LEXINGTON, Mass.--(BUSINESS WIRE)--EPIX Pharmaceuticals, Inc. (NASDAQ:EPIX) today announced that it has achieved an initial milestone under its collaboration with GlaxoSmithKline (NYSE:GSK) related to the first of three discovery stage programs. Using its proprietary, integrated computational-medicinal chemistry approach to drug discovery, EPIX has identified three lead candidates that will move forward into lead optimization in this first collaborative G-protein coupled receptor (GPCR) discovery program. Under the collaboration, EPIX is entitled to receive a $3 million milestone payment from GSK in the next 30 days.