A German subsidiary of AEterna Laboratories Inc. is looking to further its drug development plans by way of a new collaboration with an old partner, Solvay Pharmaceuticals BV.

Zentaris GmbH, which is fully owned by AEterna, entered an agreement with Solvay to jointly advance development of a new low-molecular-weight and orally bioavailable peptidomimetic antagonist of LHRH (luteinizing hormone-releasing hormone). Not coincidentally, the LHRH-antagonizing mechanism of action is along the lines of another LHRH antagonist, Cetrorelix, in joint Phase II development by the companies.

"I am very pleased with this vote of confidence from Solvay Pharma for our LHRH antagonist platform," Gilles Gagnon, president and CEO of Quebec City, Quebec-based AEterna, told BioWorld Today. "I don't want to talk on behalf of Solvay, but this is some kind of succession planning for its portfolio. We are very pleased with the magnitude of the agreement, especially at this very early stage of the development of the compound."

Upon signing the agreement, Frankfurt, Germany-based Zentaris will receive $5 million, which covers an up-front payment and reimbursement for prior development costs. Having achieved proof of principle regarding oral bioavailability, the company said it expects to have a preclinical candidate later this year.

Potential indications include endometriosis, uterus myoma and benign prostatic hyperplasia (BPH), as well as malignant disorders such as breast and prostate cancer. Brussels, Belgium-based Solvay secured exclusive worldwide rights to all gynecological indications and BPH, while Zentaris retains exclusive rights to all other indications, including oncology.

"Solvay has a huge franchise in women's health, so endocrinology is more in its core business," Gagnon said, adding that the early stage program soon would progress toward pharmacology studies related to the oral formulation, metabolic stability and selectivity. "Then they will have to make a decision as to whether they have a drug candidate or not, and then go to the clinic."

The arrangement calls for Solvay to fund further preclinical and clinical development activities, which will be carried out by Zentaris, and to make milestone payments. Gagnon said the agreement precludes him from providing more specific financial terms, though he acknowledged that Zentaris would receive royalties on sales.

The already-partnered product, Cetrorelix, is in Phase II studies for endometriosis, uterus myoma and BPH. It is sold for in vitro fertilization as Cetrotide by Geneva-based Serono SA. Cetrorelix was licensed to Solvay in November 2002, and soon after AEterna acquired Zentaris. (See BioWorld Today, Jan. 2, 2003.)

Also in the LHRH antagonist program, Zentaris is evaluating D-63153 in early Phase II studies for prostate cancer, an indication for which Zentaris' product Teverelix is in Phase I.

Another Phase II product, Perifosin, is a signal-transduction inhibitor being assessed in six tumor types through a collaboration with New York-based Access Oncology Inc. Two late-stage preclinical candidates belong to the taxane class. Beyond cancer, Zentaris is testing an anti-infective product called Impavido (miltefosine).

"I'm very pleased with the robustness and magnitude of this pipeline," Gagnon said. "We are very pleased with this agreement, especially at this stage of development when the risk is highest, to have a company making such a commitment."

AEterna's stock (NASDAQ:AELA) gained 3 cents Friday to close at $3.73.