Arrowhead Research Corporation (NASDAQ: ARWR) today announced that it intends to offer units consisting of shares of common stock and warrants in a public offering. Dawson James Securities, Inc. will serve as the sole book-running manager for the offering. While the offering is expected to price before 9:30 am EST on January 25, 2013, the offering is subject to market conditions, and there can be no assurance as to whether or when the offering may be completed, or as to the actual size or terms of the offering. A registration statement relating to the shares of common stock and warrants issued in the offering, and the shares of common stock issuable upon exercise of the warrants issued in the offering, has been filed with, and declared effective by, the Securities and Exchange Commission (the “SEC”). A preliminary prospectus supplement, as well as a final prospectus supplement, relating to the offering will be filed with the SEC, each of which will form a part of the effective registration statement. When available, copies of the preliminary and final prospectus supplements relating to these securities may be obtained by visiting the SEC’s website at www.sec.gov or from Dawson James Securities, Inc., 925 South Federal Highway, 6th Floor, Boca Raton, FL 33432 or via telephone at (866) 928-0928. This press release shall not constitute an offer to sell or the solicitation of an offer to buy these securities, nor shall there be any sale of these securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of any such jurisdiction. About Arrowhead Research Corporation Arrowhead Research Corporation is a clinical stage targeted therapeutics company with development programs in oncology, obesity, and chronic hepatitis B virus infection. The company is leveraging its platform technologies to design and develop peptide-drug conjugates (PDCs) which specifically home to cell types of interest while sparing off-target tissues, create targeted drugs based on the gene silencing RNA interference (RNAi) mechanism, and work with partners to create improved versions of traditional small molecule drugs.