Merrimack Pharmaceuticals, Inc., incorporated in 1993, 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 Companys product candidates include MM-398, MM-121, MM-111, MM-302 and MM-151. As of June 31, 2011, the Company owned approximately 74% interest of Silver Creek.
The Companys 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. The Company applies network biology throughout the research and development process, including for target identification, lead compound design and optimization, diagnostic discovery, in vitro and in vivo predictive development and the design of clinical trial protocols.
MM-398
MM-398 is a stable nanotherapeutic encapsulation, or enclosed sphere carrying an active drug, of the marketed chemotherapy drug irinotecan. MM-398 achieved its primary efficacy endpoints in Phase 2 clinical trials in pancreatic and gastric cancer. In an open label, single arm Phase 2 clinical trial of MM-398 as a monotherapy in 40 metastatic pancreatic cancer patients who had previously failed treatment with gemcitabine, patients treated with MM-398 achieved median overall survival of 22.4 weeks. Additionally, 20% of the patients in this Phase 2 trial survived for more than one year, and the Company observed a disease control rate, meaning patients exhibited stable disease or partial or complete response to treatment, of 47.5% at six weeks.
The Company focuses on initiating a Phase 3 clinical trial of MM-398 for the treatment of patients with metastatic pancreatic cancer who have previously failed treatment with gemcitabine. The trial is expected to enroll approximately 250 patients and is designed to compare the efficacy of MM-398 as a monotherapy against the combination of the chemotherapy drugs fluorouracil, or 5-FU, and leucovorin. There are multiple ongoing Phase 1 and Phase 2 clinical trials of MM-398. In July 2011, the United States Food and Drug Administration (FDA) granted MM-398 orphan drug designation for the treatment of pancreatic cancer.
MM-121
MM-121 is a fully human monoclonal antibody that targets ErbB3, a cell surface receptor, or protein attached to the cell membrane that mediates communication inside and outside the cell, that the Companys network biology approach identified as a target in a range of cancers. A monoclonal antibody is a type of protein normally produced by cells of the immune system that binds to just one epitope, or chemical structure, on a protein or other structure. MM-121 is designed to inhibit cancer growth directly, restore sensitivity to drugs to which a tumor has become resistant and delay the development of resistance of a tumor to other agents. In collaboration with Sanofi, the Company focuses on testing MM-121 in combination with both chemotherapies and other targeted agents across a range of spectrum of solid tumors, including lung, breast and ovarian cancers. The Company partnered MM-121 with Sanofi after it initiated Phase 1 clinical development of the product candidate.
MM-111
MM-111 is a bispecific antibody designed to target cancer cells that are characterized by overexpression of the ErbB2 cell surface receptor, also referred to as HER2. A bispecific antibody is a type of antibody that is able to bind simultaneously to two distinct proteins or epitopes. The Companys network biology approach identified that ligand-induced signaling through the complex of ErbB2 (HER2) and ErbB3 is a promoter of tumor growth and survival than previously appreciated.
MM-302
MM-302 is a nanotherapeutic encapsulation of doxorubicin with attached antibodies that are designed to target MM-302 to cells that over express the ErbB2 (HER2) receptor. The Company is conducting a Phase 1 clinical trial of MM-302 in patients with advanced ErbB2 (HER2) positive breast cancer.
MM-151
MM-151 is an oligoclonal therapeutic consisting of a mixture of three fully human monoclonal antibodies designed to bind to non-overlapping epitopes of the epidermal growth factor receptor (EGFR). EGFR is also known as ErbB1. An oligoclonal therapeutic is a mixture of two or more distinct monoclonal antibodies. The Company has designed MM-151 to block signal amplification that occurs within the ErbB cell signaling network. The Company has submitted an investigational new drug application (IND), to the FDA for MM-151 in July 2011.
