Phase 2 Study with LHRH-Receptor Targeted Cytotoxic Conjugate AEZS-108 in Ovarian Cancer

AEterna Zentaris Announces Positive Preliminary Results for Phase 2 Study with
LHRH-Receptor Targeted Cytotoxic Conjugate AEZS-108 in Ovarian Cancer

Preliminary evaluation after completion of treatment phase shows that
primary efficacy endpoint has been met for patients with advanced-stage
platinum-resistant, taxane-pretreated ovarian cancer.

QUEBEC CITY, Nov. 2 /PRNewswire-FirstCall/ - AEterna Zentaris Inc. (TSX: AEZ;
Nasdaq: AEZS) (the "Company"), a global biopharmaceutical company focused on
endocrine therapy and oncology, today announced positive efficacy data from a
Phase 2 study with its targeted cytotoxic peptide conjugate, AEZS-108
(formerly AN-152), in patients with platinum-resistant and taxane-pretreated
ovarian cancer. In a personalized healthcare approach, the study selected
patients with tumors expressing LHRH receptors, the key element in the
targeting mechanism of AEZS-108. Under coordination by Prof. Gunter Emons, MD,
Chairman of the Department of Obstetrics & Gynaecology at the University of
Gottingen, Germany, this open-label, multi-center and multi-national Phase 2
study 'AGO-GYN-5' is being conducted by the German AGO Study Group
(Arbeitsgemeinschaft Gynakologische Onkologie / Gynaecological Oncology
Working Group; www.ago-ovar.de), in cooperation with clinical sites in Europe.

Preliminary Results

All 43 patients with LHRH-receptor positive ovarian cancer who entered study
AGO-GYN-5 have completed their study treatment. A preliminary evaluation shows
that the study met its primary efficacy endpoint of 5 or more responders in 41
evaluable patients.
Responders, as well as patients with stable disease after completion of
treatment with AEZS-108, will now be followed to assess the duration of
progression-free survival and, ultimately, overall survival. More detailed
analyses, which will also include efficacy data from post-treatment follow-up
of the ovarian cancer patients, are currently in preparation and will be
presented at forthcoming scientific conferences.
Juergen Engel, Ph.D., AEterna Zentaris President and Chief Executive Officer
stated, "We are pleased with the progress of this project. The successful
completion of the recruitment and treatment phase and the apparent activity in
this difficult group of cancer patients is encouraging. This is the basis we
were looking for, in order to take the next steps in the further development
of AEZS-108 in gynaecological cancers and possibly also in prostate cancer."

About the AEZS-108 Phase 2 Program

AEZS-108 represents a new targeting concept in oncology using a cytotoxic
peptide conjugate which is a hybrid molecule composed of a synthetic peptide
carrier and a well-known cytotoxic agent, doxorubicin. The design of this
product allows for the specific binding and selective uptake of the cytotoxic
conjugate by LHRH-receptor-positive tumors. The binding of AEZS-108 to
cancerous cells that express these receptors results in its accumulation and
preferential uptake in the malignant tissue.
In a Phase 2 study program entitled, "The antitumoral activity and safety of
AEZS-108 (AN-152), a LHRH agonist linked doxorubicin in women with
LHRH-receptor positive gynaecological tumors", patients with tumors expressing
LHRH receptors are administered an intravenous infusion of 267 mg/m2 of
AEZS-108 over a period of 2 hours, every Day 1 of a 21-day (3-week) cycle. The
proposed duration of the study treatment is 6, 3-week cycles. Study AGO-GYN-5
is performed with 14 centers of the German Gynaecological Oncology Working
Group (AGO; www.ago-ovar.de), in cooperation with 3 clinical sites in Europe.
The program was planned to include up to 82 patients, up to 41 with a
diagnosis of platinum-resistant and taxane-pretreated ovarian cancer, and up
to 41 with disseminated endometrial cancer. For both indications, patient
recruitment was planned in 2 stages with 21 and 20 patients, respectively, and
the primary efficacy endpoint at the end of stage 2 was defined as 5 or more
patients with partial or complete tumor responses according to Response
Evaluation Criteria in Solid Tumors (RECIST) and/or Gynaecologic Cancer
Intergroup (GCIG) guidelines. Secondary endpoints include time to progression,
survival, toxicity, as well as adverse effects.

About Ovarian and Endometrial Cancer

Ovarian cancer is one of the most common gynaecologic malignancies and the
fifth most frequent cause of cancer death in women, with most of the cases
occurring in women between 50 and 75 years of age. Overall, ovarian cancer
accounts for 4% of all cancer diagnoses in women and 5% of all cancer deaths.
Approximately 26,000 new cases and 17,000 deaths from this disease are
estimated in the European community every year (Source: Gynaecologic Oncology,
Volume 92, Issue 3, March 2004, Pages 819-826).
Cancer of the endometrium is the most common gynaecologic malignancy and
accounts for 6% of all cancers in women. The majority of the cases occur in
postmenopausal women, with the largest number of women developing their
cancers during their sixth decade. Approximately 38,000 new cases and 9,000
deaths from this disease are estimated annually in Europe (Source: Annals of
Oncology 15:1149-1150, 2004).

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 required 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