Lead antibody targeting novel epitope of CD44 found in breast, colon and prostate cancers

TORONTO, Canada | October 23, 2007|  ARIUS Research Inc., (TSX: ARI), a biotechnology company discovering and developing the next wave of antibody therapeutics, today announced that the lead drug candidate from its CD44 Cancer Stem Cell program has successfully completed its first toxicology study and has shown good efficacy in animal models. ARIUS’ program targets a novel epitope of CD44 that has been found in a number of cancer indications including breast, colon, and prostate cancers. Two humanized versions of the CD44 targeting antibody have been generated in preparation for the initiation of human clinical trials in 2008.

"To be effective against cancer, a treatment must eliminate the cancer stem cells at the heart of the disease that are driving tumor growth and seeding new tumors," said Dr. David Young, President and CEO. "Our CD44 targeting antibody is one of the most advanced drug candidates to target cancer stem cells. CD44 is considered an especially attractive target for anti-tumor drug discovery and development because it has been identified as a cancer stem cell marker in breast, prostate and colon cancers.

Having now successfully completed our initial CD44 toxicology study, we look forward to moving our CD44 antibody toward human clinical trials in 2008."

Toxicology Presentation

ARIUS has demonstrated that its antibody targets a novel epitope of CD44 that is present on the majority of human tumors. A dose-ranging pilot toxicology study in non-human primate models demonstrated no dose-limiting toxic effects at doses up to 95 mg/kg. Effects observed in healthy animals were minor and transient.

Efficacy Presentation

ARIUS’ CD44 targeting antibody has demonstrated significant tumor growth inhibitory activity in in vivo animal models of breast, prostate, liver, and AML cancers. In breast cancer models, the antibody demonstrated tumor regression with increased survival at all doses. Two humanized versions of the
antibody have been generated and their affinity is comparable to that of the chimeric and murine antibodies. The results of this study have also demonstrated the potential for the antibody to target the cancer stem cell antigen in breast cancer. The potency of the two humanized antibodies on tumor
growth inhibition has been demonstrated in established tumor models in preparation for human clinical trials in 2008.

About ARIUS

ARIUS is a biotechnology company discovering and developing the next wave of antibody therapeutics. Established in 1999, ARIUS has built a proprietary technology platform, FunctionFIRST(TM), that rapidly identifies and selects antibodies based on their functional ability to affect disease. This antibody generation engine has enabled ARIUS to assemble a portfolio of more than 400 antibody candidates. In addition to the antibodies it is developing in-house, ARIUS has ongoing partnerships with key biotechnology and drug development companies. ARIUS is listed on the TSX under the symbol "ARI". For further information, visit www.ariusresearch.com

SOURCE: ARIUS Research Inc.