ArQule Announces Receipt of Milestone Payment from Wyeth.

WOBURN, Mass. -- ArQule, Inc. (NASDAQ: ARQL) today announced the receipt of a milestone payment from Wyeth (NYSE:WYE) in connection with the filing of an Investigational New Drug (IND) application by Wyeth to the U.S. Food and Drug Administration (FDA) related to a compound under development for Alzheimer's disease.

In connection with its former chemistry services business, ArQule has agreements with pharmaceutical collaborators such as Wyeth. Certain of the agreements include provisions for milestone and royalty payments in the event of development and commercialization of drugs derived from compounds provided to them by ArQule. ArQule has retained and is leveraging certain core chemistry capabilities developed and validated in the course of these collaborations to support its mission as an oncology company whose partners include Kyowa Hakko Kogyo Co., Ltd. and Hoffman-La Roche.

About ArQule

ArQule is a biotechnology company engaged in the research and development of next-generation, small-molecule cancer therapeutics. The Company's research programs are focused on the development of compounds that target key biological processes central to cancer. ArQule's lead products, which are in clinical-stage development, consist of ARQ 197, an inhibitor of the c-Met receptor tyrosine kinase, and ARQ 501 and ARQ 171, activators of the cell's DNA damage response mechanism mediated by the E2F-1 transcription factor. The Company's most advanced pre-clinical development programs are focused on the inhibition of the Eg5 kinesin motor protein and the B-RAF kinase. ArQule's discovery efforts include the identification of a new class of highly specific kinase inhibitors with a novel mechanism of inhibition.

This press release contains forward-looking statements regarding the Company's previous chemistry services collaborations, its 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 partners 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.