Pfizer and Ergonex Pharma GmbH have entered into an agreement under which Pfizer will acquire terguride, an oral, potent antagonist of 5-HT2B and 5-HT2A (serotonin) receptors, in development for Pulmonary Arterial Hypertension (PAH). Pfizer will complete the ongoing Phase II trial and will have exclusive worldwide rights to commercialize terguride for PAH, excluding Japan. Ergonex will be eligible to receive milestone payments and royalties on the sales of terguride for PAH.

Terguride has received orphan drug designation in both the U.S. and in the EU for the treatment of PAH. Terguride is also currently approved in Japan for the treatment of Hyperprolactinemia.

"Pfizer's unique business unit structure positions us to advance a broad portfolio of innovative research programs designed to lead to a diversity of products, including highly specialized ones in disease areas like PAH," said Geno Germano, president, Pfizer Specialty Care Business Unit."In the case of terguride, we are pleased that we can support its continued development given our commitment to advancing the science in PAH and to bringing new, potentially disease modifying treatments to patients."

Rudolf Reiter, chief executive officer of Ergonex Pharma, commented, "The serotonin hypothesis of PAH has been around for a long time. The clinical study of terguride in PAH is a challenging and demanding endeavor for us and we are excited about this agreement with Pfizer as it ensures continuity of development and advances our understanding of this pathway."