LA JOLLA, California, November 17, 2003-Kalypsys, Inc., announced today a collaboration with CV Therapeutics, Inc. (Nasdaq: CVTX) to discover, develop and commercialize novel treatments for cardiovascular disease. The collaboration combines Kalypsys' proprietary lead discovery, medicinal chemistry and informatics technologies with CV Therapeutics' proven strengths in target validation, pre-clinical pharmacology and clinical development of cardiovascular drug candidates.

CV Therapeutics will contribute proprietary assays and lead compounds to initiate the collaboration. Kalypsys will develop high throughput screens, run them against its proprietary compound collection, and then use its medicinal chemistry and informatics capabilities to optimize CV Therapeutics' existing leads and new leads identified at Kalypsys. CV Therapeutics will later carry out pharmacological studies, pre-clinical development and human trials, as appropriate.

Under the terms of the agreement, Kalypsys will receive an upfront payment, research funding, equity investments and milestone payments, and it will have the option of co-funding and co-developing all drug candidates that result from the partnership. If Kalypsys has elected not to co-fund or has withdrawn its co-funding, Kalypsys also has the option to later opt back in to co-funding a program.

Dr. Louis Lange, Chief Executive Officer at CV Therapeutics said, "Kalypsys' highly efficient lead discovery and optimization capabilities should allow us to rapidly obtain top-priority lead compounds against our drug targets. We believe this collaboration will be a source of important new drug candidates which may improve the likelihood of clinical success."

"CV Therapeutics is an acknowledged leader in the development of potential new therapies for cardiovascular disease and has demonstrated great skill in moving drug candidates through the clinic," said Dr. Kevin Lustig, Kalypsys co-founder and Director, Lead Discovery. "We are thrilled to join with them to develop important new medicines for cardiovascular disease."

"We feel the most efficient route to creating a sustainable pipeline of drug candidates is through a combination of internal development and external collaborations, both of which we are actively pursuing," said Dr. John McKearn, Chief Scientific Officer at Kalypsys. "This partnership offers us a great opportunity to work in the cardiovascular arena with a proven leader and share ownership in the resulting commercial products."

About Kalypsys

Kalypsys is a biopharmaceutical company that uses advanced automation technologies to evaluate drug candidates in cellular models of disease and then optimize the safety and efficacy of select candidates. Through the use of its technology, Kalypsys is able to make better decisions earlier in the discovery process. Kalypsys is developing drug leads in multiple therapeutic areas including cancer, inflammation, metabolic diseases and cardiovascular disorders. In addition to carrying out drug discovery programs based on internal research, Kalypsys seeks to enhance partners' discovery programs through technology-transfer or collaborative relationships. Kalypsys completed a $43 million series A financing round in April of 2002, led by the Sprout Group, co-led by Tavistock Life Sciences and included CMEA Ventures, Lombard Odier Darier Hentsch & Cie, 5AM Ventures, Novartis Bioventure Fund, Aravis Ventures, Alejandro Zaffaroni and the Singapore E.D.B.

For more information on Kalypsys, please visit http://www.kalypsys.org For further information, please contact:

Pratik Shah, Ph.D. of Kalypsys, +1-858-754-3333; or
Liz Thompson, Ph.D. of Atkins + Associates, +1-858-527-3492