Antibody Targets Endosialin, a Protein Widely Expressed on Tumors and Tumor Blood Vessel Cells

EXTON, PA, USA | June 9, 2009 | Morphotek®, Inc., a subsidiary of Eisai Corporation of North America, announced that the U.S. Food and Drug Administration (FDA) cleared its investigational new drug (IND) application to study MORAb-004 in the treatment of patients with solid tumors. MORAb-004 targets endosialin, a protein expressed on cells associated with tumors and tumor blood vessel cells. The IND became effective 30 days after its initial submission to the FDA by Morphotek.

Some researchers have demonstrated that endosialin, the target of MORAb-004, is necessary for the development of new blood vessels (a process called angiogenesis). New blood vessels are required to provide blood flow to tumors for growth. Endosialin is expressed on pericytes which are cells that surround the smallest blood vessels and are needed for the survival, migration and differentiation of small blood vessels.

"The mechanism of action of MORAb-004, the concept of disturbing the tumor environment, is novel in cancer therapy," said Martin D. Phillips, M.D., Morphotek’s Chief Medical Officer. "We are pleased to be carrying out the Phase I study with one of the world’s leading health care institutions to focus on treating solid tumors and continue clinical development of this potential new treatment."

MORAb-004, which targets the growth of endosialin-expressing cells in tumor blood vessels, will be used to treat patients with solid tumors. Other anti-angiogenesis drugs target tumor endothelial cells, rather than pericytes. Treatment with MORAb-004 offers an alternative means to suppress tumor angiogenesis and growth.

"MORAb-004 is another unique therapeutic antibody being developed by our company that is believed to inhibit tumor growth via a disease-associated pathway identified and studied by one of our collaborative partners," said Nicholas Nicolaides, President and CEO of Morphotek. "Targeting of pericytes is a novel strategy in the anti-angiogenesis field and we look forward to reporting the results of these studies."

Morphotek obtained exclusive rights to develop and commercialize this antibody worldwide from the Ludwig Institute for Cancer Research (LICR). The endosialin protein as well as a precursor monoclonal antibody specific for endosialin, which is related to MORAb-004, were discovered in Dr. Lloyd Old’s laboratory at LICR.

About Morphotek

Morphotek®, Inc., a subsidiary of Eisai Corporation of North America, is a biopharmaceutical company specializing in the development of protein and antibody products through the use of novel and proprietary technologies. These technologies have been successfully applied to a variety of molecules that are suitable for pharmaceutical product development in the areas of antibody therapeutics, protein therapeutics, product manufacturing, drug target discovery, and improved output traits for commercial applications. The company is currently focusing its platform on the development and manufacturing of therapeutic antibodies for the treatment of cancer, inflammation and infectious disease. For more information, please visit www.morphotek.com.

About Eisai Corporation of North America

Eisai Corporation of North America is a wholly-owned subsidiary of Eisai Co., Ltd., a research-based human health care (hhc) company that discovers, develops and markets products throughout the world. Eisai focuses its efforts in three therapeutic areas: neurology, gastrointestinal disorders and oncology/critical care. Eisai Corporation of North America supports the activities of its operating companies in North America, which include: Eisai Research Institute of Boston, Inc., a discovery operation with strong organic chemistry capabilities; Morphotek, Inc., a biopharmaceutical company specializing in the development of therapeutic monoclonal antibodies; Eisai Medical Research Inc., a clinical development group; Eisai Inc., a commercial operation with manufacturing and marketing/sales functions; and Eisai Machinery U.S.A., which markets and maintains pharmaceutical manufacturing machinery. For more information about Eisai, please visit www.eisai.com.

SOURCE: Eisai