Adherex Technologies Issued Patent for Method of Improving Drug Delivery to Tumors.

RESEARCH TRIANGLE PARK, N.C. -- Adherex Technologies Inc. (TSX:AHX), a biopharmaceutical company with a broad portfolio of oncology products under development, today announced that it has been issued U.S. Patent No. 6,797,807, entitled "Compounds and Methods for Cancer Therapy." The patent covers the use of the Company's proprietary cancer therapeutic agents to improve drug delivery to tumors by preventing a cell adhesion protein, known as occludin, from forming cellular barriers within tumors. The patented method may also improve the ability of immune cells to infiltrate tumors.

"Cancerous tumors have evolved sophisticated mechanisms for fighting off attempts to kill them," said Orest Blaschuk, Ph.D., Chief Scientist and Co-Founder of Adherex. "Some tumors are able to form barriers that prevent foreign materials, such as drugs or antibodies, from getting inside them, thus reducing the effectiveness of those therapeutics. These barriers form in some tumors due to a protein, known as occludin, which acts as "glue" that tightly binds tumor cells together. This patent covers the use of our technologies to knock down those occludin-based barriers, enabling drugs and the body's immune cells to more easily get inside tumors and attack them."

"Adherex is dedicated to the discovery and development of novel cancer therapeutics. The use of vascular targeting as a new strategy in cancer treatment holds major potential to improve cancer treatment. One of Adherex's greatest assets is our intellectual property related to cell adhesion molecules, including cadherins, occludin and other adhesion molecules. Adherex has an expansive patent portfolio covering methods to break down tumor barriers, which we hope to transform into important new options for treating patients," said William P. Peters, MD, PhD, Chairman and CEO of Adherex. "I believe that the most successful cancer treatments of the future will target tumors in unique ways without significantly affecting healthy tissues. We are developing drug candidates, such as Exherin(TM), that specifically target cell adhesion molecules. Such targeted therapeutics hold the promise of being more effective with fewer side effects. That is our focus and our challenge."

About Adherex Technologies

Adherex Technologies Inc. is a biopharmaceutical company dedicated to the discovery and development of novel cancer therapeutics. We aim to be a leader in developing innovative treatments that address important unmet medical needs in cancer. We currently have four products in the clinical stage of development including Exherin(TM) and sodium thiosulfate (STS). Exherin(TM), our lead biotechnology compound, is an angiolytic that selectively targets established blood vessels that feed solid tumors. STS, a drug from our specialty pharmaceuticals pipeline, protects against the disabling hearing loss that can often result from treatment with platinum-based chemotherapy drugs. With a diversified portfolio of unique preclinical and clinical-stage cancer compounds and a management team with expertise in identifying, developing and commercializing novel cancer therapeutics, Adherex is emerging as a pioneering oncology company. For more information, please visit Adherex' website at www.adherex.com.

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Certain information contained in this news release is forward-looking and is subject to unknown risks and uncertainties. The actual results, performance or achievements of the Company may differ materially from the results, performance or achievements of the Company expressed or implied by such forward-looking statements.