PlenaxisTM is the first gonadotropin releasing hormone (GnRH) antagonist available as a depot formulation. PlenaxisTM is indicated for the palliative treatment of men with advanced symptomatic prostate cancer, in whom LHRH agonist therapy is not appropriate and who refuse surgical castration, and have one or more of the following: (1) risk of neurological compromise due to metastases, (2) ureteral or bladder outlet obstruction due to local encroachment or metastatic disease, or (3) severe bone pain from skeletal metastases persisting on narcotic analgesia. PlenaxisTM is not indicated for use in women or children.

Commenting on the approval, Malcolm L. Gefter, Ph.D., PRAECIS' Chairman and Chief Executive Officer, stated, "We are delighted with the approval, and would like to thank the FDA for diligently working with us to make this drug available for those prostate cancer patients who are most in need. The approval of PlenaxisTM represents years of dedication to drug discovery and development at PRAECIS to bring an innovative product to the market and marks an important milestone in our transition to a fully integrated pharmaceutical company. More importantly, this approval will bring a valuable therapy to those patients in the indicated population who have limited or no other treatment options available."

For safety reasons, PlenaxisTM is approved with marketing restrictions under 21 CFR 314, Subpart H, and will be available only to physicians who enroll in the PLUS (PLenaxisTM User Safety) Program.

Commenting on the PLUS Program, William K. Heiden, PRAECIS' President and Chief Operating
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Contact: Kevin F. McLaughlin, PRAECIS
781-795-4274
Porter Novelli
25-Nov-2003