AEterna Zentaris Inc. is turning its attention to perifosine, the promising multiple myeloma drug partnered with Keryx Biopharmaceuticals Inc., as its cetrorelix agreement with Sanofi-Aventis U.S. comes to an end.

Sanofi and the Quebec City-based biotech officially will end their partnership Jan. 9 for cetrorelix, a luteinizing hormone-releasing hormone antagonist, but the move has been expected since early this month when the firms reported disappointing data from a second pivotal study in benign prostatic hyperplasia.

Results from the Phase III European study showed that cetrorelix produced no clear differences in overall efficacy vs. placebo, dashing the few hopes that had remained following the failure of the North American trial in August. (See BioWorld Today, Aug. 18, 2009.)

AEterna signed the deal with Bridgewater, N.J.-based Sanofi in March, picking up $30 million in up-front cash, with the possibility for up to $135 million in milestones plus royalties. (See BioWorld Today, March 9, 2009.)

The company is hoping for better luck with perifosine, which made a splash at this year's American Society of Hematology meeting in New Orleans. AEterna and New York-based Keryx and recently began Phase III testing in relapsed and refractory multiple myeloma under a special protocol assessment. (See BioWorld Today, Aug. 4, 2009.)

On its own, the company is working on AEZS-108, a targeted doxorubicin conjugate, which recently completed Phase II testing in ovarian and endometrial cancers, and also developing AEZS-130, a ghrelin agonist, as a diagnostic test for adult growth hormone deficiency.

Shares of AEterna (NASDAQ:AEZS) closed at 82 cents Friday, down 4 cents.