Item 1.01. Entry into a Material Definitive Agreement. On June 17, 2009, Array BioPharma Inc. (the "Company") entered into a First Amendment to Drug Discovery and Development Agreement with Celgene Corporation ("Celgene"). The amendment amended certain provisions of the Drug Discovery and Development Agreement entered into by the Company and Celgene as of September 21, 2007 (the "Agreement") relating to the discovery, development and commercialization of novel therapeutics in cancer and inflammation. The amendment substitutes a new discovery target for an existing target that will be removed from the Agreement. The Company will continue to have responsibility for the discovery and clinical development of compounds that may be directed at the substitute target through Phase 1 or 2a trials, and the substituted target will be subject to Celgene's existing option to select two of any of four targets at any time until the earlier of completion of Phase 1 or Phase 2a trials for the drug directed at the target and seven years after the start of the collaboration on that target. In consideration for amending the Agreement, Celgene has agreed to pay the Company an up-front fee of $4.5 million within 15 days of the date of the amendment. The amendment also provides for an enhanced milestone payment relating to the selection of a compound directed at the substituted target if certain conditions are met and amends the milestone payments payable to the Company for achievement of development goals for drugs directed at the substituted target following certain changes in control of the Company.