Arrowhead Options Obesity-Fighting Technology from MD Anderson Cancer Center

Arrowhead Research Corporation (NASDAQ: ARWR) today announced that it has signed an option agreement with The University of Texas MD Anderson Cancer Center to negotiate a license in a defined field to a class of compounds that is believed to kill fat tissue by specifically targeting the blood vessels that supply it. The technology was developed in the laboratory of Drs. Renata Pasqualini and Wadih Arap at MD Anderson in Houston, Texas. Arrowhead sees the technology platform as an attractive candidate around which to form a new majority-owned subsidiary to steer the technology through clinical development.

"We’ve been tracking obesity and metabolic markets for some time and have been searching for technology with the potential of serving these markets in a unique and powerful way,” said Christopher Anzalone, Arrowhead’s CEO. "We believe the platform that Drs. Pasqualini and Arap have developed may represent a great leap forward in treating obesity, a condition with significant quality of life issues and virtually unparalleled direct and indirect economic costs. This is also a relatively advanced program from a development standpoint and could be ready to begin human clinical trials in the near term.”

The breakthrough approach was first published in the prestigious scientific journal Nature Medicine in May 2004 and received widespread media attention, including write-ups in the Wall Street Journal and the New York Times. Since 2004, Drs. Pasqualini and Arap have worked to refine the technology and complete preclinical efficacy and toxicity testing in preparation for clinical trials.

About Arrowhead Research Corporation

Arrowhead Research Corporation (www.arrowheadresearch.com) (NASDAQ: ARWR) is a nanotechnology company commercializing new technologies in the areas of life sciences and electronics. Arrowhead is seeking to build value for shareholders through the progress of its portfolio companies. Currently, Arrowhead is focused primarily on its two majority owned subsidiaries, Unidym, a leader in carbon nanotube technology for electronic applications, and Calando, at the forefront of clinical application of RNAi delivery technology. Arrowhead also has minority investments in two privately held nanobiotech companies.

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