Stephen Hill, ArQule President and CEO, to Join Solvay Pharmaceuticals, Inc. as New President and CEO

Dr. Stephen A. Hill, president and chief executive officer of ArQule, Inc. (NASDAQ: ARQL), has been appointed the new president and chief executive officer of Solvay Pharmaceuticals, Inc. (U.S.), as announced today by Solvay. Dr. Hill will join Solvay on April 1, 2008. This appointment follows ArQule’s announcement on January 7, 2008 that it has initiated a search for a successor to Dr. Hill, who previously communicated to the board of directors of ArQule his intention to leave the Company. Peter S. Lawrence, who was recently appointed to the position of chief operating officer at ArQule, has taken operational responsibility for leadership of the Company. Dr. Hill will remain in his position through the end of March. "Today’s statement by Solvay has provided the opportunity to add clarity to our previous announcement of Steve Hill’s departure from ArQule after nine years, culminating in an effective transition from a combinatorial chemistry company to an oncology-focused research and development company,” said Mr. Lawrence. "The management transition at ArQule is proceeding smoothly with no impact on our clinical programs and other operations.” "Although we will miss Steve Hill’s contributions to ArQule, we understand the opportunity presented by a leadership role in a global pharmaceutical company with well developed sales and commercialization capabilities, and we wish him well in this new endeavor,” said Patrick J. Zenner, chairman of ArQule’s board of directors. About ArQule ArQule is a biotechnology company engaged in the research and development of next-generation, small-molecule cancer therapeutics. The Company's targeted, broad-spectrum products and research programs are focused on key biological processes that are central to cancer. ArQule's lead clinical-stage products have been generated from two scientific platforms: Cancer Survival Protein modulation and Activated Checkpoint Therapy(R) (ACT). The Cancer Survival Protein modulation platform has generated a clinical-stage product that mediates its effects by inhibiting the activity of a molecule known as c-Met, which plays multiple roles in cancer cell growth, survival, invasion, angiogenesis and metastasis. The ACT platform is designed to kill cancer cells selectively while sparing normal cells through direct activation of DNA damage response/checkpoint pathways. The Company's lead ACT program, based on the E2F-1 pathway, is partnered with Hoffman-La Roche. For more information, please visit www.arqule.com. This press release contains forward-looking statements regarding the Company’s clinical-stage products and its discovery of new product candidates. These statements are based on the Company’s current beliefs and expectations, and are subject to risks and uncertainties that could cause actual results to differ materially. Positive information about early stage clinical trial results does not ensure that later stage or larger scale clinical trials will be successful. The results achieved in later stage trials may not be sufficient to meet applicable regulatory standards. Problems or delays may arise during clinical trials or pre-clinical development or in the course of developing, testing or manufacturing these compounds that could lead the Company or its partner to discontinue development. Even if later stage clinical trials are successful, the risk exists that unexpected concerns may arise from analysis of data or from additional data or that obstacles may arise or issues be identified in connection with review of clinical data with regulatory authorities or that regulatory authorities may disagree with the Company’s view of the data or require additional data or information or additional studies. In addition, the planned timing of initiation and completion of clinical trials, as well as the planned timing and initiation of pre-clinical activities, are subject to the ability of the Company to enroll patients, enter into agreements with clinical trial sites and investigators, and resolve other technical hurdles and issues. The Company may also not be able to fund and to successfully advance internal research activities and to progress pre-clinical compounds into clinical development. Drug development involves a high degree of risk. Only a small number of research and development programs result in the commercialization of a product. Furthermore, ArQule may not have the financial or human resources to successfully pursue drug discovery in the future. For more detailed information on the risks and uncertainties associated with the Company’s drug development and other activities see the Company’s periodic reports filed with the Securities and Exchange Commission. The Company does not undertake any obligation to publicly update any forward-looking statements.