ENSEMBLE DISCOVERY AND ROCHE INITIATE RESEARCH COLLABORATION TO APPLY NEW DIAGNOSTIC TECHNOLOGY TO OPTIMIZE CANCER THERAPY Collaboration will enable analysis of critical drug target family in patient cancer biopsies and selection of appropriate therapy CAMBRIDGE, MA - (July 30, 2007) – Ensemble Discovery Corporation today announced the initiation of a collaboration with Roche of Basel, Switzerland to apply Ensemble’s proprietary diagnostic technology to the optimization of selection of cancer therapy. The collaboration will apply this technology (known as DNA-Programmed ChemistryTM) to analyze combinations of members of the Epidermal Growth Factor Receptor (EGFR) family that are present in cancer tissues. The goal of the collaborative project is to create a sensitive test to detect receptor dimers in human cancer tissue samples. The potential clinical benefit of the test is to select cancer patients who are most likely to respond to a particular therapy targeted against a member of the EGFR family. The particular combinations of EGFR dimers present in the cancer are believed to be a significant factor in determining the efficacy of drugs targeting the EGFR family. The Ensemble test will correlate the EGFR family dimer pattern with efficacy of particular anti-cancer drugs in order to improve therapy selection based on an individual’s molecular constitution. The EGFR family includes some of the most widely targeted molecules in modern cancer medicine. There are six drugs against this family on the market and several more in clinical trials. However, in each case, the drugs show activity in a subset of the patients in which they are currently indicated and the mechanisms of this partial efficacy are not well understood. Ensemble’s test will be initially used to monitor breast cancer patients but could also have utility in other solid tumors such as colon and lung cancer. “We are very pleased to enter into this collaboration with Roche,” said David J. Livingston, Ph.D., Senior Vice President, and head of the biodetection program at Ensemble Discovery. “The opportunity to collaborate with a global leader in both pharmaceuticals and diagnostics as well as pioneering anti-EGFR therapies, offers a unique opportunity to apply the collective expertise and experience for the development of our tests in cancer diagnosis.” “Roche is one of the world’s leading cancer companies with commitment to both the drug and diagnostic sides of cancer healthcare,” said Laurence Reid, Chief Business Officer of Ensemble Discovery. “Ensemble is committed to deploying its DNAProgrammed Chemistry technology for the development of diagnostic tests that will enable the optimal use of the important anti-EGFR family of drugs in cancer patients.” Ensemble is developing a suite of diagnostic services and kits, based on DPCTM, to analyze EGFR family dimers and other cancer markers for use in cancer diagnosis and drug selection. The company will partner with leading pharmaceutical and diagnostic companies to deliver its diagnostic products and position them relative to ongoing drug development. About Ensemble Discovery Corporation Based in Cambridge, MA, Ensemble Discovery Corporation is harnessing a fundamentally new approach to controlling chemical reactivity to develop novel classes of therapeutics and bioassays. Ensemble Discovery is deploying DNA-Programmed Chemistry (DPC), which is based on the groundbreaking work of Professor David Liu of Harvard University and Howard Hughes Medical Institute. In its drug discovery programs, Ensemble uses DPC to generate Programmed MacrocyclesTM as drug candidates for pharmaceutically challenging targets. In its diagnostic programs, Ensemble uses DPC to control the generation of detection signals in response to the presence of specific molecular events underlying human diseases. DPC-based assays are particularly adept at the detection of dimeric molecules such as growth factor receptors on cell surfaces. About the EGFR Family The Epidermal Growth Factory Receptor (EGFR) family is one of the best characterized families of cancer-associated proteins. Members of the family are known to be involved in the etiology of breast, lung and colon cancer and their pathologic and biochemical mechanisms have been widely studied since their discovery and isolation in the 1980s.