Merrimack Pharmaceuticals, Inc. is a biopharmaceutical company discovering, developing and preparing to commercialize medicines paired with companion diagnostics for the treatment of serious diseases, with an initial focus on cancer. The Company�s product candidates include MM-398, MM-121, MM-111, MM-302 and MM-151. The Company�s Network biology is an interdisciplinary approach to drug discovery and development that enables the Company to build functional and predictive computational models of biological systems based on quantitative, kinetic, multiplexed biological data. The Company provides its scientists with insights into how the complex molecular interactions that occur within cell signaling pathways, or networks, regulate cell decisions and how dysfunction within these networks leads to disease. As of June 31, 2011, the Company owned approximately 74% interest of Silver Creek.