Aeterna Zentaris selects optimized Erk inhibitor molecule for further development

Aeterna Zentaris Inc. (NASDAQ: AEZS) (TSX: AEZ) (the "Company") today announced it has selected an optimized Erk inhibitor molecule for development, thus achieving another important milestone in the development of a new class of potential cancer therapies.

The MAPK pathway represents a prime target for therapeutic intervention in cancer. Recently approved compounds demonstrate significant antitumor activities and survival benefits for B-Raf and Mek inhibitors. Erk inhibitors may be preferred agents in tumors with aberrant MAPK pathway activity, e.g. in tumors with mutated or wildtype B-Raf, mutated or wildtype ras, and in tumors with acquired resistance to Raf and Mek inhibitors.

At the 2014 American Association for Cancer Research's annual meeting, the Company presented an abstract of its work on an Erk inhibitor molecule called "AEZS-134". The abstract was selected by participants in the meeting as one of the 11 high-impact abstracts out of hundreds presented on the topic. Subsequently to this recognition, the Company continued its efforts on the Erk inhibitor program, including identification of an optimized molecule.

An optimized Erk inhibitor compound, AEZS-140, and back-up candidates were identified as a result of the development efforts. AEZS-140 and the back-up candidates demonstrate improved plasma exposure in rodents as well as enhanced anti-tumor efficacy in comparison to the previous lead compound, AEZS-134. Furthermore, AEZS-140 was profiled against several clinical Raf, Mek and Erk inhibitors and demonstrated very competitive activity.

The Company will proceed with the next development steps for AEZS-140 and the back-up compounds, including in depth profiling in vitro and, also, further in vivo tumor models. The Company is seeking proposals from parties who are interested in either co-developing or licensing the compounds.

David A. Dodd, Chairman and CEO of Aeterna Zentaris, commented, "Our strategy includes leveraging some of our promising early-stage drug candidates in order to generate potential long-term value without having to invest in their development. We are pursuing this strategy with respect to our Erk inhibitor development program. A therapeutic agent arising from this program could represent a novel approach to treating types of cancers with acquired resistance to Raf and Mek inhibitors. Our business development team is already engaged in discussions with parties who have previously expressed an interest in our work with Erk inhibitors."