PRAECIS PHARMACEUTICALS INCORPORATED Appoints Prem Das as Senior Vice President, Technology Partnerships

PRAECIS PHARMACEUTICALS INCORPORATED (NASDAQ: PRCS)
today announced that O. Prem Das, Ph.D. has joined the Company as
Senior Vice President, Technology Partnerships. Dr. Das will be
responsible for the establishment and management of strategic
partnerships relating to DirectSelect(TM), the Company's innovative
drug discovery technology. DirectSelect(TM) is based on DNA-tagged
small molecule libraries that are ultra-large, enable rapid screening
without robotics and can potentially access targets difficult to
handle using other drug discovery methods. Dr. Das will report to
Kevin F. McLaughlin, President and Chief Executive Officer, and will
serve as a member of PRAECIS' senior management team.

   "Prem's experience in technology licensing and his creativity in
structuring strategic transactions is a timely and important addition
to the PRAECIS management team, as we focus our efforts on leveraging
the power of DirectSelect(TM) to support external partnerships as well
as to expand our own proprietary development pipeline," stated Mr.
McLaughlin.

   Dr. Das commented, "I am excited to join PRAECIS, especially at a
time when the Company is executing the first phase of its strategic
plan for DirectSelect(TM). By entering into the recent pilot studies
with Gilead and GlaxoSmithKline, PRAECIS is now poised to broaden the
reach of its proprietary technology through corporate alliances and
collaborations. I look forward to working closely with Kevin and the
management team to realize the full potential of this technology and
develop a leading discovery-based pharmaceutical business."

   Dr. Das brings to PRAECIS strong scientific credentials, proven
expertise and a record of success in business development. Prior to
joining PRAECIS, Dr. Das served for three years as the Director of the
Office of Technology Development at Harvard Medical School, and for
nearly three years in a similar capacity at Memorial Sloan-Kettering
Cancer Center. In these positions, he was responsible for overseeing
licensing negotiations and during his tenure, successfully negotiated
a significant number of important out-licensing agreements with both
small and large pharmaceutical companies, as well as many sponsored
research, collaboration and clinical trial agreements. Previously, Dr.
Das was Director of Business Development for Cadus Pharmaceutical
Corporation, and earlier had founded and led a start-up biotechnology
company. Dr. Das also has over 15 years of experience in academic
research.

   Dr. Das holds a Ph.D. in Biological Chemistry from Massachusetts
Institute of Technology and a M.Sc. in Chemistry from the Indian
Institute of Technology at Kanpur.

   About PRAECIS

   PRAECIS PHARMACEUTICALS INCORPORATED is a biopharmaceutical
company focused on the discovery and development of novel compounds
that have the potential to address unmet medical needs or improve
existing therapies. PRAECIS has a novel MetAP-2 inhibitor, PPI-2458,
in clinical development for cancer indications, including
non-Hodgkin's lymphoma and solid tumors, as well as an innovative drug
discovery technology, DirectSelect(TM), which enables the generation
and practical use of ultra-large libraries for the discovery of orally
active compounds for drug development. PRAECIS has received approval
to market Plenaxis(R) in both the United States and Germany.

   This news release contains forward-looking statements, including
statements regarding the Company's plans for seeking partnerships
relating to, as well as the internal use of, its DirectSelect(TM)
technology. These statements are based on the Company's current
beliefs and expectations as to future outcomes and are not guarantees
of future events or performance. These statements are subject to
numerous risks, uncertainties and assumptions that could cause actual
events and results to differ from those anticipated or projected,
including, but not limited to, the Company's ability to continue
development of and successfully partner its DirectSelect(TM)
technology, as well as the risks set forth from time to time in the
Company's filings with the Securities and Exchange Commission,
including but not limited to the various risks discussed in the
Company's Annual Report on Form 10-K for the year ended December 31,
2005. The Company undertakes no obligation to update any
forward-looking statement made in this press release to reflect new
information, events or circumstances after the date of this release.