Insert Therapeutics, Inc. Unidym, Inc. Tego BioSciences, Inc. Calando Pharmaceuticals, Inc.
PRESS RELEASE
March 14, 2008

ARROWHEAD CEO PRESENTS 2008 OBJECTIVES

PASADENA, Calif. - March 14, 2008 - On March 14, 2008, Arrowhead Research Corporation’s (NASDAQ: ARWR) Chief Executive Officer, Christopher Anzalone, presented a slide show entitled “Creating Value by Building Nanobusiness from Nanoscience” following Arrowhead’s Annual Meeting of Stockholders. Dr. Anzalone began by describing the market opportunity presented by advances in nanoscience and Arrowhead’s key value drivers. He described the advantages of Arrowhead’s business model and his vision of the company as an as an institutional entrepreneur.

Dr. Anzalone briefly described each of Arrowhead’s subsidiaries, their opportunities and progress to date, as well as adjustments that are being made to streamline and make improvements at both the Arrowhead level and in the subsidiaries. Operational targets for 2008 were outlined for each of Arrowhead’s subsidiary companies, including investigator-led Phase II trials for Insert’s drug candidate, IT-101, an industry partnership for Calando’s siRNA delivery system, and various industry partnerships and outlicenses for Unidym.

Dr. Anzalone concluded the presentation by introducing Nanotope and Leonardo Biosystems, both portfolio companies co-founded by Dr. Anzalone and co-owned in party by The Benet Group, LLC. The Benet Group is owned by Dr. Anzalone, and the company expects to submit acquisition of The Benet Group for approval by Arrowhead stockholders in Spring 2008.

Dr. Mauro Ferrari, Director of Scientific Strategy of Arrowhead and co-founder of Leonardo Biosystems, a development stage drug delivery company, explained how the company is developing an advanced set of nanotechnology tools to deliver cancer therapeutics. Dr. Anzalone described Nanotope, a development stage regenerative medicine company that seeks to provide customized products to advance regeneration of specific tissues, including neuronal, vascular, bone, myocardial, and cartilage.

Dr. Anzalone’s presentation, followed by a question and answer period, was broadcast live via the Internet and by teleconference. A replay will be available for 90 days for those who were unable to attend the live broadcast. Information on how to access the webcast can be accessed on Arrowhead’s website at http://arrowres.com/meeting2008.html.

About Arrowhead Research Corporation

Arrowhead Research Corporation (www.arrowheadresearch.com) is a publicly-traded nanotechnology company commercializing new technologies in the areas of life sciences, electronics, and energy. Arrowhead is building value for shareholders through the progress of majority owned subsidiaries founded on nanotechnologies originally developed at universities. The company works closely with universities to source early stage deals and to generate rights to intellectual property covering promising new nanotechnologies. Currently, Arrowhead has five subsidiaries commercializing nanotech products and applications, including anti-cancer drugs, RNAi therapeutics, fullerene anti-oxidants, carbon-based electronics and compound semiconductor materials.

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 recent economic slowdown affecting technology companies, the future success of our scientific studies, our ability to successfully develop products, rapid technological change in our markets, changes in demand for our future products, legislative, regulatory and competitive developments and general economic conditions. Our Annual Report on Form 10-K and 10-K/A, recent and forthcoming Quarterly Reports on Form 10-Q and 10-Q/A, recent Current Reports on Forms 8-K and 8-K/A, our Registration Statement on Form S-3, and other SEC filings discuss some of the 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.

Contacts

Virginia Dadey; Vice President, Investor Relations
Telephone: 212.541.3707
Email: vdadey@arrowres.com