( Second generationpyridopyrazine-ure...)terna Zentaris Discloses First In Vitro Data for its PI3K,,,Inhibitors at the AACR Annual Meeting in Los Angeles,Health

Second generation pyridopyrazine-urea derivative compound series show highly selective PI3K-inhibition which could be valuable for cancer treatment

QUBEC CITY, Canada, April 16, 2007 terna Zentaris Inc. (TSX: AEZ; Nasdaq: AEZS), a global, pure play biopharmaceutical company focused on endocrine therapy and oncology, today presented an abstract outlining first in vitro data on its pyridopyrazine derivatives with high selectivity for PI3K inhibition, at the American Association for Cancer Research (AACR) Annual Meeting being held this week at the Los Angeles Convention Center in Los Angeles, California.

Results

The poster #2379 entitled, New Generation of Anilino-Substituted Pyridopyrazine-Urea Derivatives Show Highly Selective PI3K-Inhibition, reviewed for the first time, results for a preclinical development program on a new generation of pyridopyrazine derivatives which clearly indicate that these drug candidates selectively inhibit PI3K.

Furthermore, an optimization process of our already known aryl-pyridopyrazine series led to the identification of a new lead compound in this series. A medicinal chemistry program was then initiated which resulted in the synthesis of new anilino-substituted pyridopyrazines. Out of this second generation series, several derivatives also with highly-selective PI3K inhibition as well as improved cellular efficacy and better drug-like properties, were identified.

Conclusions