Arrowhead Assembles a Carbon Nanotube Patent Portfolio Through Exclusive Licenses with Leading Universities.

PASADENA, Calif. -- Arrowhead Research Corporation (Nasdaq: ARWR), a diversified nanotechnology company, announced today that wholly owned subsidiary NanoPolaris, Inc. has assembled a portfolio of intellectual property to facilitate and enable the manufacture of nanotube-based products. NanoPolaris has exclusively licensed U.S. patents and patent applications covering technologies developed at:

--California Institute of Technology

--Duke University

--The Pennsylvania State University 

--Rensselaer Polytechnic Institute

--Tsinghua University at Beijing

--University at Buffalo

--University of California, Los Angeles 

--University of Toronto

"We believe carbon nanotubes will create a manufacturing revolution comparable to what plastics did for materials and silicon did for electronics," said R. Bruce Stewart, Arrowhead's Chairman. "We are taking the lead in consolidating the fragmented patent landscape and working with manufacturers to integrate these materials into their end products."

It is widely believed that carbon nanotubes' unique electrical, mechanical and thermal properties can be harnessed to substantially improve a variety of products, including semiconductor devices, television displays, solar cells, health care products and materials used in everything from automobiles to baseball bats. Numerous companies are now seeking to develop scaled manufacturing techniques to incorporate nanotubes into their products.

"This portfolio of key patents and patent applications could be widely employed by different companies across many industries," said Leon Ekchian, President of Arrowhead. "NanoPolaris will not itself engage in manufacturing. Rather, it will provide a necessary and convenient patent toolbox to corporations planning to integrate nanotubes into their end products."

NanoPolaris will seek to generate revenue by licensing intellectual property to customers who will utilize nanotube technology in their products. NanoPolaris now controls commercialization of issued patents and patent applications claiming nanotube compositions of matter and general manufacturing techniques such as chemical vapor deposition synthesis, plasma chemical vapor deposition synthesis, purification, solubilization, separation of certain types of tubes, coating, functionalization and manipulation.

About Arrowhead Research Corporation

Arrowhead Research Corporation (www.arrowheadresearch.com) is a diversified nanotechnology company structured to commercialize products expected to have revolutionary impacts on a variety of industries, including materials, electronics, life sciences, and energy.

There are three strategic components to Arrowhead's business model:

--Outsourced R&D Program: Arrowhead identifies patented or patent-pending technologies at universities or government labs and funds additional development of those technologies in exchange for exclusive rights to commercialize the resulting prototypes. Leveraging the resources and infrastructure of these institutions provides Arrowhead with a highly cost-effective development pipeline. Currently, Arrowhead is supporting efforts in stem cell technology, and nanosensors at the California Institute of Technology and Stanford University.

--Commercialization Program: After prototypes have been sufficiently developed in the laboratories, Arrowhead forms or acquires majority-owned subsidiaries to commercialize the technology and provides the subsidiaries with strategic, managerial, and operational support. At present, Arrowhead owns majority interest in subsidiaries commercializing diverse technologies, including anti-cancer drugs, RNAi therapeutics, and compound semiconductor materials.

--The Patent Toolbox: Arrowhead has acquired or exclusively licensed patents and patent applications covering a broad range of nanotechnology. The Company is actively seeking to add to this intellectual property portfolio.

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.