March 31, 2004

News Release: AEterna subsidiary Zentaris reports positive preclinical results from novel pyrazole compound - Results indicate ZEN-014 as a new candidate for the development of a potent anticancer drug

AEterna Laboratories Inc. (TSX: AEL; Nasdaq: AELA) and its subsidiary Zentaris GmbH report that positive preclinical results of their novel tubulin-inhibitor ZEN-014 were presented earlier today at the American Association for Cancer Research (AACR) meeting in Orlando, Florida.

ZEN-014 is a novel pyrazole derivative that was discovered by Zentaris. It represents a new class of small molecule tubulin binders with antiangiogenic properties which are assumed to be novel highly potent anticancer drugs with blockbuster potential. ZEN-014 inhibits tubulin polymerization with an IC50 of 1.3 (micro)M. The treatment with non-toxic concentrations (10 nM) of ZEN-014 inhibits endothelial cell sprouting and vessel formation. Cancer cells (KB/HeLa) were arrested completely in the G2M phase of mitosis at nanomolar concentrations (IC50: 34 nM) and subsequently underwent apoptosis. Several apoptotic parameters as cell membrane alterations, increase of caspase 3 and 7 activity, DNA fragmentation and inactivation of the Bcl-2 protein are detectable in U937 cancer cells after treatment with nanomolar concentrations of ZEN-014.

The compound shows an excellent antitumor activity profile in a broad panel of tumor cell lines (average IC50 of 40 nM) including paclitaxel and vincristine resistant cells. ZEN-014 exhibits promising in vivo activity in a renal cell carcinoma model at a dose of 50 mg/kg after oral application.

'These excellent results again show the capability of our own drug discovery unit which is the core for the continuous supply of new development candidates and essential for the growth of our Company', said Prof. Dr. Jurgen Engel, Executive Vice President, Global R&D and Chief Operating Officer at AEterna, Chairman and Managing Director of Zentaris GmbH.

Based on these excellent in vitro and in vivo activities, ZEN-014 is a promising new candidate for further preclinical development. ZEN-014 combines antiproliferative activity at nanomolar concentrations with strong inhibition of angiogenesis.

About AEterna Laboratories

AEterna Laboratories Inc. along with its wholly-owned subsidiary Zentaris GmbH, is a biopharmaceutical company with an extensive product portfolio, including two marketed products and several other product candidates under development in oncology, endocrinology and infectious diseases. Cetrotide(R) (Cetrorelix) is sold in the U.S., Europe and several other countries to the in vitro fertilization market, and is in Phase II clinical trials for endometriosis, uterus myoma and enlarged prostate (BPH). Impavido(R) (Miltefosine) is sold for black fever and has successfully completed a Phase III trial in parasitic skin disease. Neovastat(R) is in a Phase III trial for non-small cell lung cancer. Perifosine, the first orally-active AKT inhibitor, is in Phase II trials for multiple cancers. Several other clinical programs are underway with various potential development candidates, supported by a worldwide network of scientific and marketing partnerships. Furthermore, AEterna benefits from a discovery platform of 100,000 molecules, which is generating promising new compounds.

In addition, AEterna owns 62% of Atrium Biotechnologies Inc., which develops and markets active ingredients and specialty chemicals in the health and personal care industry for the cosmetics, pharmaceutical, chemical and nutritional sectors. In 2003, Atrium sales exceeded $120 million.

AEterna shares are listed on the Toronto Stock Exchange (AEL) and the NASDAQ National Market (AELA). News releases and additional information about AEterna are available on its Web site at www.aeterna.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.
SOURCE AETERNA LABORATORIES INC.

AEterna Laboratories: Media Relations: PaulBurroughs, (418) 652-8525, ext. 406, (418) 573-8982 cell.,This email address is being protected from spambots. You need JavaScript enabled to view it. ; Investor Relations: Jacques Raymond,(418) 652-8525, ext. 360, (514) 703-5654 cell.,This email address is being protected from spambots. You need JavaScript enabled to view it.; U.S. Investor Relations: Lippert-Heilshorn &Associates: Kim Golodetz, (212) 838-3777, This email address is being protected from spambots. You need JavaScript enabled to view it. or Bruce Voss,(310) 691-7100, This email address is being protected from spambots. You need JavaScript enabled to view it.; Europe: Zentaris GmbH: Dr. Mathias Pietras,+ 49 69 42 602 3423, fax: + 49 69 42 602 3444, This email address is being protected from spambots. You need JavaScript enabled to view it.,www.zentaris.com(AEL. AELA)

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