Arrowhead's New Nanobioscience Subsidiary Plans Preclinical Studies and Collaboration with NCI.

PASADENA, Calif. -- Arrowhead Research Corporation (NASDAQ:ARWR) announced today that its new wholly-owned nanobioscience subsidiary has changed its name from "C Sixty Acquisition Corp." to "Tego BioSciences Corporation." The subsidiary recently acquired the assets of C Sixty, Inc. and is focused on the development of new protective products based on the anti-oxidant properties of modified buckministerfullerenes (also known as fullerenes or buckyballs). Tego is initially developing products to reduce oxidative damage caused by sun exposure, radiation therapy, and chemotherapy and mitigate complications associated with organ transplantation and tissue engineering.

"Tego is set to commence preclinical animal studies in collaboration with the National Cancer Institute this summer," said R. Bruce Stewart, Chairman of Arrowhead. "Tego is in the process of assembling a business and technical team with expertise in nanoparticle-based therapeutics and skin care products."

The preclinical studies will be performed in the NCI's Nanotechnology Characterization Lab (NCL) to measure the ability of a Tego fullerene formulation to protect against harmful side effects of two anti-cancer drugs, cisplastin and adriamycin. The first stage of the studies will use NCL's resources, with follow on funding from Tego, as appropriate.

The National Cancer Institute (NCI), working in concert with the National Institute of Standards and Technology (NIST) and the U.S. Food and Drug Administration (FDA), established the Nanotechnology Characterization Laboratory (ncl.cancer.gov) to perform preclinical efficacy and toxicity testing of nanoparticles. The NCL serves as a national resource and knowledge base for all cancer researchers to facilitate the regulatory review of nanotechnologies intended for cancer therapies and diagnostics. By providing the critical infrastructure and characterization services to nanomaterial providers, the NCL can accelerate the transition of basic nanoscale particles and devices into clinical applications, thereby reducing suffering and death from cancer.

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, carbon-based electronics and compound semiconductor materials.

About Tego BioSciences Corporation

Tego BioSciences Corporation (www.tegobio.com) is developing and commercializing therapeutics and other products based on the antioxidant properties of modified fullerenes. The patent protected platform forms the basis for several products. The company is initially focused on developing products to reduce oxidative damage caused by sun exposure, radiation therapy, and chemotherapy and mitigate complications associated with organ transplantation and tissue engineering. For other applications of derivatized fullerenes such as MRI imaging or central nervous system disorders, Tego BioSciences will establish a program to license and partner the commercialization of its intellectual property to third parties.

Fullerenes are a highly structured, nanoscale form of carbon, similar to carbon nanotubes. Roughly one nanometer in diameter, the molecules are composed of 60 carbon atoms and have the symmetry of soccer balls. The spherical shape, hollow interior, and 60 carbon atoms of the molecule allow drug designers the opportunity to attach therapeutic and targeting chemical groups in many configurations.

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