
| April 27, 2007 |

Kyowa Hakko in-licenses ARQ 197, |

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On April 27, 2007, Kyowa Hakko Kogyo Co., Ltd. based in Tokyo, Japan (President and CEO: Dr. Yuzuru Matsuda) entered into a license agreement with the US drug development company ArQule based in Massachusetts, US (President and CEO: Dr. Stephen A. Hill), whereby Kyowa Hakko will be granted the exclusive right to develop and market the anticancer agent ARQ 197 for the treatment of solid tumors in Japan and some other Asian regions (China, South Korea, and Taiwan). Having completed phase I studies in the US, ArQule is now making preparations for starting the next phase of clinical development of ARQ 197. Under this agreement, Kyowa Hakko will carry out the clinical program of ARQ 197 for its registration and commercialization in Japan. ArQule will receive from Kyowa Hakko an upfront payment of 30 million dollars, milestone payments and royalties at various stages of development and product sales. ARQ 197 is a molecularly targeted compound that exerts anticancer activity by inhibiting a receptor tyrosine kinase known as c-Met. This small molecule anticancer agent can be administered orally. c-Met, which acts as a receptor for hepatocyte growth factor (HGF) / scatter factor (SF), is known to regulate a variety of physiological processes such as cell proliferation and survival. It has been shown that c-Met is activated in many types of malignancies, particularly in gastrointestinal cancers including stomach cancer, and plays roles in the aberrant growth, metastasis and other characteristics of cancer cells. ARQ 197 selectively inhibits c-Met, thereby blocking these features specific to cancer cells which leads to the anticancer activities. The phase I studies conducted in the US have demonstrated that ARQ 197 is safe with no serious side effects, and shows signs of anti-tumor activity in cancer patients with different types of solid tumors. These encouraging results warrant further clinical investigation of ARQ 197, which has the potential to provide therapeutic benefit as a novel anticancer drug with a favorable safety profile. Kyowa Hakko is making an extensive contribution to the treatment of cancer through the marketing of a number of anticancer drugs: Mitomycin, 5-FU, Navelbine®, Adriacin®, Farmorubicin®, Leunase®, Hysron®-H, Dacarbazine, and Platosin®. Its commitment to this field is also demonstrated in several products used to support cancer management: Neu-up®, Leukoprol®, Navoban®, and Durotep®, a narcotic skin patch for the relief of cancer pain. About ArQule ArQule, Inc. 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 designed to affect 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® (ACT). The Cancer Survival Protein modulation platform has generated a clinical-stage product designed to inhibit 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 Roche. For more information, please visit www.arqule.com. |