Positive interim data from Aeterna Zentaris' AEZS-108 Phase 1/2 study on prostate cancer

Aeterna Zentaris Inc. (NASDAQ: AEZS) (TSX: AEZ) (the "Company"), today announced positive interim data for the Phase 1 portion of its ongoing Phase 1/2 study in castration and taxane-resistant prostate cancer with its targeted cytotoxic luteinizing hormone releasing hormone (LHRH) analog, AEZS-108. The data were presented by Jacek Pinski, M.D, Associate Professor of Medicine at the Norris Comprehensive Cancer Center of the University of Southern California, during a poster session on Saturday, September 24, 2011, at the European Society of Medical Oncology (ESMO) Congress currently being held in Stockholm, Sweden. The trial is being supported by a three year grant of about US$1.5 million from the National Institutes of Health.

Dr. Pinski stated, "Results for the Phase 1 portion of our clinical trial exceeded our expectations. In addition to proving to be very safe, AEZS-108 also demonstrated impressive efficacy even at low doses."

Juergen Engel, Ph.D., President and CEO of Aeterna Zentaris commented, "We thank Dr. Pinski and his colleagues for the exciting outcome of this early study, including the elegant demonstration of drug internalization in circulating tumor cells of treated patients. We now look forward to the Phase 2 portion of this study which will have more emphasis on therapeutic activity. It will also be interesting to see the results from the correlative studies to further strengthen the rationale of this personalized treatment approach."