About ARRY-797 / p38 InhibitorARRY-797 is an orally dosed p38-alpha kinase inhibitor discovered by Array scientists. p38 regulates PGE2 production, a significant pain mediator, and TNF and IL-1 production, both mediators of inflammation. Compared to other p38 inhibitors ARRY-797 has distinct properties; it is highly selective, has exceptional potency in whole blood, has a differentiated pharmacokinetic profile and is highly water soluble. ARRY-797 achieved statistically significant analgesic effects in two Phase 2 acute dental pain studies. ARRY-797 has been generally well-tolerated with over 450 subjects/patients treated. In these largely short duration studies, common adverse events included dizziness, headache, diarrhea and nausea, mostly mild in severity and with no clear relation to dose or duration of exposure. Array believes ARRY-797 has an opportunity to address a significant unmet medical need in both acute and chronic pain. About Array BioPharma: Array BioPharma Inc. is a biopharmaceutical company focused on the discovery, development and commercialization of targeted small-molecule drugs to treat patients afflicted with cancer and inflammatory diseases. Array has four core proprietary clinical programs: ARRY-614 for myelodysplastic syndromes, ARRY-520 for multiple myeloma, ARRY-797 for pain and ARRY-502 for asthma. In addition, Array has 10 partner-funded clinical programs including two MEK inhibitors in Phase 2 clinical trials: selumetinib with AstraZeneca and MEK162 with Novartis. For more information on Array, please go to www.arraybiopharma.com. Forward-Looking Statement This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including statements about the timing of completion or initiation of further trials involving ARRY-797, the potential for the results of ongoing clinical trials to support regulatory approval or the marketing success of ARRY-797, and future plans to progress, develop and partner ARRY-797. These statements involve significant risks and uncertainties, including those discussed in the most recent annual report filed on form 10-K, quarterly reports filed on Form 10-Q, and other reports filed by Array with the Securities and Exchange Commission. Because these statements reflect current expectations concerning future events, actual results could differ materially from those anticipated in these forward-looking statements as a result of many factors. These factors include, but are not limited to, the ability of Array to continue to fund and successfully progress research and development efforts with respect to ARRY-797; the ability of Array to out-license further development of ARRY-797 on terms that are favorable to Array; the willingness of pharmaceutical and biotechnology companies to in-license drugs for their product pipelines; risks associated with dependence on collaborators for the clinical development and commercialization of out-licensed drug candidates; the ability to effectively and timely conduct clinical trials in light of increasing costs and difficulties in locating appropriate trial sites and in enrolling patients who meet the criteria for certain clinical trials; and risks associated with dependence on third-party service providers to successfully conduct clinical trials within and outside the United States. Array is providing this information as of July 31, 2012 and undertakes no duty to update any forward-looking statements to reflect the occurrence of events or circumstances after the date of such statements or of anticipated or unanticipated events that alter any assumptions underlying such statements.