Evotec OAI and Rigel Pharmaceuticals Enter Into Medicinal Chemistry Agreement To Identify A New Class of Anti-Cancer Compounds Called Ubiquitin Ligase Inhibitors

South San Francisco, California/ Hamburg, Germany/ Abingdon, UK - Evotec OAI AG, Hamburg, Germany (Neuer Markt: EVT), a supplier of integrated high-value added drug discovery services, and Rigel Pharmaceuticals Inc., a drug discovery and development company (Nasdaq: RIGL), announced today the signing of a medicinal chemistry agreement for the optimisation of small molecules focused on inhibitors of ubiquitin ligases. Ubiquitin ligases are involved in cell division and the progression of certain cancers. Research on this target class is an important new area in the field of oncology.  Rigel is a leader in the field of ubiquitin ligases and their applications in oncologic, inflammatory and viral diseases.
Under the terms of the agreement, Evotec OAI will use their leading-edge integrated drug discovery platform to select and synthesise lead compounds with optimised properties for Rigel to screen against their target proteins, and to identify novel scaffolds from Evotec OAI's portfolio of validated chemistries, with the aim of identifying an IND candidate in 12 months. Initially, Evotec OAI's molecular modelling expertise and computational platform will be used to perform SAR (structure activity relationship) analysis including pharmacophore modelling and in silico docking studies on selected Rigel small molecule drug leads. These proprietary compounds have been identified as most active in Rigel's anti-cancer programme on ubiquitin ligases. This information will be used to select and synthesise the additional lead compounds.
Additionally, Evotec OAI will use their computational chemistry expertise to analyse Rigel's corporate library and to identify additional scaffolds to increase the overall diversity of the library whilst retaining the drug and lead-like properties. Through the agreement, Rigel will also gain access to Evotec OAI's lead discovery library for screening against the ligase and additional Rigel targets.
Rigel will  provide funding to Evotec OAI for services conducted during this programme. In addition, Evotec OAI may receive future milestone payments if discovery projects meet defined goals and products are commercialised.
"We look forward to building a partnership with Rigel in their very exciting area of ubiquitin ligase research," said Mario Polywka, Chief Operating Officer of Evotec OAI. "Using our world class drug discovery platform will enable us to assist Rigel in accelerating their drug discovery programme."
"Rigel has built a very strong capability in ubiquitin ligase research and drug development, including the design of numerous biochemical and cellular assays to analyze the biology and proteomics of ligases, a robust and efficient high throughput screening program, a focused chemistry program with promising initial chemical hits and an experienced preclinical oncology development team," said James M. Gower, Rigel's President and Chief Executive Officer.  "This collaboration marks our second this month in the area of ubiquitin ligases, and  Evotec's expertise in computational and medicinal chemistry will contribute greatly to our ability to rapidly identify a clinical candidate in this promising new area of research."
About Evotec OAI
Evotec OAI offers the full range of high-value added products and services required to discover and develop drugs more effectively and efficiently.  By integrating accelerated methods in biology, chemistry and screening, the Company has established a unique position as a one-stop-shop for all the critical elements in the drug discovery research and development process from target to clinical development. Approximately 540 people are based in Hamburg, Germany and Abingdon, U.K.  Evotec OAI already has close links with many of the leading companies in the pharmaceutical and biotechnology industries including Novartis, Pfizer,
GlaxoSmithKline, Aventis, Pharmacia/Sugen, Eli Lilly, Bayer, BMS, Roche, Amgen, Biogen, Vertex, Serono and Immunex.  The Company's shares are listed on the Neuer Markt of the Frankfurt Stock Exchange.
About Rigel Pharmaceuticals
Rigel Pharmaceuticals ( www.rigel.com ) is a drug discovery and development company that uses advanced functional genomics tools to discover novel drug targets. Rigel's technology is designed to identify molecules which play an important role in regulating a human cell's response to disease by testing a very large number of proteins in a very large number of cells to determine which proteins will change the cell's response to the disease. Rigel currently has programs in asthma/allergy, autoimmunity, transplant rejection, rheumatoid arthritis, inflammatory bowel disease, chronic bronchitis, cancerous tumor growth and hepatitis C. Rigel has multi-year collaborations with Pfizer Inc., Cell Genesys, Inc., Janssen Pharmaceutica N.V. and Novartis Pharma A.G. Rigel is based in South San Francisco, California.
Contact Rigel Pharmaceuticals Inc.:
Audra Nass
Phone: 001 650 624 1246
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In addition to any historical information presented herein, this release contains forward-looking statements regarding the future activities of Rigel within the meaning of the Private Securities Litigation Reform Act of 1995 and such statements involve a high degree of risk and uncertainty.  Many possible factors could affect future results and performance of Rigel's services and technologies such that actual results and performance may differ materially.  If Rigel's services and technologies fail to perform as expected or if there is lower demand for these than expected, the financial condition and operating results of the company may be materially and adversely affected.  Rigel's financial condition and operating results may also be materially and adversely affected by a number of other factors, including, but not limited to, adverse changes in competitive and economic conditions, or difficulties and adverse actions by third parties and licensors, as well as other risks identified in Rigel's Annual Report on Form 10-K for the year ended December 31, 2000 and subsequent filings made with the Securities and Exchange Commission from time to time.  The information in this press release is current as of its release date and Rigel does not intend to update the forward-looking information contained herein.