Arrowhead to Present at Master Investor 2013

PASADENA, Calif. — April 24, 2013 — Arrowhead Research Corporation (NASDAQ: ARWR), a targeted therapeutics company, today announced that its President and CEO, Dr. Chris Anzalone, will present at Master Investor, the UK’s leading investment show, on Saturday, April 27 at 2:05 p.m. BST at the Business Design Centre in London. Details can be found on the event website at http://masterinvestor.co.uk/.

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) that 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.

For more information please visit http://www.arrowheadresearch.com, or follow us on Twitter @ArrowRes. To be added to the Company’s email list to receive news directly, please send an email to ir@arrowres.com