Arrowhead (ARWR) Announces the Appointment of Nobel Laureate Dr. Leland Hartwell

Apr. 7, 2010 (Business Wire) — Arrowhead Research Corporation (Nasdaq:ARWR) announced today the appointment of Dr. Lee Hartwell to its Scientific Advisory Board. Dr. Hartwell is a well-known expert in cancer biology and was awarded the Nobel Prize in Medicine in 2001 for his ground-breaking work in cell cycle regulation. Dr. Hartwell is President of the Fred Hutchinson Cancer Research Center in Seattle, Washington. His insights into cell cycle control are being used at the Hutchinson Center and elsewhere to develop treatments for cancer and other diseases.

“Dr. Hartwell is one of the great scientific thought leaders of our time, and we are honored to have him as part of our team,” said Arrowhead President and CEO, Dr. Christopher Anzalone. “He will play a large role helping to focus our strategy and extend our scientific reach as we look forward to new opportunities and initiatives.”

“I am committed to improving patient outcomes and reducing healthcare costs through improved molecular diagnostics,” said Dr. Hartwell. “Arrowhead has the potential to bring together the technologies that can implement molecular diagnostics at the point of care and it is an exciting opportunity for me to participate in that vision.”

Dr. Hartwell joins Drs. Chad Mirkin, Mauro Ferrari, and Tom Tombrello on Arrowhead’s Scientific Advisory Board. These are some of the world’s most prolific pioneers in nanotechnology and medicine, and they are tasked with helping to develop a dynamic scientific roadmap to guide Arrowhead’s CEO in establishing the Company as the preeminent outlet for commercializing revolutionary advances in the field. The Scientific Advisory Board provides broad scientific direction for the Company, as well as very specific recommendations with respect to technologies that could serve as the basis for new companies, technologies that could augment the scientific and market positions of existing subsidiaries, and recruiting world-class personnel for Arrowhead and its subsidiaries. In addition, these thought leaders have deep relationships within academia and industry, and will be critically involved in establishing partnerships for Arrowhead and its subsidiaries.

Dr. Hartwell is involved in national and international projects to increase the number of laboratories working in protein diagnostics, develop more team science, improve the availability of informatics for data sharing, provide standardized reagents and stimulate new technology development. Dr. Hartwell is the recipient of many national and international scientific awards. His honors include the Albert Lasker Basic Medical Research Award, the Gairdner Foundation International Award and the Alfred P. Sloan Award in cancer research. He is a member of the National Academy of Sciences. He earned his B.S. at the California Institute of Technology and his Ph.D. from the Massachusetts Institute of Technology. He joined the University of Washington faculty in 1968 and has been a genetics professor there since 1973. In 1996, he joined the faculty of Seattle’s Fred Hutchinson Cancer Research Center and, in 1997, became its president and director.

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 subsidiaries and investments. 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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