EPIX Pharmaceuticals Files Appeal with FDA Regarding Vasovist™ Approvable Letters; Company Remains Committed To Making Novel Blood-Pool Imaging Agent Available in U.S

Business Wire, June 30, 2006

CAMBRIDGE, Mass. -- EPIX Pharmaceuticals, Inc. (NASDAQ: EPIX), a developer of innovative pharmaceuticals for magnetic resonance imaging (MRI) which recently announced a definitive agreement to merge with Predix Pharmaceuticals Holdings, Inc., today announced that it has submitted a formal appeal to the U.S. Food and Drug Administration (FDA) asking the FDA to approve the Company's novel blood-pool imaging agent Vasovist(TM). The Company submitted the appeal to the Office of New Drugs of the FDA and has asked that an Advisory Committee be utilized as part of the appeal process. The Company expects that the Office of New Drugs will respond to the Company's submission within approximately 30 days, although any decision could be delayed if the Office of New Drugs grants the Company's request for an Advisory Committee.

"The submission of this appeal is the next step in a long process and represents a substantial undertaking for our company and underscores our confidence in the clinical profile and benefits of Vasovist," commented Dr. Andrew Uprichard, EPIX President and COO. "We are hopeful that we will have the opportunity to present the data from our four completed Phase III trials, as well as other data collected on Vasovist, to an Advisory Committee as part of the appeal process, and are continuing preparations accordingly."

Vasovist, EPIX's lead product candidate, is an injectable intravascular contrast agent designed to provide visual imaging of the vascular system through magnetic resonance angiography. EPIX's initial target indication for Vasovist is for use in magnetic resonance angiography imaging of non-coronary vascular disease. In October 2005, the European Medicines Agency granted marketing approval of Vasovist for all 25 member states of the E.U. Schering AG, Germany, EPIX's partner for Vasovist, began marketing Vasovist in Europe in the second quarter of 2006.

About EPIX

EPIX Pharmaceuticals, Inc., based in Cambridge, MA, discovers and develops innovative pharmaceuticals for imaging that are designed to transform the diagnosis, treatment and monitoring of disease. The Company uses its proprietary Target Visualization Technology(TM) to create imaging agents targeted at the molecular level, designed to enable physicians to use Magnetic Resonance Imaging (MRI) to obtain detailed information about specific disease processes. On April 3, 2006, EPIX announced a definitive agreement to merge with Predix Pharmaceuticals to create a specialty pharmaceutical company with capabilities in both therapeutics and imaging. To receive the latest EPIX news and other corporate developments, please visit the EPIX website at www.epixpharma.com.

About Predix

Predix, based in Lexington, MA, is a pharmaceutical company focused on the discovery and development of novel, highly selective, small-molecule drugs that target G-Protein Coupled Receptors (GPCRs) and ion channels. Using its proprietary drug discovery technology and approach, Predix has advanced four internally-discovered drug candidates into clinical trials and has five additional programs in preclinical development and discovery. Predix is expected to complete the first of at least two pivotal Phase III clinical trials for generalized anxiety disorder for its lead drug candidate, PRX-00023, in the second half of 2006. In addition to PRX-00023, Predix has three other clinical-stage drug candidates: PRX-03140 for the treatment of Alzheimer's disease, which is expected to enter Phase IIa later this year; PRX-08066 for the treatment of pulmonary hypertension (PH) and PH associated with chronic obstructive pulmonary disease, which recently completed a Phase Ib trial and is expected to enter Phase IIa in mid-2006; and, PRX-07034, which recently entered a Phase I trial and is expected to be developed for the treatment of obesity and also cognitive impairment associated with Alzheimer's disease or schizophrenia. Additional information about Predix can be found on the company's website at www.predixpharm.com.

Additional Information About the Merger And Where To Find It

EPIX has filed a registration statement on Form S-4 with the Securities and Exchange Commission containing a joint proxy statement/prospectus in connection with the proposed merger with Predix Pharmaceuticals. Investors and security holders are advised to read the joint proxy statement/prospectus (including any amendments or supplements thereto) regarding the proposed merger when it becomes available because it contains important information about EPIX, Predix and the proposed transaction and other related matters. The joint proxy statement/prospectus will be sent to stockholders of EPIX and Predix seeking their approval of the proposed transaction. Investors and security holders may obtain a free copy of the joint proxy statement/prospectus and any amendments or supplements thereto (when they are available) and other documents filed by EPIX at the Securities and Exchange Commission's web site at www.sec.gov. The joint proxy statement/prospectus and such other documents may also be obtained for free by directing such request to EPIX Pharmaceuticals, Inc. 161 First Street, Cambridge, Massachusetts, Attn: Investor Relations, tel: (617) 250-6000; e-mail: ahedison@epixpharma.com or Predix Pharmaceuticals Holdings, Inc., 4 Maguire Road, Lexington, Massachusetts 02421, Attn: Investor Relations, tel: (781) 372-3260; e-mail: investors@predixpharm.com.