Arrowhead Research Appoints Dr. Mauro Ferrari to its Board of Directors

Arrowhead Research Corporation (NASDAQ: ARWR) today announced that Dr. Mauro Ferrari has joined the Company’s Board of Directors. Dr. Ferrari has served as Arrowhead’s Scientific Advisory Chairman since 2008 and is regarded as a thought leader and pioneer of nanomedicine. With his appointment to Arrowhead’s Board of Directors, Dr. Ferrari will resign his consultancy and his post on the Scientific Advisory Board of Arrowhead.

Dr. Ferrari is the president of the Alliance for NanoHealth, and he serves as Professor of Experimental Therapeutics at The University of Texas M.D. Anderson Cancer Center, and Professor of Bioengineering at Rice University. Dr. Ferrari has also been named President and CEO of The Methodist Hospital Research Institute (TMHRI), based in Houston, Texas.

Current member of the Arrowhead Board of Directors, LeRoy T. Rahn, has resigned to offer his seat on the Board to Dr. Ferrari.

Arrowhead’s Executive Chairman of the Board of Directors R. Bruce Stewart said, "Dr. Ferrari is a scientific visionary and has been a strong proponent of our efforts at Arrowhead. He brings a wealth of knowledge from his leadership roles at influential hospitals, academia and institutions to help us build-out our nanomedicine portfolio.

"On behalf of Arrowhead, I would also like to thank Lee for his dedication and contributions to our Company. We wish him well in his future endeavors,” concluded Mr. Stewart.

"Dr. Ferrari’s addition to Arrowhead’s Board is an important and powerful step for us as we become a focused nanomedicine company,” said Dr. Christopher Anzalone, Arrowhead President and CEO. "His deep technical expertise and new appointment at The Methodist Hospital Research Institute provide a unique and broad perspective that, we believe, will help us create value for our shareholders.”

Dr. Ferrari will begin his duties as President and CEO of TMHRI on September 1, 2010. The institute was established in 2004 to conduct translational research toward new diagnostics and therapies. It is home to more than 1,000 credentialed physicians, faculty and staff and more than 700 ongoing clinical trials. It expects to add to its existing 100,000 sq ft facility later this year when construction of a new 440,000 sq ft building is complete. The new building will house expanded interdisciplinary research, a Good Manufacturing Practice (GMP) facility to prepare clinical-grade biological agents and small molecules, state-of-the-art imaging equipment for preclinical and clinical studies, and a specialized laboratory for infectious disease research.

"I have no doubt that nanotechnology will revolutionize every aspect of medicine,” said Dr. Ferrari. "I believe Arrowhead is positioned perfectly to be the leader in the commercialization of nanotechnology-based products for medicine. I am honored to join this most distinguished Board of Directors, and help Arrowhead retain and expand its world-class leadership in the field.”

Dr. Ferrari is a fellow of the American Academy for the Advancement of Science (AAAS), American Institute for Medical and Biological Engineering, and the American Society of Mechanical Engineers. He has over 200 published works, over 30 issued patents, and is regularly invited to speak on biomedical nanotechnology and other topics worldwide.

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.

Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995:

This news release contains forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. These statements are based upon our current expectations and speak only as of the date hereof. Our actual results may differ materially and adversely from those expressed in any forward-looking statements as a result of various factors and uncertainties, including the future success of our clinical studies, our ability to successfully develop and manufacture products, rapid technological change in our industry, changes in demand for our future products, legislative, regulatory and competitive developments and general economic conditions. Our Annual Report on Form 10-K, and other SEC filings discuss these and other important risk factors that may affect our business, results of operations and financial condition. We undertake no obligation to revise or update publicly any forward-looking statements for any reason.