UK-based AstraZeneca and Array BioPharma, headquartered in Colorado, have selected a third compound for their small molecule MEK anticancer program, the companies have reported. This triggered a $1 million milestone payment from AstraZeneca to Array. The second compound was selected in January 2006, which also paid a $1 million milestone to Array. In December 2003, Array partnered the oncology portion of its MEK program, including its lead compound, ARRY-142886, for co-development and commercialization with AstraZeneca. At that time, Array and AstraZeneca partnered to research and develop additional clinical candidates.
MEK is an enzyme at the intersection of several biological pathways, which regulates cell proliferation and survival as part of the Ras/Raf/MEK/ERK pathway. Constitutive activation of the Ras/Raf/MEK/ERK pathway has been implicated in many cancers, including lung, pancreatic, colon, melanoma and thyroid caused by cancer-associated, mutational activation of bRAF and Ras proteins.