Nanotechnology Now - Press Release: Arrowhead subsidiary, Calando Pharmaceuticals publishes study on targeted systemic delivery of of siRNA

Home > Press > Arrowhead subsidiary, Calando Pharmaceuticals publishes study on targeted systemic delivery of of siRNA

Abstract:
Non-Human Primate Study First to Use Multiple, Systemic Dosing of siRNA

Arrowhead subsidiary, Calando Pharmaceuticals publishes study on targeted systemic delivery of of siRNA

PASADENA, CA | Posted on March 20th, 2007

Arrowhead Research Corporation
(NASDAQ: ARWR) announced today that majority-owned subsidiary Calando
Pharmaceuticals has published results in the Proceedings of the
National Academy of Sciences (PNAS) of the first non-human primate
study to use multiple, systemic dosing with Calando's lead siRNA
therapeutic candidate.

Calando is using its proprietary technologies in targeted polymeric
delivery systems and siRNA design to create new, targeted siRNA
therapeutics. Its lead anti-cancer therapeutic candidate contains a
linear cyclodextrin polymer, the siRNA, and a targeting agent. The
formulation self assembles into nanoparticles that protect the siRNA
from nuclease degradation in serum. One important result of the study
was the lack of a significant immune response to the siRNA,
demonstrating that the formulation is well tolerated at doses much
higher than those previously shown to have anti-cancer effects.
Calando is expecting to enter clinical trials with this formulation
later this year.

Further information about Calando and the study can be found at
http://www.calandopharma.com .

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About Arrowhead Research Corporation
Arrowhead Research Corporation ( http://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 four subsidiaries commercializing nanotech
products and applications, including anti-cancer drugs, RNAi
therapeutics, carbon-based electronics and compound semiconductor
materials.

About Calando Pharmaceuticals Inc.

Calando Pharmaceuticals Inc. ( http://www.calandopharma.com )
(www.calandopharma.com), a majority owned subsidiary of Arrowhead
Research Corporation (NASDAQ: ARWR), is using its proprietary
technologies in targeted polymeric delivery systems and siRNA design
to design and create new, targeted siRNA therapeutics. The company is
pursuing this goal through its internal research and development and
also through collaborations and partnerships with pharmaceutical and
biotechnology companies.

Calando Technology

Calando's cyclodextrin-containing polymers form the foundation for
its two-part siRNA delivery system. The first component is a linear,
cyclodextrin-containing polycation that, when mixed with small
interfering RNA (siRNA), binds to the anionic "backbone" of the
siRNA. The polymer and siRNA self-assemble into nanoparticles of
approximately 50-80 nm diameter that fully protect the siRNA from
nuclease degradation in serum. The siRNA delivery system has been
designed to allow for intravenous injection. Upon delivery to the
target cell, the targeting ligand binds to membrane receptors on the
cell surface and the RNA-containing nanoparticle is taken into the
cell by endocytosis. There, chemistry built into the polymer
functions to unpackage the siRNA from the delivery vehicle. In
addition to targeting tumors, the targeting of liver cells has also
been accomplished in vivo.

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Act of 1995

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