Aeterna Zentaris Receives Positive Opinion for Orphan Medicinal Product Designation for AEZS-108 for the Treatment of Ovarian Cancer from the Committee for Orphan Medicinal Products of the European Medicines Agency

QUEBEC CITY, May 17 /PRNewswire-FirstCall/ - Aeterna Zentaris Inc. (NASDAQ: AEZS, TSX: AEZ), (the "Company") a late-stage drug development company specialized in oncology and endocrinology, today announced that it has received a positive opinion for orphan medicinal product designation from the Committee for Orphan Medicinal Products (COMP) of the European Medicines Agency, for its compound AEZS-108 for the treatment of ovarian cancer. AEZS-108, the Company's doxorubicin targeted conjugate compound, is currently in a Phase 2 trial in advanced ovarian and advanced endometrial cancer in Europe.

Juergen Engel, Ph. D., President and CEO of Aeterna Zentaris stated, "We are very pleased with AEZS-108 gaining orphan medicinal product designation for ovarian cancer from European authorities, especially after having been recently granted orphan-drug designation by the FDA. This means that with both these orphan designations, AEZS-108 would be provided with extra market exclusivity protection in Europe as well as in the United States for the treatment of ovarian cancer. We now look forward to reporting the final results from our ongoing European Phase 2 study in ovarian and endometrial cancer, later this year."

About Orphan Medicinal Product Designation

Orphan medicinal product designation is granted by the European Commission, following a positive opinion from the COMP, to a medicinal product that is intended for the diagnosis, prevention or treatment of a life-threatening or a chronically debilitating condition affecting not more than five in 10,000 persons in the Community when the application for designation is submitted.

Orphan medicinal product designation provides the sponsor with access to the Centralized Procedure for the application for marketing authorization, protocol assistance, up to a 100% reduction in fees related to a marketing authorization application, pre-authorization inspection and post-authorization activities, and could provide ten years of market exclusivity in EU, once approved for the treatment of ovarian cancer.

About Ovarian 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 2004; 92:819-26). The National Cancer Institute estimates that in 2009, in the United States alone, there were 21,550 news cases of ovarian cancer and 14,600 related deaths.

About AEZS-108

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.

About Aeterna Zentaris Inc.

Aeterna Zentaris Inc. is a late-stage drug development company specialized in oncology and endocrine therapy. 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.